LWN.net Weekly Edition for April 2, 2009

GCC debates project governance

When we last looked in on GCC, the 4.4 release branch was held up by licensing issues, specifically the exemption that would allow GCC plugins. Since that time, things have progressed—there is now a 4.4 release branch—but the license issue has not yet been completely resolved, though a new revision is available. But, since the license change is not needed for the 4.4 release, some GCC hackers are unhappy about the manner in which the release was held up. It has led to questions about the roles of the Free Software Foundation (FSF) and the GCC steering committee (SC) have in controlling GCC development.

Holding up a release for licensing concerns is seen by many as a reasonable request that the FSF might make. That organization is very concerned about licenses, in general, and they certainly think it is important to get the license right before releasing any code under the license. It is the concerns expressed by GCC developers about the wording of the runtime library exception that led to the license review. But Richard Stallman, acting for the FSF, did not ask that the release be delayed—at least directly—he asked that no release branch be created. The net effect on the release process is the same (i.e. no release), but the impact on development of new features destined for GCC 4.5 is a large part of what irked the GCC developers.

The other piece of the puzzle is that the issue is essentially moot: there is no plugin API in GCC 4.4 that would require the runtime library exemption changes. Stallman is adamant that proprietary GCC plugins be outlawed before such an API gets added. But, since the API isn't present (yet), the license changes aren't needed yet either. So, while it makes sense to take whatever time is required to get the license right, many seem very puzzled as to why that would need to hold up the release and new development.

There has never been a clear explanation of why the release branch needed to be delayed, at least publicly. Either Stallman relented—perhaps due to completing the license rewording—or the SC eventually decided to override his request because the release branch was created on March 27. But there was clear discontent in the ranks that the SC could, evidently, be pushed around so easily by the FSF. This led to questions about the role of the SC, how much control over "technical" decisions the FSF has, and, in general, how the project is governed. As Daniel Berlin put it: "Where is the pushback by the SC onto the FSF?"

Berlin's complaint was that it has taken the FSF too long to resolve the issue, to the point where it is now (and has been for a bit) seriously impacting GCC development. Because the license change is not required for this release, there is no good reason to delay it. Ian Taylor was fairly blunt:

In response to Berlin's criticism of their response, SC member David Edelsohn noted that there were things going on behind the scenes:

But a lack of communication from the SC to the greater GCC community is part of the problem, according to Berlin:

The discussion then turned to the role that the FSF plays in GCC development. SC member Joe Buck points out that the FSF holds the cards: "The problem in this instance is that the SC has little power; it's the FSF that's holding things up and I don't know more than you do." But that doesn't sit well with some. Steven Bosscher asks:

Others believe that the FSF should be in complete control. Richard Kenner outlines how he sees the relationship:

Berlin would like to see the governance structure for GCC more clearly spelled out. The SC web page seems to indicate that its role is to prevent the project from being controlled by any party. But whether the SC is supposed to prevent the FSF from controlling its own project was disputed. Ultimately, the developers do have some power as Buck states: "There are checks on FSF control in the sense that the project can be forked and developers can leave."

That kind of talk inevitably leads some to mention the egcs/GCC split, and subsequent join, as an example of the power that the development community has. No one has said they are seriously considering a fork, but the GPL certainly allows such things if the FSF's hand gets too heavy. Jeff Law doesn't see it coming to that:

Clearly some developers are chafing under what they see as unnecessary interference in technical issues from Stallman. But as Buck points out, Stallman does not dictate technical details to GCC. Various decisions (bugtracker, version control, etc.) have gone against his express wishes. In addition, contrary to Stallman's aversion to C++, Taylor has used that language for the gold linker, and currently has a branch that implements some of GCC in C++. He sees things this way:

This discussion will hopefully lead to a clearer picture of the governing structure of GCC. With luck, it may also make Stallman and the FSF more cognizant of the perception that they are meddling in technical issues to the detriment of their relationship with at least some in the community. No one in the rather long thread could come up with any sensible reason that the release branch should have been held up. At best, that means that Stallman didn't communicate the why, which leads many to a sense that he is being rather arbitrary.

In the meantime, though, GCC is preparing for the 4.4 release. Release manager Mark Mitchell created the release branch, Bosscher is rounding up folks to update the 4.4 changes page, and work is proceeding towards a release. That also allows the changes for 4.5 to be added to the trunk, which puts that release back on track.

With GCC 4.5 there will likely be a new plugin API for which the license change is needed. On April 1, Edelsohn announced that the revised runtime library exception had been released. It explicitly allows for Java byte code to be used as input into GCC, making a "compilation process" using that input eligible for the runtime library exception. One of the other concerns, regarding independent modules, will be addressed in the FAQ, though it has not been at the time of this writing.

Assuming the new exception passes muster on the gcc-devel list, and no problems are found that would require adjustments, it will presumably end up in the 4.4 release. While that should conclude this particular issue, the overarching governance questions will remain.

Comments (11 posted)

New Theora encoder makes its first public release

Xiph.org achieved a milestone last week, unveiling the first public release of its new encoder for Theora video. The new encoder is codenamed Thusnelda to distinguish it from previous work, and makes several big improvements, including fixes to constant bitrate and variable bitrate encoding.

Theora is derived from a video codec called VP3 created by On2 Technologies. On2 donated the code to VP3 and to the public under an open source license in 2001, and agreed to help Xiph.org develop Theora as its successor. The specification for the Theora codec's format was finalized in 2004, but the reference encoder itself — the actual binary that converts a video file into Theora format — only reached 1.0 in November of 2008. Work on Thusnelda began shortly thereafter, spearheaded by Xiph.org's Christopher Montgomery, but was bolstered by a grant from Mozilla and the Wikimedia Foundation that allowed lead Theora developer Tim Terriberry to focus on improving the encoder to coincide with the built-in Theora support slated for Firefox 3.5.

What's new

The Thusnelda encoder is denoted 1.1 alpha, and is available for download from Xiph.org in several formats: source code for the libtheora library, binaries of the ffmpeg2theora command-line conversion utility, and even a Mac OS X Quicktime component.

According to Xiph.org's Ralph Giles, the most noticeable improvement in 1.1 is proper rate control, particularly for fixed bit rate encoding, where the user specifies either the number of bits per second desired in the output (a common use case for streaming applications), or the desired file size. "The 1.0 encoder relies a lot on heuristics, instead of trying to optimize directly the trade-off between quality of the coded images and the number of bits used to represent them," he said, "More significantly, the fixed bitrate mode in the 1.0 reference encoder didn't really work; it just guessed how to meet its target and often missed the requested bitrate, sometimes by quite a bit, which was a problem for streaming and fixed-size encodes."

But Montgomery's work — supported for a year by his employer Red Hat — also included extensive refactoring of the code, which should result in improvements today and allow for easier changes moving forward. "The older encoder was structured as a bunch of nearly independent passes," Giles said, "[it] made something like 8 passes over each frame. This made some forms of decision making hard, i.e. if an earlier decision caused you problems (higher bitrate) in a later stage you were out of luck. The new encoder collapses most of the passes."

The restructuring also allows Thusnelda to take advantage of features in the Theora specification that had never been implemented before, such as "4MV" macroblocks, a motion compensation scheme that adaptively chooses whether to encode motion information for an entire segment of the picture, for a sub-segment, or for none of the segment. "Theora always breaks each image up into square blocks," Giles explained, "one of those blocks then can be split into four motion vectors, or use an average, and if any of those four don't need to be coded, the alpha encoder can skip coding a corresponding motion vector. Making a change like that was too difficult with the 1.0 codebase."

Measuring success

Naturally, real-world performance and not a feature list is the primary means of assessing an encoder. Theora has been the object of criticism in years past, especially when compared against proprietary offerings such as H.264. Reader comments on news stories at Slashdot often dismissed Theora as a poor alternative, producing larger files than the competition for the same subjective quality.

Codec testers are always at the mercy of the encoder, however, and as noted above Theora's 1.0-series encoder had significant flaws, especially with respect to constant bitrate encoding. In the oft-cited doom9.org 2005 codec shootout, the Theora encoder performed poorly by failing to meet the target file size due to poor rate control; the very feature targeted in the 1.1 branch. Similarly, Eugenia Loli-Queru's 2007 Theora versus H.264 test for OSNews repeatedly cited problems with the encoder that made direct comparison close to impossible.

Both tests pre-date the 2008 release of the final 1.0 encoder, much less the 1.1 alpha. Shortly after the Thusnelda alpha, Jan Schmidt posted the results of his personal tests on his blog, indicating a 20% reduction in file size and 14% reduction in encoding time over the 1.0 encoder. Those are significant numbers, even without accounting for better rate control and other encoding parameter improvements. As commenters to the blog pointed out, Schmidt's test was not scientific, particularly as it involved re-encoding an H.264 file rather than a lossless original, and showed example still frames rather than video results.

Video quality is ultimately a subjective, human-centric measure. Although there are attempts to quantify video encoding quality, such as peak signal-to-noise ratio (PSNR) and structural similarity index (SSIM), they rarely replace subjective evaluations of quality. Xiph's Gregory Maxwell said that Thusnelda improves on Theora's PSNR, but that it was a mistake to assume that that equated to a subjective improvement for any particular use case.

Terriberry concurred, noting that none of the simple objective metrics take any kind of temporal effects into account, and they are still less trustworthy than the processing done in the brain. "Like most things, it's a matter of knowing what the limitations of your tools are. PSNR and SSIM are useful for monitoring day-to-day changes in the code to identify regressions and optimize parameters. But for evaluating fundamentally different approaches, there's currently no substitute for using real humans."

Theora took hits from critics on subjective quality in the 2005 and 2007 tests, too, points which Montgomery responded to in 2007 with a page on his personal Web site. Although some subjective quality issues like discernible blockiness are not the result of problems with the 1.0 encoder, he argued, many of the most visible problems are, and he urged readers to watch the progress made in the 1.1 series.

What's next

There are several improvements still to come before 1.1 is declared final, according to the Theora team. Giles said the next major feature will be per-block quantizers, the functions that simplify a block of input data into smaller values for output. "[Theora precursor] VP3 used a fixed set of quantizers, and the "quality" knob was the only way you could change things. When VP3 became Theora, back 2004, we added support for varying those quantizers both per video, and per frame type. The 1.0 encoder was able to support alternate quantizer matrices, because you just switch them out, but there were some tuning issues."

"1.1alpha1 is still using the same set, but we expect that the change soon," Giles said. The newly-restructured codebase makes it easy to vary the quantizer used, not just on a per-file or per-frame basis, but block-by-block. Terriberry added that the new code will support 4:2:2 and 4:4:4 pixel formats, which will allow higher color quality, and the ability to use different quantization matrices for different color channels and frames.

Giles and Terriberry agreed that 1.1 final will be significantly better than even the current alpha release once all of the changes are incorporated. Terriberry noted that many of the remaining improvements are "minor things" but that added together they will be substantial. "And that's not even mentioning things like speed optimizations, which also have real practical benefits."

"There are other things still on the docket as well — we're not done yet!" added Montgomery, "However, we're finally to the point of putting together a release solidly better than 1.0 in every way, along with a much higher future ceiling."

Between now and then, the team is soliciting user input from real-world encoding tests. "We put it out to show what we've been up to, and to make it easier to give it a try," said Giles. "We're interested in samples where it really does poorly, especially relative to 1.0, compatibility testing with current decoders, and general build and integration issues which of course can only be found through people trying your software in their own environments." He encouraged users to submit concrete issues through the bug tracker, but to share other experiences through the project mailing list, or simply to blog about them for all to read.

Web video is poised to start changing dramatically once Firefox 3.5 ships with a built-in Theora decoder underlying the HTML5 video element. That makes it all the more important to get the Theora encoder right. Xiph.org does not have the full-time staff or resources of larger activist groups like the Free Software Foundation or Creative Commons, it has only software developers. Consequently, without the support of Red Hat, Mozilla, and the Wikimedia Foundation, it might not have been able to get up to speed. It remains to be seen whether the final build of Thusnelda will beat Firefox 3.5 to release, but the progress made already is encouraging.

Comments (13 posted)

OSBC: Life at the edge of the GPL

The Open Source Business Conference, held at San Francisco's Palace Hotel, draws a lot of lawyers, from both corporate legal departments and law firms. Continuing Legal Education (CLE) credit is available. Jeff Norman, a partner at the law firm of Kirkland & Ellis, delivered a talk on "Shims and Shams: Firewalling Proprietary Code in a Copyleft Context." This talk gives some insights into the current thinking on how difficult it can be to create a combined software product using both copyleft and proprietary code.

Most clients who want to combine GPL and proprietary code, Norman said, do not have an open source business model in mind. But the idea of creating a mixed GPL/proprietary software product is difficult and expensive. Step one for the lawyer is to explore the reasons behind the idea. The question is: "Why do you want to do something unusual instead of complying with open source disclosure requirements?" Only if the client says, "We can't open source this," does Norman recommend what he calls "shimming," which he defines as "programing practices and architectures that reduce the risk that independently created proprietary code might be deemed a derivative work based upon some other code that is intended to operate with such proprietary code." Shimming includes both procedural shims, which are development practices, and substantive shims, which are design decisions.

The GPL's reciprocity requirements rely not on any technical criterion, but on the legal definition of a "derivative work." The definition is actually consistent across countries. Norman surveyed the law in US, Europe, and Asia, and found "little substantial difference." While the definition is consistent, it's also broad, often surprisingly broad. Case law shows that derivative works can come into existence easily, whenever pre-existing work is either incorporated into new work or modified.

Two cases show the wide reach of the derivative work concept. A.R.T Company sold products based on unmodified postcards, and in one case was found to be creating a derivative work. (Another case found that A.R.T.'s product consisting of a postcard mounted on a tile was not infringing, creating a conflict between two U.S. circuit courts.) In another case, Midway Manufacturing Co. v. Artic International, Inc., the court found that selling a hardware speed-up kit for an existing arcade game was creating a derivative work of the game software, even though the defendant did not copy or modify the original game software. Courts use the test of "access and substantial similarity." If the alleged infringer had access to the copyrighted work, and even parts of the alleged derivative work are substantially similar, then, according to the test, it's a derivative work. Applying the idea to software, "proprietary code may incorporate non-proprietary code in non-obvious ways," Norman said.

"There are built in to most computer languages directives that cause code to be combined," he said. The C preprocessor's #include directive is one example. "I've seen hundreds of thousands of lines of code incorporated with one include." In one example, a proprietary program used a widget class's API, and the widget class, using a header file, incorporated code from a system library. "This whole thing becomes a derivative work," he said.

Distribution or not?

