More DTrace envy [LWN.net]

More DTrace envy

Posted Jul 3, 2008 3:40 UTC (Thu) by flewellyn (subscriber, #5047)
Parent article: More DTrace envy

It's frustrating that Bryan Cantrell apparently reacts to all mentions of license issues as "I
want to talk about technology, not law, legal issues are unimportant".

Well, no, they're not.  If they were, that'd be great, but as it happens, we have to care
about under what terms we use the code that we use, and if the licenses aren't compatible, we
can't use it.

He goes on and on about how foolish the SystemTap people are for trying to reimplement DTrace
when DTrace already exists, while refusing to even discuss the SOLE reason why they saw the
need to bother!

to post comments

More DTrace envy

Posted Jul 3, 2008 5:54 UTC (Thu) by bcantrill (guest, #31087) [Link] (73 responses)

I didn't say that the issues are unimportant, I said that I didn't want to discuss them in the
comments section of my blog (which I don't).  I also happen to think that (1) the licensing
issues are largely a smokescreen for good 'ole NIH in the Linux community and (2) the law
(that is, the case law) in the domain of software licensing is so ill-defined that one can
often conclude what one wishes to conclude.  Take these two together, and you have a plague of
amateur legal opinions, contorted to justify rampant, metastasized NIH -- and I personally
want no part of it.

More DTrace envy

Posted Jul 3, 2008 7:48 UTC (Thu) by k8to (guest, #15413) [Link]

A Sun developer accusing the Linux community of NIH. Great.

More DTrace envy

Posted Jul 3, 2008 8:05 UTC (Thu) by flewellyn (subscriber, #5047) [Link] (67 responses)

Eben Moglen is not an amateur.  And he vets the FSF's legal opinions on license compatibility,
so...if they say it's not compatible, it probably isn't.

As for NIH, well, no, Linux has often adopted ideas from other systems.

More DTrace envy

Posted Jul 3, 2008 8:51 UTC (Thu) by paulj (subscriber, #341) [Link] (66 responses)

Licences being incompatible is a moot, philosophical matter (least until the *AA succeed in
making copyright infringment a criminal matter) if no one thinks the infringment matters. Who
exactly is going to sue if someone distributes a DTrace modified kernel? Sun would have no
standing, as the CDDL seems to allow combining with GPL works. 

So it'd have to be a Linux kernel contributor, sueing someone for distributing free software
derived from free software.

More DTrace envy

Posted Jul 3, 2008 9:28 UTC (Thu) by mjw (subscriber, #16740) [Link] (25 responses)

But it isn't a "moot, philosophical matter". As one of the people who worked for Sun on the
CDDL said the license was explicitly designed to be GPL incompatible on request of the
engineers: http://en.wikipedia.org/wiki/CDDL#cite_note-5

It is simple to make this matter really moot if Sun would want to. All they have to do is
change the CDDL so that there is an explicit permission to distribute a larger combined work
under terms compatible with the GPL.

Since there are records of the incompatibility being deliberate it isn't even just a legal
matter. It would actually be rude and impolite to go against the wishes of the copyright
holder at this time. You do have to respect their wishes even if you could find some legal
loophole to go against it.

But if they really change their minds and put that in writing by updating the CDDL that would
be wonderful of course. Lets hope they mean it and indeed make this a legally mood matter for
real. And then we can all happily work together without having to have any doubts about it.

More DTrace envy

Posted Jul 3, 2008 12:10 UTC (Thu) by paulj (subscriber, #341) [Link] (24 responses)

Look, the CDDL appears to be absolutely fine with copyright holders of GPL works incorporating
CDDL software and distributing it. All the GPL copyright holders have to do is promise not to
sue themselves or others for it. Pretty simple. (Consult your own counsel, of course!).

Essentially, you're complaining that Sun released free-software under a licence not quite to
your liking. Further, given that Sun legal had some involvement in the GPLv3 process, it's
possible that even if Sun had chosen the GPL, Sun'd have chosen v3 (course, v3 took another
few years to be finalised..), and people would still be complaining.

Further, in good humour, you're speculating yourself toward conspiracy-theory kook land. Read
what Danese said, she said "partially because". It's therefore entirely reasonable to think
there were other factors involved. E.g. one of the major differences between the CDDL and the
GPLv2 concerns patent rights and Sun is subject to patent infringment suits on a
not-infrequent basis. It seems reasonable to put and two and two together and speculate that
Suns' lawyers really wanted a licence with some kind of patent cross-licensing language. I.e.
it's possible GPL-licensing simply would not have been acceptable, regardless of what you take
from Danese's comment.