If a combination of GPL and proprietary code is only for in-house use, some clients decide simply not to redistribute it. The GPL's reciprocity requirements apply only in distribution. However, distribution could happen in a lot of ways. Does depositing source code in escrow count as distribution? How about an acquisition that's structured as a sale of assets from one company to another? "Relying on no distribution is very dangerous. There are a lot of situations where distribution can happen but you wouldn't think of it as distribution," Norman said.

The other approach is what Norman recommends. "Don't create a derivative work and then you won't have a problem." He said that some open source advocates say, "You're violating the spirit or the purpose of the GPL." But in the long run, allowing a license to reach out too far could enable proprietary vendors to apply unwanted terms to open source code. "If the end user is not creating a derivative work, not only are the license terms not being triggered but you don't want them to be triggered,"

Fallacies

In the years that developers have been using and discussing the GPL, some have developed a false sense of security about when they're creating a derivative work. Just using an API may or may not create a derivative work. The purely functional aspects of a function call are not copyrightable. However, Norman says, even minor non-functional aspects of an API, such as the sequence of fields in a structure, are probably copyrightable. And just using an API can result in bringing thousands of lines of code into your application. Another fallacy is the often-heard, "We can avoid any problems if we use dynamic rather than static links," However, dynamic linking by itself does not automatically avoid creating a derivative work.

Some US circuits ignore extremely small copying under the so-called "de minimis" exception. However, Norman said, "it would almost never cover code," There's no sure test for what is or isn't de minimis copying, and one module or section of a program could be found to be a derivative work. "Even if the whole project is not substantially similar, one module may be substantially similar," he added.

The clean room

With the broad standards of what is a derivative work, combined with the ways that software can mingle at build time, "derivative works practically create themselves," Norman said. In order for a combined product not to be a derivative work, developers need to take specialized and expensive measures. Avoiding creating a derivative work is not something to do in the ordinary course of business. Shimming requires the same clean-room techniques that software companies use to protect themselves when doing reverse engineering. Building a combined product cleanly "really has to be worth it," Norman said. "If you have someone who has never done a clean room before you're going to spend time getting them up to speed." Besides the development costs, there's some publicity cost. "In any shimming scenario you may get some negative PR," he said.

The wrong way to do shimming is simply to build a wrapper, implementing essentially the same interface as the GPL software, then communicate with the wrapper. It doesn't work because the wrapper becomes a derivative work, then the code that talks to the wrapper does too. In practice, two development teams need to work side by side, but not in direct communication with each other. One team handles GPL code, the other handles the proprietary code, and the two communicate only through the legal department, which acts as filter.

They have to be kept separate, Norman says, because, "Programmers like to borrow just like lawyers. How often do you borrow from somebody else's brief?" The filtering has to block any knowledge about creative expression from making its way across the barrier. Since anyone could have seen the GPL code, "We have a set of programmers who verify under affidavit that they've never looked at this code before." The clean room developers' access to the Internet has to be monitored, or better yet, blocked. "It's a fairly cumbersome technique, but most software companies have done some kind of clean room before," Norman said.

NDISwrapper is an example of another safe approach, Norman said. A network device driver originally written and compiled for Microsoft Windows cannot be a derivative work of Linux. NDISwrapper itself is GPL-licensed, and probably a derivative work of Linux (it's very difficult to make a kernel module that isn't). The API used in the Windows driver clearly has nothing to do with the copyleft API.

Another approach is to split the GPL code into a server process and put the proprietary code in the client. However, this is unlikely to work if the server and client are distributed together on the same CD, relying on what the GPL calls "mere aggregation." Any "intimate communication" between the server and client could also create a derivative work, Norman said. The last approach is to time-shift the creation of a derivative work to the end user. An example is the NVIDIA proprietary device drivers for Linux, which the company distributes separately from the kernel. This only works for technical or hobbyist end users, not for an integrated product. There's also a potential patent problem: distributing two pieces that, when combined, infringe a patent constitutes contributory infringement, Norman said later.

A problem shimming scenario is using it to attempt to undo a previous decision to combine software. It could be "admitting that what you did was problematic." If possible, try to buy a exception from the copyright holder instead, Norman said. Shimming is possible and might even be necessary, as in the case of third-party code that can't be relicensed. But the lesson is that companies will save time, use fewer developers, make a simpler product, and avoid legal bills just sticking with the copyleft.

Comments (36 posted)

Page editor: Jonathan Corbet

Security

Integrity management using Intel TXT

Being able to verify that the code running on a system is the "correct" code is an important feature for some environments. The Linux integrity management architecture (IMA) patches—recently merged for 2.6.30—look at the integrity of processes as they are started by the kernel. But that requires running on a "good" kernel. So a patch, recently put out for comments on linux-kernel, proposes a lower-level mechanism which uses Intel's Trusted Execution Technology (TXT) to verify the integrity of the kernel itself.

Whereas the IMA lives completely within the Linux kernel, but uses Trusted Platform Module (TPM) hardware to check and enforce the integrity of code that is executed, the TXT-based integrity system interposes a virtual machine monitor (VMM or hypervisor) between the hardware and the kernel. This hypervisor, called Trusted Boot or tboot interacts with the TXT hardware, which is contained in various recent Intel chipsets, to verify the integrity of the kernel before launching it.

The TXT hardware can itself verify the integrity of many of the firmware components (things like BIOS and option ROMs) that must be assumed when using IMA. In their introductory post, Joseph Cihula and Shane Wang of Intel describe the advantages of a TXT-based integrity system as follows:

It is interesting that they mention system management mode (SMM) as that has recently been the target of some research on undetectable rootkits. The kind of malware described in the research could subvert even TXT-based integrity systems.

In a followup post, Cihula and Wang describe in some detail how TXT, tboot, and the kernel cooperate to make it all work. Tboot is loaded by the bootloader—typically grub—as the "kernel". The grub.conf file lists the Linux kernel and Intel-supplied binary-only "authenticated code module" as "modules" that get loaded as well. For those who wish it, tboot also supports launching the Xen hypervisor, instead of the Linux kernel, as the guest. Tboot then does all of the setup necessary to determine if the TXT environment is present and configured correctly, if not, it just launches the kernel as usual. But if it finds a proper TXT environment, it initiates the integrity checking and verifies the hardware environment.

At that point, user-defined policies are consulted to determine the how to verify the integrity of the kernel and initial ramdisk (initrd) and what to do if verification fails. Tboot creates a shared page of memory and populates it with some data about itself for the kernel to use. The physical address of the shared page is passed to the kernel as a boot parameter. The kernel then maps that page as part of the boot process.

The shared page is also used by the kernel to communicate its intent to move to one of the sleep states of the processor. Instead of directly sleeping, it informs tboot of all of the relevant ACPI data via the shared page and jumps into tboot via a vector listed in the page. When going into the standby (suspend to RAM or S3) sleep, additional steps are taken to ensure the memory integrity across the S3 boundary. This is done by calculating a hash value over critical memory regions (kernel code and data as well as the S3 resume code) and signing it using the TPM. The user-supplied tboot policies determine what actions to take if the RAM verification fails upon coming out of S3.

The patch itself is relatively small and comments on it nearly non-existent. While it provides a potentially interesting protection against various attack scenarios, it also adds a layer underneath the kernel. In addition, there are some binary components to tboot that may raise some eyebrows. It will be interesting to see what kind of reception it gets, once folks start looking at it.

Comments (1 posted)

Brief items

An update on the Fedora August 2008 intrusion

The Fedora project has sent out an update on last August's intrusion; there is quite a bit more information here now. "The compromise was not the result of a software vulnerability, and as we have previously stated, our investigation has revealed no such vulnerabilities. Instead, the intruder took a copy of a SSH private key which was not secured with a passphrase from a system outside the Fedora infrastructure. The intruder then used that key, which belonged to a Fedora administrator, to access Fedora systems."

Full Story (comments: 27)

Vast Spy System Loots Computers in 103 Countries (New York Times)

The New York Times broke the story of "GhostNet", a globe-spanning infiltration of computers, most of which are controlled by various governments. In investigating malware at the offices of the Dalai Lama, security researchers found a much larger operation. "Their sleuthing opened a window into a broader operation that, in less than two years, has infiltrated at least 1,295 computers in 103 countries, including many belonging to embassies, foreign ministries and other government offices, as well as the Dalai Lama’s Tibetan exile centers in India, Brussels, London and New York. [...] The researchers, who have a record of detecting computer espionage, said they believed that in addition to the spying on the Dalai Lama, the system, which they called GhostNet, was focused on the governments of South Asian and Southeast Asian countries."

Comments (7 posted)

New vulnerabilities

acroread: multiple vulnerabilities

Package(s):	acroread	CVE #(s):	CVE-2009-0193 CVE-2009-0658 CVE-2009-0927 CVE-2009-0928 CVE-2009-1061 CVE-2009-1062
Created:	March 27, 2009	Updated:	April 21, 2009
Description:	From the SUSE advisory: Multiple flaws in the JBIG2 decoder and the JavaScript engine of the Adobe Reader allowed attackers to crash acroread or even execute arbitrary code by tricking users into opening specially crafted PDF files.
Alerts:	SuSE SUSE-SR:2009:009 2009-04-21 SuSE SUSE-SA:2009:014 2009-03-27 Gentoo 200904-17 2009-04-18

Comments (none posted)

auth2db: SQL injection

Package(s):	auth2db	CVE #(s):
Created:	March 30, 2009	Updated:	April 1, 2009
Description:	From the Debian advisory: It was discovered that auth2db, an IDS logger, log viewer and alert generator, is prone to an SQL injection vulnerability, when used with multibyte character encodings.
Alerts:	Debian DSA-1757-1 2009-03-30

Comments (none posted)

firefox: remote code execution

Package(s):	epiphany	CVE #(s):	CVE-2009-1169 CVE-2009-1044
Created:	March 28, 2009	Updated:	April 20, 2009
Description:	Versions of the firefox browser through 3.0.7 suffer from two remote code execution vulnerabilities; one of them was used to win the 2009 CanSecWest Pwn2Own contest and has active exploits circulating. The 3.0.8 release closes the holes.
Alerts:	SuSE SUSE-SA:2009:023 2009-04-20 CentOS CESA-2009:0397 2009-04-09 Mandriva MDVSA-2009:084 2009-04-01 Fedora FEDORA-2009-3161 2009-03-30 Fedora FEDORA-2009-3101 2009-03-30 Fedora FEDORA-2009-3100 2009-03-28 Fedora FEDORA-2009-3100 2009-03-28 Fedora FEDORA-2009-3100 2009-03-28 Fedora FEDORA-2009-3100 2009-03-28 Fedora FEDORA-2009-3100 2009-03-28 Fedora FEDORA-2009-3100 2009-03-28 Fedora FEDORA-2009-3100 2009-03-28 Fedora FEDORA-2009-3100 2009-03-28 Fedora FEDORA-2009-3100 2009-03-28 Fedora FEDORA-2009-3100 2009-03-28 Fedora FEDORA-2009-3100 2009-03-28 Fedora FEDORA-2009-3100 2009-03-28 Fedora FEDORA-2009-3100 2009-03-28 Fedora FEDORA-2009-3100 2009-03-28 Fedora FEDORA-2009-3100 2009-03-28 Fedora FEDORA-2009-3100 2009-03-28 Fedora FEDORA-2009-3100 2009-03-28 Fedora FEDORA-2009-3100 2009-03-28 Fedora FEDORA-2009-3100 2009-03-28 Debian DSA-1756-1 2009-03-29 CentOS CESA-2009:0398 2009-03-28 Fedora FEDORA-2009-3099 2009-03-28 Fedora FEDORA-2009-3099 2009-03-28 Fedora FEDORA-2009-3099 2009-03-28 Fedora FEDORA-2009-3099 2009-03-28 Fedora FEDORA-2009-3099 2009-03-28 Fedora FEDORA-2009-3099 2009-03-28 Fedora FEDORA-2009-3099 2009-03-28 Ubuntu USN-745-1 2009-03-28 Slackware SSA:2009-086-01 2009-03-28 Red Hat RHSA-2009:0398-01 2009-03-27 Red Hat RHSA-2009:0397-01 2009-03-27 Fedora FEDORA-2009-3099 2009-03-28 Fedora FEDORA-2009-3099 2009-03-28 Fedora FEDORA-2009-3099 2009-03-28 Fedora FEDORA-2009-3099 2009-03-28 Fedora FEDORA-2009-3099 2009-03-28 Fedora FEDORA-2009-3099 2009-03-28 Fedora FEDORA-2009-3099 2009-03-28 Fedora FEDORA-2009-3099 2009-03-28 Fedora FEDORA-2009-3099 2009-03-28 Fedora FEDORA-2009-3099 2009-03-28 Fedora FEDORA-2009-3099 2009-03-28 SuSE SUSE-SA:2009:022 2009-04-20 Gentoo 201301-01 2013-01-07

Comments (none posted)

java-1.6.0-sun: multiple vulnerabilities

Package(s):	java-1.6.0-sun	CVE #(s):	CVE-2006-2426 CVE-2009-1093 CVE-2009-1094 CVE-2009-1095 CVE-2009-1096 CVE-2009-1097 CVE-2009-1098 CVE-2009-1099 CVE-2009-1100 CVE-2009-1101 CVE-2009-1102 CVE-2009-1103 CVE-2009-1104 CVE-2009-1105 CVE-2009-1106 CVE-2009-1107
Created:	March 26, 2009	Updated:	November 18, 2009
Description:	Java 1.6.0 has a long list of vulnerabilities. From the Red Hat alert: CVE-2006-2426 Untrusted applet causes DoS by filling up disk space CVE-2009-1101 OpenJDK JAX-WS service endpoint remote Denial-of-Service CVE-2009-1093 OpenJDK remote LDAP Denial-Of-Service CVE-2009-1094 OpenJDK LDAP client remote code execution CVE-2009-1095 CVE-2009-1096 OpenJDK Pack200 Buffer overflow vulnerability CVE-2009-1102 OpenJDK code generation vulnerability CVE-2009-1097 OpenJDK PNG processing buffer overflow vulnerability CVE-2009-1098 OpenJDK GIF processing buffer overflow vulnerability CVE-2009-1099 OpenJDK: Type1 font processing buffer overflow vulnerability CVE-2009-1100 OpenJDK: DoS (disk consumption) via handling of temporary font files CVE-2009-1103 OpenJDK: Files disclosure, arbitrary code execution via "deserializing applets" CVE-2009-1104 OpenJDK: Intended access restrictions bypass via LiveConnect CVE-2009-1105 OpenJDK: Possibility of trusted applet run in older, vulnerable version of JRE CVE-2009-1106 OpenJDK: Improper parsing of crossdomain.xml files (intended access restriction bypass) CVE-2009-1107 OpenJDK: Signed applet remote misuse possibility
Alerts:	Red Hat RHSA-2009:1198-02 2009-08-06 Mandriva MDVSA-2009:162 2009-07-28 SuSE SUSE-SA:2009:036 2009-07-02 Mandriva MDVSA-2009:137 2009-06-20 Gentoo 200911-02 2009-11-17 SuSE SUSE-SR:2009:011 2009-06-09 SuSE SUSE-SA:2009:029 2009-05-25 Red Hat RHSA-2009:1038-01 2009-05-18 Debian DSA-1769-1 2009-04-11 CentOS CESA-2009:0377 2009-04-08 Red Hat RHSA-2009:0377-01 2009-04-07 SuSE SUSE-SA:2009:016 2009-04-03 Ubuntu USN-748-1 2009-03-26 Red Hat RHSA-2009:0394-01 2009-03-26 Red Hat RHSA-2009:0392-01 2009-03-26

Comments (none posted)

kernel: denial of service

Package(s):	kernel	CVE #(s):	CVE-2009-0778
Created:	April 1, 2009	Updated:	February 3, 2010
Description:	From the Red Hat advisory: Memory leaks were found on some error paths in the icmp_send() function in the Linux kernel. This could, potentially, cause the network connectivity to cease. (CVE-2009-0778, Important)
Alerts:	Red Hat RHSA-2010:0079-01 2010-02-02 CentOS CESA-2009:0326 2009-04-01 Red Hat RHSA-2009:0326-01 2009-04-01

Comments (none posted)

krb5: denial of service

Package(s):	krb5	CVE #(s):	CVE-2009-0844 CVE-2009-0845 CVE-2009-0846 CVE-2009-0847
Created:	March 30, 2009	Updated:	January 14, 2010
Description:	From the Mandriva advisory: The spnego_gss_accept_sec_context function in lib/gssapi/spnego/spnego_mech.c in MIT Kerberos 5 (aka krb5) 1.6.3, when SPNEGO is used, allows remote attackers to cause a denial of service (NULL pointer dereference and application crash) via invalid ContextFlags data in the reqFlags field in a negTokenInit token (CVE-2009-0845). From the Red Hat advisory: An input validation flaw was found in the ASN.1 (Abstract Syntax Notation One) decoder used by MIT Kerberos. A remote attacker could use this flaw to crash a network service using the MIT Kerberos library, such as kadmind or krb5kdc, by causing it to dereference or free an uninitialized pointer. (CVE-2009-0846) Multiple input validation flaws were found in the MIT Kerberos GSS-API library's implementation of the SPNEGO mechanism. A remote attacker could use these flaws to crash any network service utilizing the MIT Kerberos GSS-API library to authenticate users or, possibly, leak portions of the service's memory. (CVE-2009-0844, CVE-2009-0845)
Alerts:	Mandriva MDVSA-2010:005 2010-01-13 Mandriva MDVSA-2009:098-1 2009-12-08 Mandriva MDVSA-2009:098 2009-04-27 Debian DSA-1766-1 2009-04-09 Gentoo 200904-09 2009-04-08 Ubuntu USN-755-1 2009-04-07 SuSE SUSE-SA:2009:019 2009-04-08 CentOS CESA-2009:0408 2009-04-08 CentOS CESA-2009:0409 2009-04-07 CentOS CESA-2009:0410 2009-04-07 Fedora FEDORA-2009-2852 2009-03-18 Fedora FEDORA-2009-2834 2009-03-18 rPath rPSA-2009-0058-1 2009-04-07 Red Hat RHSA-2009:0410-01 2009-04-07 Red Hat RHSA-2009:0409-01 2009-04-07 Red Hat RHSA-2009:0408-01 2009-04-07 Mandriva MDVSA-2009:082 2009-03-30

Comments (none posted)

nss-ldapd: insecure config file creation

Package(s):	nss-ldapd	CVE #(s):	CVE-2009-1073
Created:	March 31, 2009	Updated:	April 1, 2009
Description:	From the Debian advisory: Leigh James that discovered that nss-ldapd, an NSS module for using LDAP as a naming service, by default creates the configuration file /etc/nss-ldapd.conf world-readable which could leak the configured LDAP password if one is used for connecting to the LDAP server.
Alerts:	Debian DSA-1758-1 2009-03-30

Comments (none posted)

openssl: denial of service

Package(s):	openssl	CVE #(s):	CVE-2009-0590
Created:	March 31, 2009	Updated:	July 27, 2011
Description:	From the Ubuntu advisory: It was discovered that OpenSSL did not properly validate the length of an encoded BMPString or UniversalString when printing ASN.1 strings. If a user or automated system were tricked into processing a crafted certificate, an attacker could cause a denial of service via application crash in applications linked against OpenSSL.
Alerts:	SUSE SUSE-SU-2011:0847-1 2011-07-27 openSUSE openSUSE-SU-2011:0845-1 2011-07-27 CentOS CESA-2010:0163 2010-03-25 Red Hat RHSA-2010:0163-01 2010-03-25 CentOS CESA-2009:1335 2009-09-15 Red Hat RHSA-2009:1335-02 2009-09-02 SuSE SUSE-SR:2009:010 2009-05-12 Slackware SSA:2009-098-01 2009-04-08 Gentoo 200904-08 2009-04-07 Debian DSA-1763-1 2009-04-06 Mandriva MDVSA-2009:087 2009-04-03 rPath rPSA-2009-0057-1 2009-04-03 Ubuntu USN-750-1 2009-03-30

Comments (none posted)

openswan: denial of service

Package(s):	openswan	CVE #(s):	CVE-2009-0790
Created:	March 30, 2009	Updated:	September 9, 2009
Description:	From the Red Hat advisory: Gerd v. Egidy discovered a flaw in the Dead Peer Detection (DPD) in Openswan's pluto IKE daemon. A remote attacker could use a malicious DPD packet to crash the pluto daemon. (CVE-2009-0790)
Alerts:	Gentoo 200909-05 2009-09-09 SuSE SUSE-SR:2009:009 2009-04-21 CentOS CESA-2009:0402 2009-04-09 Debian DSA-1760-1 2009-03-30 Debian DSA-1759-1 2009-03-30 Red Hat RHSA-2009:0402-01 2009-03-30

Comments (none posted)

systemtap: race condition

Package(s):	systemtap	CVE #(s):	CVE-2009-0784
Created:	March 26, 2009	Updated:	April 2, 2009
Description:	systemtap has a race condition vulnerability. From the Debian alert: Erik Sjoelund discovered that a race condition in the stap tool shipped by Systemtap, an instrumentation system for Linux 2.6, allows local privilege escalation for members of the stapusr group.
Alerts:	CentOS CESA-2009:0373 2009-03-26 Red Hat RHSA-2009:0373-01 2009-03-26 Debian DSA-1755-1 2009-03-25

Comments (1 posted)

Page editor: Jake Edge

Kernel development

Brief items

Kernel release status

The current stable 2.6 kernel remains 2.6.29. The 2.6.30 merge window is open (see below), and no stable updates have been released over the last week.

The 2.6.29.1 stable update is in the review process as of this writing. This update, containing just over 40 fixes, can be expected around April 2 or 3.

Comments (none posted)

Kernel development news

Quotes of the week

-- Alan Cox

-- Andrew Morton

-- Linus Torvalds

Comments (2 posted)

2.6.30 merge window, part I

As of this writing, almost 6200 non-merge changesets have been added to the mainline for the 2.6.30 release. So the merge window is well and truly open. There's a lot of stuff set up for 2.6.30 already, with more certainly to come. The user-visible changes merged so far include:

• The relatime mount option is now the default; this means that file access times will only be updated if they are newer than the creation or modification times. Another change merged also causes the access time to be updated at least once per day. Users needing access times to be updated for every access can use the new "strictatime" mount option to get that behavior. See That massive filesystem thread for more information on this change.

• At long last, the integrity management patches have been merged. Among other things, this code can use the trusted platform module (TPM) to ensure that the files on a system have not been tampered with and to do remote attestation.

• Also at long last, TOMOYO Linux has been merged. TOMOYO is a pathname-based security module similar to (but significantly different from) AppArmor.

• There is a new cpuinfo_transition_latency sysfs variable for CPU frequency governors; it serves to inform user space of the time it takes for the CPU to transition from one frequency to another.

• There is now support for the new AES-NI cryptographic instructions being introduced into Intel processors; see this white paper [PDF] for details on AES-NI.

• The x86_64 and SuperH architectures have gained kexec jump support.

• There is a new guest debugging interface for KVM, allowing the host to do interactive debugging of guest systems. KVM has also gained support for PowerPC e500 processors.

• There is a new user-space API for detailed control over the timestamping of network packets. See Documentation/networking/timestamping.txt for details.

• The Reliable Datagram Sockets (RDS) protocol is now supported by the networking layer. See Documentation/networking/rds.txt for more information.

• The x86 architecture now has an option to put a "canary" value at the end of the kernel stack; if that value ever changes, the stack has been (accidentally or maliciously) overrun.

• The reiserfs filesystem has seen a burst of work which cleans up the code, improves SELinux support, and improves performance. This is likely to be the last set of updates for reiserfs.

• The usual array of new drivers has been merged. They include:
  • Block: PCI-Express SAS 6Gb/s host adapters.

  • Graphics: AMD R6xx/R7xx GPUs (2D only for now).

  • Networking: USB Qualcomm Serial modems, Marvell Libertas 8686 SPI 802.11b/g cards, Marvell 88w8xxx TOPDOG PCI/PCIe wireless cards, Prism54 SPI (stlc45xx) wireless adapters, Atmel at76c503/at76c505/at76c505a USB wireless adapters, OpenCores 10/100 Mbps Ethernet MAC devices, and Atheros "otus" 802.11n USB devices.

  • Sound: Mitac MIO A701 phones, Wolfson Micro WM8400 and WM9705 codecs, Wolfson Microelectronics 1133-EV1 modules, Atmel Audio Bitstream DAC devices, Atmel AC97 controllers, Asaki-Kasei AK4104 S/PDIF transmitters, Echo Audio IndigoIOx and IndigoDJx cards, Turtle Beach Classic, Fiji and Pinnacle cards, and Asus Xonar Essence STX sound cards.

  • Video/DVB: Mars-Semi MR97310A USB cameras, Freescale MC44S803 low power CMOS broadband tuners, SQ Technologies SQ905-based USB cameras, i.MX3x camera sensor interfaces, ST STV0900 satellite demodulators, ST STV6110 silicon tuners, SQ Technologies SQ905C-based USB cameras Zarlink ZL10036 silicon tuners, LG Electronics LGDT3305-based tuners, Hauppauge HD PVR USB devices, and Intel CE6230 DVB-T USB2.0 receivers.

  • Processors and systems: SuperH SH7786, ESPT-Giga SH7763-based reference boards, SMSC reference platform with a SH7709S CPUs, Palm LifeDrive and Tungsten|T5 systems, Brivo Systems LLC ACS-5000 master boards, Dave/DENX QongEVB-LITE platforms, Marvell RD-78x00-mASA development boards, Marvell PXA168 and PXA910 processors, TI OMAP850 processors, OMAP 3430 SDP boards, Nokia RX-51 internet tablets, Teltonika 3G Router RUT100 systems, Faraday FA526 cores, Cortina Systems Gemini family SoCs, GE Fanuc SBC310 and PPC9A PowerPC boards, Freescale Media5200 boards, AMCC Redwood(460SX) systems, Phytec phyCORE-MPC5200B-IO (pcm032) boards, and Freescale MPC8544 ("Socrates") boards.

  • Miscellaneous: AMCC PPC4xx crypto accelerators, Adrienne Electronics Corporation PCI time code devices, Symbol 6608 barcode scanners, E-Ink Broadsheet/Epson S1D13521 controllers, NXP Semiconductor PCA9665 i2c controllers, and Siemens Syleus and Hades sensor chips.

• The "Phidgets" USB drivers have been removed; users should shift to the user-space drivers instead.

Changes visible to kernel developers include:

• The adaptive spinning mutex patch has been merged. This change will cause mutexes to behave more like spinlocks in the contended case. If (and only if) the lock is held by code running on a different CPU, the mutex code will spin on the assumption that the lock will be released soon. This behavior results in significant performance improvements. Btrfs, which had its own spinning mutex implementation, has been converted to the new mutexes.

• There is a new set of functions added to the crypto API which allow for piecewise compression and decompression of data.

• The bus_id member of struct device is gone; code needing that information should use the dev_name() macro instead.

• There is a new timer function:

      int mod_timer_pending(struct timer_list *timer, unsigned long expires);
  

  It is like mod_timer() with the exception that it will not reactivate an already-expired timer.

• There have been some changes around the fasync() function in struct file_operations. This function is now responsible for maintaining the FASYNC bit in struct file; it is also now called without the big kernel lock held. Finally, a positive return value from fasync() is mapped to zero, meaning that the return value from fasync_helper() can be returned directly by fasync(). (This is your editor's modest contribution to 2.6.30).

• The SCSI layer has a new support library for object storage device support; see Documentation/scsi/osd.txt for details.

• The x86 "subarchitecture" mechanism has been removed, now that no architectures actually use it. The Voyager architecture has been removed as a result of these changes.

• x86 is also the first architecture to use a new per-CPU memory allocator merged for 2.6.30. This allocator changes little at the API level, but it will provide for more efficient and flexible per-CPU variable management.

• Support for compressing the kernel with the bzip2 or lzma algorithms has been added. Support for the old zImage format has been removed.

• The asynchronous function call infrastructure is now enabled by default.

• The DMA operations debugging facility has been merged.

• The owner field of struct proc_dir_entry has been removed, causing lots of changes throughout the tree.

If the usual two-week pattern holds, the merge window can be expected to remain open through about April 9. The rate at which changes flow into the mainline will likely be lower for the second half of the merge window - the alternative is for this development cycle to be far larger than any of its predecessors. But it is certain that more interesting changes will be merged for 2.6.30.

Comments (21 posted)

Flushing out pdflush

The kernel page cache contains in-memory copies of data blocks belonging to files kept in persistent storage. Pages which are written to by a processor, but not yet written to disk, are accumulated in cache and are known as "dirty" pages. The amount of dirty memory is listed in /proc/meminfo. Pages in the cache are flushed to disk after an interval of 30 seconds. Pdflush is a set of kernel threads which are responsible for writing the dirty pages to disk, either explicitly in response to a sync() call, or implicitly in cases when the page cache runs out of pages, if the pages have been in memory for too long, or there are too many dirty pages in the page cache (as specified by /proc/sys/vm/dirty_ratio).

At a given point of time, there are between two and eight pdflush threads running in the system. The number of pdflush threads is determined by the load on the page cache; new pdflush threads are spawned if none of the existing pdflush threads have been idle for more than one second, and there is more work in the pdflush work queue. On the other hand, if the last active pdflush thread has been asleep for more than one second, one thread is terminated. Termination of threads happens until only a minimum number of pdflush threads remain. The current number of running pdflush threads is reflected by /proc/sys/vm/nr_pdflush_threads.

A number of pdflush-related issues have come to light over time. Pdflush threads are common to all block devices, but it is thought that they would perform better if they concentrated on a single disk spindle. Contention between pdflush threads is avoided through the use of the BDI_pdflush flag on the backing_dev_info structure, but this interlock can also limit writeback performance. Another issue with pdflush is request starvation. There is a fixed number of I/O requests available for each queue in the system. If the limit is exceeded, any application requesting I/O will block waiting for a new slot. Since pdflush works on several queues, it cannot block on a single queue. So, it sets the wbc->nonblocking writeback information flag. If other applications continue to write on the device, pdflush will not succeed in allocating request slots. This may lead to starvation of access to the queue, if pdflush repeatedly finds the queue congested.

Jens Axboe in his patch set proposes a new idea of using flusher threads per backing device info (BDI), as a replacement for pdflush threads. Unlike pdflush threads, per-BDI flusher threads focus on a single disk spindle. With per-BDI flushing, when the request_queue is congested, blocking happens on request allocation, avoiding request starvation and providing better fairness.

With pdflush, The dirty inode list is stored by the super block of the filesystem. Since the per-BDI flusher needs to be aware of the dirty pages to be written by its assigned device, this list is now stored by the BDI. Calls to flush dirty inodes on the superblock result in flushing the inodes from the list of dirty inodes on the backing device for all devices listed for the filesystem.

As with pdflush, per-BDI writeback is controlled through the writeback_control data structure, which instructs the writeback code what to do, and how to perform the writeback. The important fields of this structure are:

• sync_mode: defines the way synchronization should be performed with respect to inode locking. If set to WB_SYNC_NONE, the writeback will skip locked inodes, where as if set to WB_SYNC_ALL will wait for locked inodes to be unlocked to perform the writeback.

• nr_to_write: the number of pages to write. This value is decremented as the pages are written.

• older_than_this: If not NULL, all inodes older than the jiffies recorded in this field are flushed. This field takes precedence over nr_to_write.

The struct bdi_writeback keeps all information required for flushing the dirty pages:

    struct bdi_writeback {
	struct backing_dev_info *bdi;
	unsigned int nr;
	struct task_struct	*task;
	wait_queue_head_t	wait;
	struct list_head	b_dirty;
	struct list_head	b_io;
	struct list_head	b_more_io;

	unsigned long		nr_pages;
	struct super_block	*sb;
    };

The bdi_writeback structure is initialized when the device is registered through bdi_register(). The fields of the bdi_writeback are:

• bdi: the backing_device_info associated with this bdi_writeback,

• task: contains the pointer to the default flusher thread which is responsible for spawning threads for performing the flushing work,

• wait: a wait queue for synchronizing with the flusher threads,

• b_dirty: list of all the dirty inodes on this BDI to be flushed,

• b_io: inodes parked for I/O,

• b_more_io: more inodes parked for I/O; all inodes queued for flushing are inserted in this list, before being moved to b_io,

• nr_pages: total number of pages to be flushed, and

• sb: the pointer to the superblock of the filesystem which resides on this BDI.

nr_pages and sb are parameters passed asynchronously to the the BDI flush thread, and are not fixed through the life of the bdi_writeback. This is done to facilitate devices with multiple filesystem, hence multiple super_blocks. With multiple super_blocks on a single device, a sync can be requested for a single filesystem on the device.

The bdi_writeback_task() function waits for the dirty_writeback_interval, which by default is 5 seconds, and initiates wb_do_writeback(wb) periodically. If there are no pages written for five minutes, the flusher thread exits (with a grace period of dirty_writeback_interval). If a writeback work is later required (after exit), new flusher threads are spawned by the default writeback thread.

Writeback flushes are done in two ways:

• pdflush style: This is initiated in response to an explicit writeback request, for example syncing inode pages of a super_block. wb_start_writeback() is called with the superblock information and the number of pages to be flushed. The function tries to acquire the bdi_writeback structure associated with the BDI. If successful, it stores the superblock pointer and the number of pages to be flushed in the bdi_writeback structure and wakes up the flusher thread to perform the actual writeout for the superblock. This is different from how pdflush performs writeouts: pdflush attempts to grab the device from the writeout path, blocking the writeouts from other processes.

• kupdated style: If there is no explicit writeback requests, the thread wakes up periodically to flush dirty data. The first time one of the inode's pages stored in the BDI is dirtied, the dirtying-time is recorded in the inode's address space. The periodic writeback code walks through the superblock's inode list, writing back dirty pages of the inodes older than a specified point in time. This is run once per dirty_writeback_interval, which defaults to five seconds.

After review of the first attempt, Jens added functionality of having multiple flusher threads per device based on the suggestions of Andrew Morton. Dave Chinner suggested that filesystems would like to have a flusher thread per allocation group. In the patch set (second iteration) which followed, Jens added a new interface in the superblock to return the bdi_writeback structure associated with the inode:

    struct bdi_writeback *(*inode_get_wb) (struct inode *);

If inode_get_wb is NULL, the default bdi_writeback of the BDI is returned, which means there is only one bdi_writeback thread for the BDI. The maximum number of threads that can be started per BDI is 32.

Initial experiments conducted by Jens found an 8% increase in performance on a simple SATA drive running Flexible File System Benchmark (ffsb). File layout was smoother as compared to the vanilla kernel as reported by vmstat, with a uniform distribution of buffers written out. With a ten-disk btrfs filesystem, per-BDI flushing performed 25% faster. The writeback is tracked by Jens's block layer git tree (git://git.kernel.dk/linux-2.6-block.git) under the "writeback" branch. There have been no comments on the second iteration so far, but per-BDI flusher threads is still not ready enough to go into the 2.6.30 tree.

Acknowledgments: Thanks to Jens Axboe for reviewing and explaining certain aspects of the patch set.

Comments (14 posted)

That massive filesystem thread

Long, highly-technical, and animated discussion threads are certainly not unheard of on the linux-kernel mailing list. Even by linux-kernel standards, though, the thread that followed the 2.6.29 announcement was impressive. Over the course of hundreds of messages, kernel developers argued about several aspects of how filesystems and block I/O work on contemporary Linux systems. In the end (your editor will be optimistic and say that it has mostly ended), we had a lot of heat - and some useful, concrete results.

One can only pity Jesper Krogh, who almost certainly didn't know what he was getting into when he posted a report of a process which had been hung up waiting for disk I/O for several minutes. All he was hoping for was a suggestion on how to avoid these kinds of delays - which are a manifestation of the famous ext3 fsync() problem - on his server. What he got, instead, was to be copied on the entire discussion.

Journaling priority

One of the problems is at least somewhat understood: a call to fsync() on an ext3 filesystem will force the filesystem journal (and related file data) to be committed to disk. That operation can create a lot of write activity which must be waited for. But contemporary I/O schedulers tend to favor read operations over writes. Most of the time, that is a rational choice: there is usually a process waiting for a read to complete, but writes can be done asynchronously. A journal commit is not asynchronous, though, and it can cause a lot of things to wait while it is in progress. So it would be better not to put journal I/O operations at the end of the queue.

In fact, it would be better not to make journal operations contend with the rest of the system at all. To that end, Arjan van de Ven has long maintained a simple patch which gives the kjournald thread realtime I/O priority. According to Alan Cox, this patch alone is sufficient to make a lot of the problems go away. The patch has never made it into the mainline, though, because Andrew Morton has blocked it. This patch, he says, does not address the real problem, and it causes a lot of unrelated I/O traffic to benefit from elevated priority as well. Andrew says the real fix is harder:

Bandaid or not, this approach has its adherents. The ext4 filesystem has a new mount option (journal_ioprio) which can be used to set the I/O priority for journaling operations; it defaults to something higher than normal (but not realtime). More recently, Ted Ts'o has posted a series of ext3 patches which sets the WRITE_SYNC flag on some journal writes. That flag marks the operations as synchronous, which will keep them from being blocked by a long series of read operations. According to Ted, this change helps quite a bit, at least when there is a lot of read activity going on. The ext3 changes have not yet been merged for 2.6.30 as of this writing (none of Ted's trees have), but chances are they will go in before 2.6.30-rc1.

data=ordered, fsync(), and fbarrier()

The real problem, though, according to Ted, is the ext3 data=ordered mode. That is the mode which makes ext3 relatively robust in the face of crashes, but, says Ted, it has done so at the cost of performance and the encouragement of poor user-space programming. He went so far as to express his regrets for this behavior:

The only problem here is that not everybody believes that ext3's behavior is a bad thing - at least, with regard to robustness. Much of this branch of the discussion covered the same issues raised by LWN in Better than POSIX? a couple of weeks before. A significant subset of developers do not want the additional robustness provided by ext3 data=ordered mode to go away. Matthew Garrett expressed this position well:

One option which came up a couple of times was to extend POSIX with a new system call (called something like fbarrier()) which would enforce ordering between filesystem operations. A call to fbarrier() could, for example, cause the data written to a new file to be forced out to disk before that file could be renamed on top of another file. The idea has some appeal, but Linus dislikes it:

And that is almost certainly how things will have to work. In the end, a system which just works is the system that people will want to use.

relatime

Meanwhile, another branch of the conversation revisited an old topic: atime updates. Unix-style filesystems traditionally track the time that each file was last accessed ("atime"), even though, in reality, there is very little use for this information. Tracking atime is a performance problem, in that it turns every read operation into a filesystem write as well. For this reason, Linux has long had a "noatime" mount option which would disable atime updates on the indicated filesystem.

As it happens, though, there can be problems with disabling atime entirely. One of them is that the mutt mail client uses atime to determine whether there is new mail in a mailbox. If the time of last access is prior to the time of last modification, mutt knows that mail has been delivered into that mailbox since the owner last looked at it. Disabling atime breaks this mechanism. In response to this problem, the kernel added a "relatime" option which causes atime to be updated only if the previous value is earlier than the modification time. The relatime option makes mutt work, but it, too, turns out to be insufficient: some distributions have temporary-directory cleaning programs which delete anything which hasn't been used for a sufficiently long period. With relatime, files can appear to be totally unused, even if they are read frequently.

If relatime could be made to work, the benefits could be significant; the elimination of atime updates can get rid of a lot of writes to the disk. That, in turn, will reduce latencies for more useful traffic and will also help to avoid disk spin-ups on laptops. To that end, Matthew Garrett posted a patch to modify the relatime semantics slightly: it allows atime to be updated if the previous value is more than one day in the past. This approach eliminates almost all atime updates while still keeping the value close to current.

This patch was proposed for merging, and more: it was suggested that relatime should be made the default mode for filesystems mounted under Linux. Anybody wanting the traditional atime behavior would have to mount their filesystems with the new "strictatime" mount option. This idea ran into some immediate opposition, for a couple of reasons. Andrew Morton didn't like the hardwired 24-hour value, saying, instead, that the update period should be given as a mount option. This option would be easy enough to implement, but few people think there is any reason to do so; it's hard to imagine a use case which requires any degree of control over the granularity of atime updates.

Alan Cox, instead, objected to the patch as an ABI change and a standards violation. He tried to "NAK" the patch, saying that, instead, this sort of change should be done by distributors. Linus, however, said he doesn't care; the relatime change and strictatime option were the very first things he merged when he opened the 2.6.30 merge window. His position is that the distributors have had more than a year to make this change, and they haven't done so. So the best thing to do, he says, is to change the default in the kernel and let people use strictatime if they really need that behavior.

For the curious, Valerie Aurora has written a detailed article about this change. She doesn't think that the patch will survive in its current form; your editor, though, does not see a whole lot of pressure for change at this point.

I/O barriers

Suppose you are a diligent application developer who codes proper fsync() calls where they are necessary. You might think that you are then protected against data loss in the face of a crash. But there is still a potential problem: the disk drive may lie to the operating system about having written the data to persistent media. Contemporary hardware performs aggressive caching of operations to improve performance; this caching will make a system run faster, but at the cost of adding another way for data to get lost.

There is, of course, a way to tell a drive to actually write data to persistent media. The block layer has long had support for barrier operations, which cause data to be flushed to disk before more operations can be initiated. But the ext3 filesystem does not use barriers by default because there is an associated performance penalty. With ext4, instead, barriers are on by default.

Jeff Garzik pointed out one associated problem: a call to fsync() does not necessarily cause the drive to flush data to the physical media. He suggested that fsync() should create a barrier, even if the filesystem as a whole is not using barriers. In that way, he says, fsync() might actually live up to the promise that it is making to application developers.

The idea was not controversial, even though people are, as a whole, less concerned with caches inside disk drives. Those caches tend to be short-lived, and they are quite likely to be written even if the operating system crashes or some other component of the system fails. So the chances of data loss at that level are much smaller than they are with data in an operating system cache. Still, it's possible to provide a higher-level guarantee, so Fernando Luis Vazquez Cao posted a series of patches to add barriers to fsync() calls. And that is when the trouble started.

The fundamental disagreement here is over what should happen when an attempt to send a flush operation to the device fails. Fernando's patch returned an ENOTSUPP error to the caller, but Linus asked for it to be removed. His position is that there is nothing that the caller can do about a failed barrier operation anyway, so there is no real reason to propagate that error upward. At most, the system should set a flag noting that the device doesn't support barriers. But, says Linus, filesystems should cope with what the storage device provides.

Ric Wheeler, instead, argues that filesystems should know if barrier operations are not working and be able to respond accordingly. Says Ric:

Alan Cox also jumped into this discussion in favor of stronger barriers:

Linus appears to be unswayed by these arguments, though. In his view, filesystems should do the best they can and accept what the underlying device is able to do. As of this writing, no patches adding barriers to fsync() have been merged into the mainline.

Related to this is the concept of laptop mode. It has been suggested that, when a system is in laptop mode, an fsync() call should not actually flush data to disk; flushing the data would cause the drive to spin up, defeating the intent of laptop mode. The response to I/O barrier requests would presumably be similar. Some developers oppose this idea, though, seeing it as a weakening of the promises provided by the API. This looks like a topic which could go a long time without any real resolution.

Performance tuning

Finally, there was some talk about trying to make the virtual memory subsystem perform better in general. Part of the problem here has been recognized for some time: memory sizes have grown faster than disk speeds. So it takes a lot longer to write out a full load of dirty pages than it did in the past. That simple dynamic is part of the reason why writeout operations can stall for long periods; it just takes that long to funnel gigabytes of data onto a disk drive. It is generally expected that solid-state drives will eventually make this problem go away, but it is also expected that it will be quite some time, yet, before those drives are universal.

In the mean time, one can try to improve performance by not allowing the system to accumulate as much data in need of writing. So, rather than letting dirty pages stay in cache for (say) 30 seconds, those pages should be flushed more frequently. Or the system could adjust the percentage of RAM which is allowed to be dirty, perhaps in response to observations about the actual bandwidth of the backing store devices. The kernel already has a "percentage dirty" limit, but some developers are now suggesting that the limit should be a fixed number of bytes instead. In particular, that limit should be set to the number of bytes which can be flushed to the backing store device in (say) one second.

Nobody objects to the idea of a better-tuned virtual memory subsystem. But there is some real disagreement over how that tuning should be done. Some developers argue for exposing the tuning knobs to user space and letting the distributors work it out. Andrew is a strong proponent of this approach:

The objections to that approach follow these lines: the distributors cannot get these numbers right; in fact, they are not really even inclined to try to get them right. The proper tuning values tend to change from one kernel to the next, so it makes sense to keep them with the kernel itself. And the kernel should be able to get these things right if it is doing its job at all. Needless to say, Linus argues for this approach, saying:

Linus has suggested (but not implemented) one set of heuristics which could help the system to tune itself. Neil Brown also has a suggested approach, based on measuring the actual performance of the system's storage devices. Fixing things at this level is likely to take some time; virtual memory changes always do. But some smart people are starting to think about the problem, and that's an important first step.

That, too, could be said for the discussion as a whole. There are clearly a lot of issues surrounding filesystems and I/O which have come to the surface and need to be discussed. The Linux kernel community as a whole needs to think through the sort of guarantees (for both robustness and performance) it will offer to its users and how those guarantees will be fulfilled. As it happens, the 2009 Linux Storage & Filesystems Workshop begins on April 6. Many of these topics are likely to be discussed there. Your editor has managed to talk his way into that room; stay tuned.

Comments (72 posted)

Patches and updates

Kernel trees

• Thomas Gleixner: 2.6.29-rt1 . (March 26, 2009)

Core kernel code

• Ingo Molnar: scheduler updates for v2.6.30 . (March 26, 2009)

• Ingo Molnar: timer updates for v2.6.30 . (March 26, 2009)

• Ingo Molnar: locking updates for v2.6.30 . (March 30, 2009)

• Arjan van de Ven: async / fast boot patches . (March 30, 2009)

• Rusty Russell: module and parameter patches . (March 30, 2009)

• Ingo Molnar: printk changes for v2.6.30 . (March 30, 2009)

• Paul E. McKenney: v3 RCU: the bloatwatch edition . (March 30, 2009)

• Darren Hart: requeue pi implementation . (March 30, 2009)

• Gautham R Shenoy: sched: Extend sched_mc/smt_power_savings framework. . (March 31, 2009)

• Oren Laadan: Kernel based checkpoint/restart . (March 31, 2009)

• Arun R Bharadwaj: timers: Framework for migration of timers . (April 1, 2009)

Development tools

• Josh Stone: systemtap release 0.9.5 . (March 27, 2009)

• Subrata Modak: The Linux Test Project has been Released for MARCH 2009 . (March 31, 2009)

Device drivers

• Oskar Schirmer: add pca9543 driver . (March 26, 2009)

• James Bottomley: first set of SCSI updates for the 2.6.30 merge window . (March 27, 2009)

• Vladislav Bolkhovitin: : SCST target drivers suit 1.0.1 development freeze . (March 27, 2009)

• Bartlomiej Zolnierkiewicz: IDE updates part 2 . (March 30, 2009)

• Bartlomiej Zolnierkiewicz: IDE updates part 3 . (March 31, 2009)

• Mauro Carvalho Chehab: V4L/DVB improvements for 2.6.30 . (March 30, 2009)

• James Smart: FC Pass Thru support . (March 30, 2009)

• Darius Augulis: Add camera (CSI) driver for MX1 . (March 30, 2009)

• Kevin Cernekee: MTD: New ioctl calls for >4GiB device support . (March 31, 2009)

• Jiri Kosina: HID updates for 2.6.30-rc1 . (March 31, 2009)

• Grant Likely: Add common OF device tree support for MDIO busses . (March 31, 2009)

• Jesse Barnes: PCI changes for 2.6.30 . (March 31, 2009)

• Eduardo Valentin: FM Transmitter driver . (April 1, 2009)

Documentation

• Michael Kerrisk: man-pages-3.20 is released . (March 30, 2009)

Filesystems and block I/O

• Theodore Ts'o: Ext4 tree stable patches backports for 2.6.27 and 2.6.28 . (March 26, 2009)

• Theodore Ts'o: Ext3 latency improvement patches . (March 27, 2009)

• Theodore Ts'o: ext4 updates for 2.6.30 . (April 1, 2009)

• Al Viro: vfs - first pile . (March 30, 2009)

• npiggin@suse.de: scale dcache locking . (March 30, 2009)

• Philipp Reisner: DRBD: a block device for HA clusters . (March 30, 2009)

• Artem Bityutskiy: EXT4-ish "fixes" in UBIFS . (March 30, 2009)

• Jeff Mahoney: Jeff's ReiserFS Patch Queue . (March 30, 2009)

• Miklos Szeredi: fuse: implement missing functionality on "direct_io" files . (March 30, 2009)

• Felix Blyakher: XFS update for 2.6.30 . (March 31, 2009)

• NeilBrown: Final set of MD patches head for 2.6.30 . (March 31, 2009)

• Chris Mason: Btrfs updates for 2.6.30-rc . (March 31, 2009)

• Boaz Harrosh: exofs for 2.6.30 (really) . (April 1, 2009)

Memory management

• Nitin Gupta: compressed in-memory swapping take4 . (March 30, 2009)

• Izik Eidus: ksm - dynamic page sharing driver for linux . (March 31, 2009)

Networking

• David Miller: : Networking for 2.6.30 . (March 26, 2009)

• David Miller: : Networking . (March 30, 2009)

• Evgeniy Polyakov: Passive OS fingerprint xtables match. . (March 30, 2009)

• Patrick McHardy: netfilter 00/12: Netfilter fixes/2.6.30 update part II . (March 30, 2009)

• Johannes Berg: rfkill: rewrite . (March 30, 2009)

Architecture-specific

• Ingo Molnar: x86 updates for v2.6.30, stage 1 . (March 27, 2009)

• Ingo Molnar: x86 updates for v2.6.30, final bits . (March 30, 2009)

• Michal Simek: Microblaze initial pack . (March 27, 2009)

• Jeremy Fitzhardinge: Allow preemption during lazy mmu updates . (March 30, 2009)

Security-related

• Jari Ruusu: Announce loop-AES-v3.2f file/swap crypto package . (March 30, 2009)

• Paul Moore: Labeled networking patches for 2.6.30 . (March 30, 2009)

• Joseph Cihula: intel_txt: Intel(R) TXT and tboot kernel support . (March 31, 2009)

Virtualization and containers

• KAMEZAWA Hiroyuki: memcg soft limit (yet another new design) v1 . (March 27, 2009)

• Joerg Roedel: Support for GB pages in KVM . (March 27, 2009)

• Martin Schwidefsky: Guest page hinting version 7. . (March 27, 2009)

• Rusty Russell: lguest and virtio patches . (March 30, 2009)

• Jeremy Fitzhardinge: Xen for 2.6.30 #2 . (March 31, 2009)

• Gregory Haskins: virtual-bus . (March 31, 2009)

Miscellaneous

• Theodore Ts'o: 2009 Linux Kernel Summit . (March 27, 2009)

• Andreas Robinson: lib, initramfs: Add initramfs LZO compression . (April 1, 2009)

• Pablo Neira Ayuso: conntrack-tools 0.9.12 released . (April 1, 2009)

• Jan Engelhardt: Xtables-addons 1.14 . (April 1, 2009)

• Nigel Cunningham: TuxOnIce 3.0. (April 1, 2009)

Page editor: Jonathan Corbet

Distributions

News and Editorials

Debian Project Leader Election Quiet This Year

This year, the election of the Debian Project Leader (DPL) is proving more sedate than in previous years. The change, perhaps, reflects the diminished importance of the distribution, or the efforts over the last few years to increase civility within the project. Or possibly the change is due to the fact that only two candidates are running — Stefano Zacchiroli and incumbent Steve McIntyre, two long time project members who respect one another. But, for whatever reason, this years DPL election is noteworthy mainly for its civility. Zacchiroli and McIntyre share many views, and, on many others, differ mainly in emphasis. The result is that the election will likely be decided mainly on personality and management style rather than issues.

As outlined in the Debian Constitution, the DPL is elected each year. The election begins with a week long nomination period, followed by a three week campaign period and a two week voting period. Only official Debian Developers can vote, and results are tallied by the Project Secretary using a Condorcet method, in which the winner is the candidate who would beat each of the other candidates in a run-off election (although, this year, the results will be the same as a simple majority vote, since there are only two candidates). This year, voting began on March 29, and is scheduled to end on April 11, a second before midnight UTC.

The Candidates: Steve McIntyre

Steve McIntyre, the current DPL, has been a Debian Developer since 1996. According to his election platform, his main contribution to Debian is as a member of the CD Team, "both developing the debian-cd software itself and using that same software to create the official CDs." In addition, McIntyre hosts servers on Debian's autobuilder network for building packages for multiple hardware architectures, and helps to administer the project's Summer of Code program.

McIntyre ran largely on his record in his present term. In his platform, he emphasized how, in the past year, he organized a review of how various Debian teams were performing. To try to improve inefficient teams, he has tried to recruit new members and suggest new work methods. He also emphasized communication, saying that he has helped resolve disputes within the project, and represented Debian at trade fairs, as well as to the press and other free software groups. He listed "communications within the project. The Debian community tends to discuss everything publicly and at great lengths, but, this year, debian-vote seems subdued compared to previous years." as his first goal in a new term, followed by finding ways to improve processes within the project, such as the one by which new maintainers join the project.

However, McIntyre did not specify how he would approach these goals. Instead, he simply said, "I want to see improvements made where they are clearly needed. There are cases where communications are lacking, or people and teams might not be working as effectively as they want to or need to. In those cases, I want to help and encourage the people involved to make those improvements. If that is not enough, then we may need stronger actions."

Rather than focusing on details, McIntyre urged people to vote for him on the basis of his experience, his organizational work, and his personality. "I'm a programmer, which means I have strong opinions on many subjects (*grin*). Despite that, I believe I am honest, generally approachable and easy to work with. I am a good communicator and negotiator, and I have made many friends in the Debian and wider Free Software Community over the years."

The Candidates: Stefano Zacchiroli

Stefano Zacchiroli, better known as "Zack," has been a Debian developer since 2001. He maintains a number of packages related to OCaml and Vim as well as "tools for mathematics in XML, [and] Python libraries for dealing with XML," according to his platform.

In contrast to McIntyre's statement, Zacchiroli's statement was much more organized and concrete. Even so, it is at least twice as long, listing key points in bullet lists and listing specific actions he wants to take. These key point range from a promise to be "transparent and present," responsible for setting the project agenda, and active in communicating his activities to the rest of the project to encouraging consensus and the control of "vocal minorities" in discussions, and finding new ways in which new developers and non-programmers can become more active more quickly. He also promised to encourage face-to-face meetings, to see that core teams within the project consist of at least three members, and to encourage members of inactive or poorly organized teams to find a replacement and "something to work on that is more fun for them."

While Zacchiroli's platform included such concrete ideas as methods for continuing to improve the levels of politeness on mailing lists and redesigning the web site, a large part of it centered on the role of the DPL. In Zacchiroli's view, the DPL is responsible for conflict resolution within the project. He explained that, while he will not be a "'post-in-every-thread' DPL" that he "will try to be present in 'hot' discussions . . . which concern the organization and the big picture of the project. I will also encourage seeking the DPL opinion on specific topics by pinging me explicitly. The DPL['s] opinion can also be a reasonable first attempt to solve a conflict; if it fails, we do have other mechanisms to settle it." He suggested that these proposals will be aided by his personality: "I am thoughtful, listen to others, and open to be convinced by good arguments."

Campaign Issues

For those who want details about the campaigning, Zacchiroli provides a convenient summary of most of the questions raised on the debian-vote mailing list during the campaign period.

However, for those hoping to differentiate the candidates by their stands on the issues, debian-vote offers little help. McIntyre and Zacchiroli are in broad agreement on many — even most — subjects, including the use of non-sexist language in standard project documents. Both agree that collaborative package management is desirable, particularly as a way to help new maintainers gain experience, and that important packages should usually have core teams to maintain them. Similarly, the two candidates are in broad agreement that Debian's reserve funds of some $125,000 could be greatly reduced, although McIntyre suggests that they be halved, and Zacchiroli suggests that they could be reduced to $50,000.

One small difference that emerges on debian-vote is the role of the DPL in discussions of policies and actions: Zacchiroli sees the DPL as the leader of discussions who sets the agenda, while McIntyre favors a less direct approach of encouraging sensible people to voice their opinions whenever possible. However, this is a difference in approach, not a dispute over whether anything needs to be done.

Even McIntyre's announcement of Luk Claes, another long-time Debian Developer, as a running mate has not been much of issue. The idea that the DPL needs trusted assistants is not a new one; for instance, in 2005, Branden Robinson and Andreas Schuldei ran, promising that if either was elected, he would be assisted by "Project SCUD" — a group of half a dozen long-time Debian contributors. However, while Project SCUD was controversial in its day, nobody has publicly expressed a comparable level of concern that McIntyre proposed a kind of partnership that the Debian Constitution does not explicitly provide for, explaining that he and Claes are "planning on splitting the workload between us, depending on what fits and who has the time at any given point. My plan is for both of us to receive leader@mail."

Most likely, the proposal is uncontroversial because Zacchiroli's position is not far from McIntyre's. Although Zacchiroli said in his platform that he does not believe in a "DPL board" because "the DPL term is too short to spend time with extra coordination hops," he immediately moved closer to McIntyre's position by adding that he "will be looking for a 2IC (second in charge, vice-leader)." This admission led McIntyre to add a rebuttal to his own platform: "That I can understand completely, but I'd be personally much happier if he was to name his proposed assistant before the election. I did that deliberately with Luk, as I want people to be able to vote for a known quantity rather than somebody unnamed."

The largest difference between the candidates is in their answers to the question of what actions will improve Debian the most. In reply to the question, Zacchiroli wrote, "When I joined in 2001, Debian was The Distribution that a lot of users were using and all my friends knowing Free Software were dreaming of contributing to. Things have changed since then: newbies now use Ubuntu or Fedora, and contributors can easily join their communities. Debian is too often seen as the old distro that some old timers still use, having a process to join which is not worth trying. The Debian value that needs to be improved the most is changing that: putting Debian back into its place." Zacchiroli maintains that, within a year, Debian can set an example for the rest of the free software community, particularly in contributing changes to upstream projects.

In comparison, McIntyre replied to the question by writing about improving communication both inside and outside the project. "We need to encourage more people to experiment with new ideas, rather than simply live with the status quo all the time. Larger projects have inertia, and we have to acknowledge that: either push things more to overcome it, or work around it for the new ideas until they're ready for wider adoptions." He added that "the most important thing we need to do is to work out exactly what we want the Debian project to be, in terms of leadership. Making it clearer and easier for people to gain recognition for whatever work they're doing on or with Debian is far and away the best way to encourage more people to get involved." Noticeably, though, the solution for both candidates to the main problem that they see is to improve coordination within and without the project, the only difference being the reasons they want to do so.

Conclusion

Rather than attack each other's policies, both McIntyre and Zacchiroli tried to point out the weakness in each other's statements. For instance, in the rebuttal added to the end of his platform statement, Zacchiroli attempts to characterize Claes and McIntyre's candidacy as vague, claiming that "their platform lacks hints and strategies that explain how they are going to attack those problems . . . . Also, I'm missing the vision of the two candidates on relevant topics such as Debian membership, mailing list discussion quality, [and] derivatives [distributions based on Debian]."

For his part, McIntyre attempted in his own rebuttal to counter Zacchiroli's bullet lists by saying, "I'm not sure he will have the time to do what he's planning: time always runs away more quickly than you expect" — a comment that serves to remind voters of his own experience as DPL.

After you read McIntyre's and Zacchiroli's comments, you soon realize that there is no major difference of opinion between them. When you find an apparent one, on close examination, it tends to be a matter of emphasis at a particular time more than anything approaching a major disagreement. In fact, one candidate's answer in a particular context often echoes the other's answers in another. Both show an awareness of issues and maturity that could make an effective DPL.

The main question about this years' election, apart from who wins, is whether such reasonableness will affect voter turnout. Although many decry the acrimony of previous elections, it may have encouraged people to discuss issues and vote. This years' reasonableness seems to have reduced discussion on debian-vote (always taking into account the Debian community's tendency to discuss everything publicly and at great length) and the possibility seems strong that the number of votes cast could be similarly reduced. We'll know some time in the early hours of April 12 when the results are announced.

Comments (5 posted)

New Releases

CentOS 5.3 released

The CentOS 5.3 release is available. "CentOS-5.3 is based on the upstream release EL 5.3.0, and includes packages from all variants including Server and Client. All upstream repositories have been combined into one, to make it easier for end users to work with. And the option to further enable external repositories at install time is now available in the installer." See the release notes for more information.

Full Story (comments: 8)

Fedora 11 beta release available

The Fedora 11 beta release has been announced. "The larger open source community, beyond just developers and Fedora contributors, can download, test, and report issues, which should substantially improve the final release. Fedora even provides convenient Live images that testers can write to either CD/DVD, or to a USB key. Windows users can also make Live USB keys using the easy LiveUSB Creator application." See the Fedora 11 feature list for information on some of the new stuff in this release.

Comments (none posted)

Ubuntu 9.04 Beta released

Ubuntu Jaunty Jackalope (9.04) beta is available for testing. In particular, there is a call for testing suspend/resume. For those who have already downloaded Jaunty beta, beware of a python upgrade with some problems. The bad packages have been blocked and fixed packages have been uploaded, so make sure you have the correct python 2.6 packages.

Full Story (comments: none)

Distribution News

Debian GNU/Linux

First call for votes for the Debian Project Leader Elections 2009

The voting period has begun in the this year's Debian Project Leader elections. There are three choices available: Stefano Zacchiroli, Steve McIntyre (the current DPL) or neither. Voting will be open until April 11, 2009.

Full Story (comments: none)

Fedora

Reminder: Fedora Board IRC meeting 1800 UTC 2009-04-07

The Fedora Advisory Board is holding its monthly public meeting on Tuesday, 7 April 2009, at 1800 UTC on IRC Freenode. "We're trying something new (albeit in a minor way) in this meeting. The moderator will still be available to gather input from the #fedora-board-public channel, but will voice people, one at a time, in the queue in the #fedora-board-meeting channel. We'll limit time per voice as needed to give everyone in the queue a chance to be heard. If this process works well, we'll use it at later meetings and note the change on the wiki." Public meetings will be held on the first Tuesday of each month.

Full Story (comments: none)

Gentoo Linux

Gentoo Council Meeting Summary

Click below for a summary of the March 26, 2009 meeting of the Gentoo council. Topics include GLEP 55 and EAPI-3 Proposals.

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Ubuntu family

Packaging Training Sessions

The Ubuntu Developer Community has announced a new initiative to help those interested in developing Ubuntu. "Thursday is from now on Packaging Training day. We'll have regular one-hour sessions in #ubuntu-classroom on irc.freenode.net where we'll have speakers who present a packaging technique and leave enough time for all packaging related questions you might have." Click below for the April schedule.

Full Story (comments: none)

Other distributions

LynuxWorks' BlueCat 5.6 Supports Portwell's PEB-2737 Embedded Computer Board

LynuxWorks has announced that BlueCat 5.6 Linux operating system now supports Portwell's commercial off the shelf PEB-2737 embedded computer board. "Utilizing an Intel Embedded Compact Extended form factor, the PEB-2737 leverages Intel's Z510/Z530 Atom processor series by providing an optimized micro-architecture for low power, compact and fanless devices and when combined with LynuxWorks' BlueCat Linux, is a basis for applications in in-vehicle infotainment, medical, military and industrial automation and control."

Comments (none posted)

Distribution Newsletters

DistroWatch Weekly, Issue 296

The DistroWatch Weekly for March 30, 2009 is out. "After last week's interview with Tiny Core's Robert Shingledecker, the latest issue of DistroWatch Weekly takes a first look at the world's smallest desktop Linux distribution. Can a 10 MB distro be turned and tweaked into a powerful desktop replacement? Read on to find out. In the news, PCLinuxOS has seen developers leave the popular distribution over internal conflicts due to issues around the latest release. This has also caused ripples as TinyMe decides to move away from PCLinuxOS as their base. In the meanwhile, the administrator of a PCLinuxOS community web site has announced that he will no longer be involved with PCLinuxOS and will instead work on a new distribution called Unity. In other news, OpenSolaris posts major improvements to their package management system, Fedora calls for testing the open-source Nouveau driver, and the founder of Qimo 4 Kids explains the purpose of the young distribution designed for children. All this and more in this issue of DistroWatch Weekly - happy reading!"

Comments (none posted)

Fedora Weekly News #169

The Fedora Weekly News for the week ending March 29, 2009 is out. "This week in "What Happened Last Summer?" Developments conveys an announcement on the Fedora intrusion of 2008. Announcements reels-off a list of interesting "Upcoming Events". PlanetFedora selects choice blog posts including Richard W.M. Jones' RPM-dependency visualizer. Marketing reports that "Fedora has the Most New Features". Ambassadors reports that "Fedora is on the move in Italy". QualityAssurance shares the results of "Test Days" for the nouveau driver and other outstanding work. Translation catches-up on problems with Persian l10n and more. Artwork asks is it too late for "A Lion for Leonidas?". Security warns of a "Firefox Emergency". Virtualization concludes that "KVM and QEMU Merge Feature Stays in Fedora 11" and on "Web Based libvirt Management" and a comprehensive "Fedora Virtualization Status Report"."

Full Story (comments: none)

openSUSE Weekly News #65

This issue of the openSUSE Weekly News covers an Update on iFolder, openSUSE Weekly News @ RadioTux.de, People of openSUSE is back, OpenSource meet Business, My GIMP Tutorial and Resource and more.

Comments (none posted)

Ubuntu Weekly Newsletter #135

The Ubuntu Weekly Newsletter for the week ending March 28, 2009 is out. "In this issue we cover: Ubuntu 9.04 Beta Released, Jaunty Countdown Banners, Ubuntu 7.10 reaches EOL April 18th, Ubuntu Server dedicated course, QA Team Testing Day: Ubuntu Installers, Ubuntu Makassar, Ubuntu Tunisia, Ubuntu New York, Ubuntu LoCo Drupal 6.3.1 released, Launchpad Maintenance April 1st, Linking project releases in Launchpad to Milestones, LinkedIn for Ubuntu Members, Ubuntu 9.04 Free Culture Showcase Winners, The Fridge needs a new theme, LWN subscription for Ubuntu Members, Ubuntu Podcast #23 and an interview with John Pugh(Canonical Technical Partner Mgr.), Full Circle Magazine #23, March 2009 Team Reports, and much, much more!"

Full Story (comments: none)

Distribution meetings

openSUSE Project at LinuxExpo in Prague

Look for the openSUSE project at LinuxExpo in Prague. "The openSUSE Project is bringing the green to Prague in April! The openSUSE Project will have a booth, demos, and several presentations at the LinuxExpo in Prague, April 15 and 16th at the Hotel Olympik Artemis."

Full Story (comments: none)

openSUSE Conference

The openSUSE Project will be having its first contributor's conference, September 17 - 20, 2009 in Nuremberg, Germany. "If you're interested in being part of the conference team, speak up on the opensuse-marketing mailing list. We're looking for contributors to help with speaker selection, event staff, video recording talks and sessions, and much more. See the wiki for more help, and add your name if you're interested in being part of the conference team."

Comments (none posted)

Distribution reviews

Novell's SUSE Linux Enterprise Desktop 11: A true Windows replacement (Computerworld)

Computerworld reviews SUSE Linux Enterprise Desktop 11. "There are lots of Linux distros being touted as great desktop operating systems for PCs. However, there's only one that I can wholeheartedly recommend to business owners as a Windows replacement: Novell's SUSE Linux Enterprise Desktop 11 (SLED). SLED 11, which was released on March 24, stands above its competitors because it works and plays well with existing Windows business networks, data files and application servers. You can, of course, add this functionality to other Linux distributions -- if you're willing to do it manually. SLED gives you pretty much the full deal out of the box."

Comments (none posted)

Jackalope sighting: first look at Ubuntu 9.04 beta (ars technica)

ars technica reviews Ubuntu 9.04 beta. "All things considered, Ubuntu 9.04 is shaping up to be a pretty good release, albeit a bit light on new features. I've been running the it since the beginning of the month, when I installed it from a daily CD image. I've only had a few minor problems with it and it's definitely on track to be much more robust than the last two versions. I'm having significantly fewer problems with Compiz and PulseAudio. I've also noticed that boot performance in 9.04 is excellent, as my system starts up much faster."

Comments (none posted)

Novell Desktop Linux: Solid, But Lacks Features (eWeek Europe)

Jason Brooks takes a look at SUSE Linux Enterprise Desktop (SLED). "Based on my tests so far of SLED 11, I've found Novell's new Linux offering to be a solid desktop operating system with a set of features and support options that are well tuned for enterprises - particularly those looking to integrate the Linux desktop into a Microsoft-centric infrastructure."

Comments (none posted)

Page editor: Rebecca Sobol

Development

ConVirt 1.0

Simultaneously running multiple operating systems on one computer has been a common practice for decades on mainframes, but is now commonly used on all classes of machines. This can be used for server consolidation: many underutilized physical servers are replaced by one powerful physical server hosting different virtual machines. However, this doesn't make management of the (now virtual) servers easier. To the contrary: as more and more servers are virtualized, system administrators could lose the "big picture" of their server farm. Good administration tools for virtualization are priceless.

After many months of development and bug-fixing, the developers of ConVirt have released version 1.0 of their graphical management tool for virtual machine life cycle management. This tool, in a previous life called XenMan, offers a solution to install ("provision" in virtualization lingo), monitor and manage the complete lifecycle of Xen and KVM deployments from a central dashboard. ConVirt is an open source product, aimed at the enterprise market. The company Convirture offers paid support, but free support is available through the community forums and wiki.

Managing a set of virtual machines manually is a time-consuming and error-prone task. Many system administrators write their own custom provisioning scripts to handle this, but then the problem of keeping track of all these virtual machines and monitoring them pops up. ConVirt manages both Xen and KVM from a single interface and shields the low-level differences between these virtualization platforms from the user. This means users don't need to learn and use multiple tools if different virtual machines use a different virtualization platform. Installing, configuring and monitoring virtual machines is all possible from a single dashboard. Most of the tasks, such as migrating virtual machines, taking snapshots or adding storage, are possible with a few clicks.

Preparation

Preparing an environment of virtual machines for ConVirt happens in three steps: install ConVirt on one computer, prepare each server to be managed by ConVirt, and then start ConVirt, after which it discovers the prepared managed servers. The second step may be skipped if all managed virtual machines reside on the same computer as ConVirt.

Before the preparation, one should take a couple of things into account. ConVirt can be installed on most Linux systems, but it is only tested on a couple of distributions. Convirture has certified ConVirt on CentOS or Red Hat Enterprise Linux 5.2 with Xen 3.1, SUSE Linux Enterprise Server 10 SP2 with Xen 3.2, Debian 5.0 with KVM-72 and Ubuntu Server/Desktop 8.10 with KVM-72. The community has tested ConVirt successfully on some other configurations. The remotely managed servers should have a supported version of Xen or KVM, and should be accessible by SSH.

The wiki has specific installation instructions for a few Linux distributions. Your author applied them successfully on an Ubuntu 8.10 Desktop with KVM. On each server, download the convirture-tools package and run:

    convirt-tool setup 

to configure the server. For Xen, this command configures the Xend Server to listen on port 8006 and to open port 8002 for migration. The setup tool writes a summary of its operations to the /var/cache/convirt/server_info file for later reference. ConVirt doesn't require deploying a software agent on the managed servers because it uses SSH.

Virtual infrastructure

ConVirt supplies a wealth of monitoring information at multiple levels: the individual virtual machine, the physical server. and the server pool. The user sees performance, utilization, and availability metrics for the CPU, memory, storage, and network. This gives one a good overview to decide where adjustments need to be made to capacity or to reallocate resources.

The concept of a server pool is central in ConVirt's operation, to the point that the user can install, configure, and monitor virtual machines at the server pool level. Key monitoring information for different servers of the pool is summarized to a pool-wide value. In the same way one can change the pool-wide configuration, which ConVirt then applies to all servers in the pool. It's also possible to associate shared storage (SAN or NAS) with a server pool. All virtual machines on this server pool then use the same storage settings.

Adding a server to a server pool is simple: select a server pool in ConVirt and right-click to select 'Add Server'. Choose Xen or KVM as the virtualization platform and enter the IP address or hostname of the server, provide the username and password for SSH and press OK. After this, the server shows up under the server pool and is ready to host virtual machines.

Virtual appliances

Templates are central to ConVirt's provisioning capabilities: the tool comes with a couple of templates, which are easily customizable. ConVirt creates two default groups in the image store: Xen Paravirtual, which contains virtual machine images for the Xen platform, and Common, which contains images that can be deployed on Xen or KVM if the processor supports virtualization. The Xen image store comes with templates for a CentOS or Fedora installation, and the Common image store has templates for a generic Linux or Windows installation.

Of course it is possible to create a template based on your own image or a third-party virtual appliance. An interesting feature is the integrated virtual appliance catalog browser: ConVirt searches on the websites of a number of appliance vendors (at this moment only rPath and JumpBox) of virtual appliances. Users can browse the catalog and download the right appliance, which can then be installed in ConVirt.

The rest of the configuration of a template comes down to allocating CPU, memory and storage, and defining the network. Installing a template into a new or existing server is a one-click action. If a user has a lot of servers with different workloads, ConVirt is able to identify the optimal placement in the server pool, taking into account the performance and workload of the various servers. Migrating a virtual machine between servers couldn't be easier: with a simple drag-and-drop move, the user can move a virtual machine from one server to another while it's running and without interrupting operations. The same holds for a whole group of virtual machines, for example if the server is upgraded or down for maintenance.

ConVirt 1.0 also allows dynamic configuration of CPU and memory resources for live virtual machines. In the future the project intends to add a policy-based mechanism to allow a more elastic pre-configuration and enforcement of resource limits.

Conclusion and future direction

ConVirt is an interesting solution for system administrators with a lot of servers and virtual machines to manage. One central dashboard to install, monitor and manage virtual machines should be more than welcome. On the server side there is virtually no extra work: a user only needs to run the setup tool once to configure the server correctly.

ConVirt is fully open source, and Convirture actively encourages the community to discuss, give feedback, and make suggestions as well as contribute directly to the codebase. Convirture's founder Arsalan Farooq said that they have received several key contributions from outside Convirture, but he admits that the majority of the code has been contributed by his company. His hope is that this ratio will change going forward in favor of even more community contributions.

At this moment, ConVirt supports Xen and KVM, but the management tool has a plugin architecture that allows new platforms to be added easily. According to Farooq, the ConVirt developers will continue to add support for any relevant open source virtualization platforms that might emerge, and he mentioned Red Hat's oVirt platform. He also added that this is an area where the developers especially encourage community involvement, so if you want your favorite virtualization technology to be supported in ConVirt, get involved with the project.

Comments (3 posted)

System Applications

Database Software

PostgreSQL Weekly News

The March 29, 2009 edition of the PostgreSQL Weekly News is online with the latest PostgreSQL DBMS articles and resources.

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SQLite release 3.6.12 announced

Version 3.6.12 of the SQLite DBMS has been announced. Changes include some new capabilities, bug fixes and performance improvements.

Comments (none posted)

SQuirreL SQL Client: Version 3.0.1 released (SourceForge)

Version 3.0.1 of SQuirreL SQL Client has been announced, it features bug fixes and a new Korean translation. "SQuirreL SQL Client is a graphical SQL client written in Java that will allow you to view the structure of a JDBC compliant database, browse the data in tables, issue SQL commands etc."

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Device Drivers

Syntek Semicon DC-1125 Driver: Release 2.0.0 (SourceForge)

Version 2.0.0 of Syntek Semicon DC-1125 Driver has been announced. "Linux/Unix driver development for Syntek Semicon USB2.0 Video device DC-1125, like the one that is found in Asus A6K laptops. The device can be recognized by the usb id 174f:a311 and maybe also be a standalone unit (not integrated)."

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Interoperability

Samba 3.2.9 Maintenance Release is available

Maintenance Release 3.2.9 of Samba has been announced. "This is the latest bug fix release for Samba 3.2 and is the version recommended for all production Samba servers running this release series." See the release notes for more information.

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Mail Software

Bogofilter 1.2.0 stable release

Stable version 1.2.0 of Bogofilter, a bayesian spam filter, has been announced. "This release adds 3 new options to force bogofilter to use a specified number of tokens when scoring a message. The options are: --token-count=n --token-count-min=n --token-count-max=n When one or more of these options is specified, bogofilter tries to use the specified number of tokens when computing a message's score."

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Networking Tools

conntrack-tools 0.9.12 released

Version 0.9.12 of conntrack-tools has been announced. "The netfilter project presents another development release of the conntrack-tools that includes a new `-S' option for the command line tool, and a generic infrastructure to allow using different protocols to replicate state-changes, currently unicast UDP and multicast are supported."

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Web Site Development

Midgard2 9.03.0 beta 2 released

Version 9.03.0 beta 2 of Midgard2 has been announced. "The second beta of Midgard2 9.03 is targeted at web framework and desktop developers. It provides a comprehensive set of content repository APIs that can be used to build replicated information applications that share their information using a common storage layer and replication tools."

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Desktop Applications

Audio Applications

Ardour 2.8 released

Version 2.8 of Ardour, a multi-track audio editor, has been announced. "I am pleased to announce the release of Ardour 2.8. As has been previously announced, the 2.X series is now in a state of "feature freeze" so that we can try to concentrate on Ardour 3.0, but as a gesture of thanks to the community for the support during February, I wanted to release this mostly-bugfix version that also comes with a couple of significant features. These include much more reliable VST support on Linux, track/bus templates and, with some important qualifications, AudioUnit state and preset handling."

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Traverso 0.49.1 released

Version 0.49.1 of Traverso has been announced. "Traverso is a cross platform multitrack audio recording and editing suite with a clean and innovative interface targeted for home and professional use. Changes in this release: * New Transport Console * Improvements to the New Project Dialog * AudioClip Selection or Grouping, featuring: Move, Copy, Remove * Fold Sheet or Track: Move all the audioclips in a Track or the entire Sheet right from the mouse cursor without the need to select them first! * Various smaller new features and bug fixes".

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Data Visualization

DISLIN 9.5 released

Version 9.5 of the DISLIN data plotting library has been released. "DISLIN is a high-level and easy to use plotting library for displaying data as curves, bar graphs, pie charts, 3D-colour plots, surfaces, contours and maps. Several output formats are supported such as X11, VGA, PostScript, PDF, CGM, WMF, HPGL, TIFF, GIF, PNG, BMP and SVG."

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Desktop Environments

GNOME Software Announcements

The following new GNOME software has been announced this week:

• Anjuta 2.26.0.1 (bug fixes and translation work)
• Empathy 2.26.0.1 (bug fixes and translation work)
• GBus 0 (initial release)
• GVariant 0 (initial release)
• Libgda 4.0.1 (bug fixes)
• Libvtemm 0.20.2 (new features and bug fixes)
• MonoDevelop 2.0 (new features)
• Peggy 0.02 (unspecified)
• tracker 0.6.92 (new features and bug fixes)
• Vala 0.6.0 (new features and bug fixes)

You can find more new GNOME software releases at gnomefiles.org.

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KDE Software Announcements

The following new KDE software has been announced this week:

• 2ManDVD 0.7.2 (bug fixes)
• 2ManDVD 0.7.3 (bug fixes)
• 2ManDVD 0.7.4 (new features, bug fixes and translation work)
• cb2Bib 1.2.1 (new features and bug fixes)
• copy_path 0.1 (initial release)
• copy_path 0.1.1 (translation work)
• Firewall Builder 3.0.4 (new features and bug fixes)
• fsrunner for KRunner 0.7 (bug fixes)
• Kdenlive Builder Wizard 0.9.9 (new features and bug fixes)
• K Menu Gnome 0.9.2 (new features and documentation work)
• Kopete Antispam Plugin 0.5 (new features and bug fixes)
• KRadio4 4.0.0-rc1 (bug fixes)
• ksynergy 0.5 (new features)
• NetNewsTicker 0.5 (KDE 4 support)
• NetNewsTicker 0.5.1 (bug fix)
• riv 0.8 (bug fixes)
• rkward 0.5.0c (new features and bug fixes)
• Traverso 0.49.1 (new features and bug fixes)
• Wally 2.0.2 (bug fixes and code cleanup)
• VariCAD 2009 1.02 (new features, commercial software)

You can find more new KDE software releases at kde-apps.org.

Comments (none posted)

Xorg Software Announcements

The following new Xorg software has been announced this week:

• xrandr 1.3.0 (bug fixes)

More information can be found on the X.Org Foundation wiki.

Comments (none posted)

Testing Out The Nouveau Driver On Fedora 11 (Phoronix)

Phoronix tries out the Nouveau driver in Fedora 11. Overall, they seemed fairly impressed with its capabilities. "The xf86-video-nv driver is officially maintained by NVIDIA, but it's their half-assed attempt at being open-source friendly. The X.Org driver's code is obfuscated, its 2D support is limited, there is no 3D acceleration at all, and it barely receives new features and support these days. Meanwhile, a group of open-source developers have been reverse-engineering NVIDIA's binary Linux driver to write the Nouveau driver that will offer 2D, 3D, and video acceleration and aims to be feature-complete. The Nouveau project has been around for a few years, but their code is starting to come to maturation with kernel mode-setting and a Gallium3D driver hopefully being stable by year's end."

Comments (27 posted)

Electronics

TTA-Based Codesign Environment 1.0 announced

Version 1.0 of TTA-Based Codesign Environment (TCE) has been announced. "TTA-Based Codesign Environment (TCE) is a toolset for designing application-specific processors (ASP) based on the Transport Triggered Architecture (TTA). TTA is a minimalistic processor architecture template that allows high level of control for the designer to choose the boundary between the hardware and the software. The toolset provides a complete codesign flow from C programs down to synthesizable VHDL and parallel program binaries. Processor customization points include the register files, function units, supported operations, and the interconnection network."

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Fonts and Images

Open Clip Art Library release 0.19 announced

Release 0.19 of Open Clip Art Library has been announced. "Release 0.19 of Open Clip Art Library, containing over 12,000 high quality scalable vector graphics (SVG) files released into the public domain by over a 1000 artists, is now available for download and use. In celebration of this accomplishment, since OCAL's last release happened in 2005, and March being 5th anniversary of the Open Clip Art Library (OCAL), the OCAL community set a goal to achieve 10,000 uploaded pieces of vector graphics."

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Interoperability

Wine 1.1.18 announced

Version 1.1.18 of Wine has been announced. Changes include: "RPC over HTTP support. Improved support for upgrades in MSI. Debug symbols in WineDbg on Mac OS X. Many Direct3D code cleanups. Various bug fixes."

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Multimedia

Elisa Media Center 0.5.34 released

Version 0.5.34 of Elisa Media Center has been announced. "This release fixes a bunch of bugs and introduces cool new features (under the hood) in the widgets system and the styling engine."

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Music Applications

guitarix-0.03.9-1 bugfix release

Version 0.03.9-1 of guitarix, a JACK-based guitar amplifier, has been announced. "This is a bugfix release. fixed bug's : set gain persistent in jconv settings remove compiler flags ( sse + fast-math ) make guitarix_midi_out temporarly".

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Strasheela 0.9.10 released

Version 0.9.10 of Strasheela has been announced. "Strasheela is a highly expressive constraint-based music composition system. Users declaratively state a music theory and the computer generates music which complies with this theory. A theory is formulated as a constraint satisfaction problem (CSP) by a set of rules (constraints) applied to a music representation in which some aspects are expressed by variables (unknowns)."

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Miscellaneous

OmegaT: Stable version 1.8.1 update 3 released (SourceForge)

Version 1.8.1 update 3 of OmegaT has been announced. "OmegaT is a free and open source multiplatform Computer Assisted Translation tool with fuzzy matching, translation memory, keyword search, glossaries, and translation leveraging into updated projects. A new maintenance version of OmegaT 1.8.1 has been released. The focus of this release is on spellchecking, with two bug fixes and one enhancement."

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XMind: 3.0.2 Released (SourceForge)

Version 3.0.2 of XMind has been announced. "Popular brainstorming and mind mapping tool, Eclipse Community Award 2008 winner, often used for capture ideas, knowledge/project management and GTD, supporting fishbones/org-charts/tree charts/spreadsheets, compatible with Freemind/Mindmanager,easy-to-use. Change of Version 3.0.2 New Features: 1. Security 2. New Sheet from Topic 3. Hyperlink in Notes"

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Languages and Tools

C

GCC branches for the 4.4.0 release

The GCC project has created a release branch for 4.4.0, opening up the mainline for new development. This branch has been held up for some time while the Free Software Foundation has pondered changes to the licensing for the GCC runtime libraries. The delay has created some significant unhappiness in the GCC community, some members of which have vocally wondered what the GCC steering committee is for if the FSF is making this kind of decision. The logjam appears to have been cleared, but there has been no word, yet, on any decisions on the licensing issues.

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Caml

Caml Weekly News

The March 31, 2009 edition of the Caml Weekly News is out with new articles about the Caml language.

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Python

Sphinx 0.6.1 and 0.5.2 released

Versions 0.6.1 and 0.5.2 of Sphinx have been announced. "Sphinx is a tool that makes it easy to create intelligent and beautiful documentation for Python projects (or other documents consisting of multiple reStructuredText source files)."

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Python switches to Mercurial

Guido van Rossum has announced that the Python project will be moving to the Mercurial distributed version control system. "It's hard to explain my reasons for choosing -- like most language decisions (especially the difficult ones) it's mostly a matter of gut feelings. One thing I know is that it's better to decide now than to spend another year discussing the pros and cons. All that could be said has been said, pretty much, and my mind is made up."

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Python-URL! - weekly Python news and links

The March 28, 2009 edition of the Python-URL! is online with a new collection of Python article links.

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Tcl/Tk

Tcl-URL! - weekly Tcl news and links

The March 27, 2009 edition of the Tcl-URL! is online with new Tcl/Tk articles and resources.

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XML

pyxser 0.1r announced

Version 0.1r of pyxser has been announced. "pyxser stands for Python XML Serialization, it's Python object serializer that does the job in a standard way. Unlike other serializers, it uses structured document defined in the pyxser DTD, has a FPI (forma public identifier) and the deserialization process run before validating the serialized object document against the pyxser DTD."

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Cross Compilers

Arduino 0015 released

Version 0015 of Arduino, an open-source development system for Atmel AVR microprocessors, is available. The main new feature is support for the new Arduino Mega development board, see the release notes for more information.

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Editors

Emacs 23.0.92 pretest released

Pretest version 23.0.92 of the Emacs editor is out. This is a testing release for what will become Emacs 23.1.

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Page editor: Forrest Cook

Linux in the news

Recommended Reading

Building on Richard Stallman's Greatest Achievement (Linux Journal)

Over at Linux Journal, Glyn Moody looks at efforts to project Richard Stallman's copyright hack (the GPL) into the World Trade Organization (WTO). "The similarities are clear. Both copyright and the WTO have both been instruments of control that seek to limit what people — and peoples — can do in their respective spheres of creation and trade. Both have steadily accreted powers over the years, until they have become hugely problematic for those who wish to see knowledge and products based on knowledge made as widely available as possible. So the idea that Stallman's hack might be applicable is certainly attractive — exciting even."

Comments (3 posted)

Trade Shows and Conferences

Microsoft: Judge us by our deeds on open source (The Register)

The Register covers comments by Microsoft's Robert Youngjohns at the Open Source Business Conference. "Microsoft has made a "tremendous commitment" to systems and file interoperability, according to its head of North American sales and marketing. Robert Youngjohns on Wednesday called interoperability between Widows and Linux and support for open-file formats and open-source languages like PHP a business imperative. He added Microsoft should be judged by its actions with support for PHP, not by its words - presumably statements by senior management on alleged violations of hundreds of Microsoft patents by Linux and open source."

Comments (26 posted)

Companies

Intel Turns Over Its Linux Operating System (NY Times)

The New York Times reports that Intel will be handing control of the Moblin distribution (recently reviewed by LWN) to the Linux Foundation. "Intel will maintain strong control over the software since it employs the top Moblin developers. But that could change over time as outside developers show interest in the software."

Comments (7 posted)

Linux maker a "tempting" takeover target (Reuters)

Reuters reports that Red Hat Inc. is ripe for a corporate acquisition. "Citigroup said Red Hat Inc, which posted strong quarterly results on Wednesday, is a potential takeover target as the Linux software maker's strategy attracts the attention of larger technology firms. Citigroup and RBC Capital raised their price targets on Red Hat, which also forecast full-year results in line with market estimates. "We believe Red Hat is a tempting acquisition target," Citigroup analyst Brent Thill wrote in a note to clients."

Comments (41 posted)

Legal

Microsoft, TomTom Settle Patent Infringement Battle (eWeek)

Microsoft and TomTom have settled their patent dispute as reported by eWeek. TomTom will pay Microsoft an undisclosed amount of money to license the patents, while removing code covered by the FAT patents over the next two years. "According to Microsoft, the agreement includes patent coverage for Microsoft's three file management systems patents provided in a manner that is fully compliant with TomTom's obligations under the General Public License Version 2 (GPLv2). TomTom will remove from its products the functionality related to two file management system patents (the "FAT LFN patents"), which enables efficient naming, organizing, storing and accessing of file data, Microsoft said. TomTom will remove this functionality within two years, and the agreement provides for coverage directly to TomTom's end customers under these patents during that time." While Microsoft and TomTom say this is all GPLv2 compatible, there may be others who disagree.

Comments (17 posted)

TomTom - 'Settled, But Not Over Yet' says SFLC (Groklaw)

Groklaw covers the Software Freedom Law Center's response to the TomTom settlement. From SFLC: "Today's settlement between Microsoft and TomTom ends one phase of the community's response to Microsoft patent aggression, and begins another. On the basis of the information we have, we have no reason to believe that TomTom's settlement agreement with Microsoft violates the license on the kernel, Linux, or any other free software used in its products. The settlement neither implies that Microsoft patents are valid nor that TomTom's products were or are infringing."

Comments (6 posted)

Interviews

From ext3 to ext4: An Interview with Theodore Ts'o (Linux Magazine)

Over at Linux Magazine, Jeff Layton interviews ext4 hacker Ted Ts'o. Layton stays away from the recent ext4 controversy, instead looking at the design goals and future plans for ext4. "One of our primary design goals was that it should be painlessly easy to upgrade from ext3 to ext4. You might not get all of the benefits of ext4 unless you do a backup/reformat/restore of your filesystem, but you would get at least some of the benefits by simply remounting the filesystem using ext4 and enabling some of ext4's features."

Comments (40 posted)

Resources

Music Notation Software for Linux: a Progress Report, Part 1 (Linux Journal)

Dave Phillips looks at the status of the five most active notation software projects. "The essential requirements for all music notation programs include various score layout functions, data entry methods, music symbol palettes, audio output support modes and options for printing the finished score. Basic programs may include only a limited subset of the possible features, while more professional software offers more features for greater control over the details of a work. Of course, with greater control comes greater complexity. The designers of music notation programs work hard to balance ease of operation with the proliferation of features."

Comments (4 posted)

Reviews

8TB NAS runs Linux (LinuxDevices)

LinuxDevices takes a look at Seagate's soon to be released NAS device. "Seagate is readying a four-bay network-attached storage device for small businesses that runs embedded Linux and stores up to 8TB. The hot-swappable BlackArmor NAS 440 offers an iTunes server and DLNA-compliant media server, RAID 0/1/5/10, dual gigabit Ethernet ports, and four USB ports, says Seagate. With the BlackArmor NAS 440, Seagate has launched its first homegrown, small business NAS device, re-launching a BlackArmor brand that it picked up when it acquired Maxtor in 2006."

Comments (11 posted)

Miscellaneous

A New Memory Tool for the Web (Ben Galbraith's Blog)

Ben Galbraith is Mozilla's Co-Director of Developer Tools. In this blog post he ponders various gaps in the tool-chain with regard to memory tools. "To be clear, most web pages and web applications don't push the browser's memory limitations enough to cause performance problems related to either of the scenarios above. As stated at the outset, this blog entry is about those web applications that need to treat the browser as a high-performance run-time, which in the context of this entry means that they have much-larger-than-average memory requirements." (Found on Linux Journal)

Comments (none posted)

Page editor: Forrest Cook

Announcements

Non-Commercial announcements

A revised GCC runtime library exception

The Free Software Foundation has posted a revised version of the new GCC runtime library exception. There's no description of the changes, but the new text is short and easy to read. Essentially, it seems to specifically equate Java virtual machine code with human-readable languages, meaning that Java byte code can be processed through GCC and still link against the runtime library.

Comments (8 posted)

Newest member of the Linux Foundation - credativ

The Linux Foundation has announced credativ as its newest member. "credativ, an independent consulting and services company focused on free software and open standards, will participate in advancing the Linux Standard Base (LSB), which establishes common standards across the different Linux distributions. Additionally, as one of Europe's largest employers of Debian developers, credativ has a particular interest in encouraging collaboration focused around Debian development."

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Commercial announcements

Rackable Systems acquires SGI

SGI has announced that it has been acquired by Rackable Systems Inc. The purchase price is "approximately $25 million."

Comments (23 posted)

New Books

Beautiful Teams - New from O'Reilly

O'Reilly has published the book Beautiful Teams by Andrew Stellman and Jennifer Greene.

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Java SOA Cookbook--New from O'Reilly

O'Reilly has published the book Java SOA Cookbook by Eben Hewitt.

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Education and Certification

"Advanced Scientific Programming in Python" Summer School in Berlin

The Advanced Scientific Programming in Python Summer School will be held in Berlin, Germany from August 31 - September 4, 2009. "Many scientists spend much of their time writing, debugging, and maintaining software. But while techniques for doing this efficiently have been developed, only few scientists actually use them. As a result, they spend far too much time writing deficient code and reinventing the wheel instead of doing research. In this course we present a selection of advanced programming techniques with theoretical lectures and practical exercises tailored to the needs of the programming scientist."

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Perl Fundamentals DVD out (use Perl)

use Perl has announced the availability of a Perl educational DVD. "Peter Scott has just created a learning Perl DVD, published by Addison Wesley. 4+ hours of Perl instruction on screencast with video of the author introducing each lesson. This is an introduction to Perl for the student who learns by example and prefers a visual and/or auditory style."

Comments (none posted)

Calls for Presentations

DeepSec 2009 - Call for Papers is open

A call for papers has gone out for DeepSec 2009. "The DeepSec organisation is happy to announce the Call for Papers for the next conference in November 2009. The conference will take place at the Imperial Riding School Renaissance Hotel in Vienna, Austria." Submissions are due by July 15.

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FOSS.IN 2009 announcement and call for participation

FOSS.IN 2009 has been announced. "FOSS.IN/2009 will be held on December 1-5, 2009 (Tuesday through Saturday) at Bangalore's largest and most modern conference venue - the NIMHANS Convention Centre." The first call for participation has gone out for the event.

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Upcoming Events

EuroDjangoCon 09 registration is open

EuroDjangoCon registration is open. "Just to let you know you can still register for EuroDjangoCon '09. The other levels of prices were scrapped and instead we're just going with the early bird rates. It will be in Prague on May 4th - 6th (conference days) and 7th - 8th (sprint days). The venue has changed to the Iris Congress Hotel and the conference is now single track."

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Linux Plumbers Conference 2009 registration opens

Registration for the 2009 Linux Plumbers Conference - September 23-25, Portland - is open. "For those new to the conference, the Linux Plumbers Conference was created to bring together key developers involved in Linux plumbing - the 'Linux plumbers' - and give them an opportunity to discuss problems face-to-face, both within subsystems and across subsystems."

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Events: April 9, 2009 to June 8, 2009

The following event listing is taken from the LWN.net Calendar.

Date(s)	Event	Location
April 8 April 10	Linux Foundation Collaboration Summit	San Francisco, CA, USA
April 14	OpenClinica European Summit	Brussels, Belgium
April 15	Linuxwochen Österreich - Krems	Krems, Austria
April 16 April 17	Nordic Perl Workshop 2009	Oslo, Norway
April 16 April 18	Linuxwochen Austria - Wien	Wien, Austria
April 16 April 19	Linux Audio Conference 2009	Parma, Italy
April 20 April 23	MySQL Conference and Expo	Santa Clara, CA, USA
April 20 April 24	samba eXPerience 2009	Göttingen, Germany
April 20 April 24	Perl Bootcamp at the Big Nerd Ranch	Atlanta, GA, USA
April 20 April 24	Cloud Slam '09	Online, Online
April 22 April 25	ACCU 2009	Oxford, United Kingdom
April 23	Linuxwochen Austria - Linz	Linz, Austria
April 23 April 24	European Licensing and Legal Workshop for Free Software	Amsterdam, The Netherlands
April 23 April 26	Liwoli 2009	Linz, Austria
April 25	Linuxwochen Austria - Graz	Graz, Austria
April 25	Festival Latinoamericano instalación de Software libre	All Latin America, All Latin America
April 25	Grazer Linux Tage 2009	Graz, Austria
April 25 April 26	LinuxFest Northwest 2009 10th Anniversary	Bellingham, Washington, USA
April 25 May 1	Ruby & Ruby on Rails Bootcamp	Atlanta, Georgia, USA
April 27	OSDM 2009	Bangkok, Thailand
May 4 May 6	EuroDjangoCon 2009	Prague, Czech Republic
May 4 May 6	SYSTOR 2009---The Israeli Experimental Systems Conference	Haifa, Israel
May 4 May 7	RailsConf 2009	Las Vegas, NV, USA
May 4 May 8	JavaScript/Ajax Bootcamp at the Big Nerd Ranch	Atlanta, Georgia, USA
May 5	Linuxwochen Austria - Salzburg	Salzburg, Austria
May 6 May 8	Embedded Linux training	Maynard, USA
May 6 May 9	Libre Graphics Meeting 2009	Montreal, Quebec, Canada
May 7	NLUUG spring conference	Ede, The Netherlands
May 8 May 9	Linuxwochen Austria - Eisenstadt	Eisenstadt, Austria
May 8 May 9	Erlanger Firebird Conference 2009	Erlangen-Nürnberg, Germany
May 8 May 10	PyCon Italy 2009	Florence, Italy
May 11	The Free! Summit	San Mateo, CA, USA
May 13 May 15	FOSSLC Summercamp 2009	Ottawa, Ontario, Canada
May 15	Firebird Developers Day - Brazil	Piracicaba, Brazil
May 15 May 16	CONFidence 2009	Krakow, Poland
May 16 May 17	YAPC::Russia 2009	Moscow, Russia
May 18 May 19	Cloud Summit 2009	Las Vegas, NV, USA
May 19	Workshop on Software Engineering for Secure Systems	Vancouver, Canada
May 19 May 21	Where 2.0 Conference	San Jose, CA, USA
May 19 May 22	PGCon PostgreSQL Conference	Ottawa, Canada
May 19 May 22	php|tek 2009	Chicago, IL, USA
May 19 May 22	SEaCURE.it	Villasimius, Italy
May 21	7th WhyFLOSS Conference Madrid 09	Madrid, Spain
May 22 May 23	eLiberatica - The Benefits of Open Source and Free Technologies	Bucharest, Romania
May 23 May 24	LayerOne Security Conference	Anaheim, CA, USA
May 25 May 29	Ubuntu Developers Summit - Karmic Koala	Barcelona, Spain
May 27 May 28	EUSecWest 2009	London, UK
May 28	Canberra LUG Monthly meeting - May 2009	Canberra, Australia
May 29 May 31	Mozilla Maemo Mer Danish Weekend	Copenhagen, Denmark
May 31 June 3	Techno Security 2009	Myrtle Beach, SC, USA
June 1 June 5	Python Bootcamp with Dave Beazley	Atlanta, GA, USA
June 2 June 4	SOA in Healthcare Conference	Chicago, IL, USA
June 3 June 4	Nordic Meet on Nagios 2009	Stockholm, Sweden
June 3 June 5	LinuxDays 2009	Geneva, Switzerland
June 6	PgDay Junín 2009	Buenos Aires, Argentina

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Audio and Video programs

FSF releases audio recording of LibrePlanet conference

Audio recordings are available for the LibrePlanet conference. "The Free Software Foundation (FSF) today released the complete audio recordings from the first day of the LibrePlanet GNU/Linux conference, held on March 21, 2009, in Cambridge, MA. The recordings include a talk given by Samba's Jeremy Allison on Microsoft and its relationship with the free software community, and Gnash developer Rob Savoye announcing the Cygnal project -- a rich media server with features roughly compatible with the Flash Media Server. Two members of the autonomo.us group, Evan Prodromou and FSF director Mako Hill, spoke about efforts to engineer for free network services and the successful launch of the micro-blogging service identi.ca."

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