NB: I work for Sun, but I was no more privy to the "which licence for opensolaris?"
discussions than you were (indeed, they would have predated my employment largely ;) ).

More DTrace envy

Posted Jul 3, 2008 12:45 UTC (Thu) by mjw (subscriber, #16740) [Link] (23 responses)

No, I am not complaining about which free software licenses Sun choose. I am happy they
release software under a free license. And I hope they will do more of it. However pretending
that legal uncertainty and explicitly distributing source code under GPL-incompatible terms
aren't a (the) major issue, while claiming to want wider adoption of that code base under
GNU/Linux and suggesting it isn't adopted because of NIH is just silly.

I have worked on several occasions with Sun, and I have spoken on several occasions to Danese
and other people at Sun about free software, CDDL, GPL,  communities and legal issues to know
they really understand that the legal uncertainty around the CDDL is the only issue preventing
adoption of the technology on a wider scale in GNU/Linux.

As GNU Classpath maintainer I have been more than impressed with how Sun handled Java the last
couple of years. The GNU and Sun java communities happily work together now (after 15 years of
separation) exactly because Sun made sure to do the right thing legally to ensure the widest
possible adoption and cooperation with the existing libre-java communities. I have only praise
for how that was handled. And that is really the reason I am so disappointed about the mess
they made with dtrace/cddl preventing cooperation and adoption on a wider scale, while
claiming to want cooperation that is impossible to achieve because of these messy legal
issues.

More DTrace envy

Posted Jul 3, 2008 14:13 UTC (Thu) by paulj (subscriber, #341) [Link] (9 responses)

Well, Danese left Sun quite a few years ago. Also, be sure to read Simon Phipps response
(linked from the Wiki article you linked to).

I accept there are differences and difficulties. However, it is Suns' prerogative to define
how the software it created is to be derived from. Again though, Suns' licence does *not*
(AIUI+IANAL) prevent other OSes from re-using that code - not even Linux (even if it does
require collective action from Linux copyright holders). Reading the tea-leaves to find
evidence of Suns' "evil" intentions is however not at all productive, no matter whose side
you're on. Then projecting a moral duty of having to respect these *divined intentions* is,
again with all due respect, not very sensible.

If there are problems on some side, then the only way understanding can increase and so
solutions (if any) are ever be found is through dialogue.

More DTrace envy

Posted Jul 3, 2008 14:29 UTC (Thu) by drag (guest, #31333) [Link] (8 responses)

You have it backwards.

It's not that the GPL is incompatible with the CDDL... The CDDL was designed, specifically, to
be incompatible with the GPL. Even if all the Linux kernel developers decided that CDDL was
acceptable, then it still wouldn't matter. Sun _doesn't_want_it's_code_in_the_linux_kernel_.

That's it. They don't want Dtrace to be in Linux. They don't want ZFS in Linux. Get it? They
did it on purpose. So all the philosophical or political are the arguments that are MOOT. Sun
made sure of that. Sun says their code isn't going into Linux, then their code isn't going in.
There is absolutely no question about this.

Your the only one mentioning 'evil' here or anything like that. You can see their intentions
very clearly written in between the lines in the CDDL license even if you don't believe
Danese. All the legal ramifications have already been worked out years in advanced for
Mozilla-like licenses and Sun could of easily made it compatible with Linux, but they chose
not to do that. EASILY. No question about that at all.

Most everybody, unless they are loonies, is happy that Sun has their code under a open
license, even if it's intentionally incompatible with the (pre-existing and very well
established) GPL license.

They may change their mind in the future and make the license compatible, but until then it's
not going in.

You see, that's how you know Sun wouldn't mind having it's code in Linux. If they made the
license compatible then you'd know it was ok. Everything else is handwaving.

More DTrace envy

Posted Jul 3, 2008 14:55 UTC (Thu) by paulj (subscriber, #341) [Link] (6 responses)

Even if all the Linux kernel developers decided that CDDL was acceptable, then it still wouldn't matter. Sun _doesn't_want_it's_code_in_the_linux_kernel_.

Sun has published its code under the CDDL. It's a free software licence that's quite permissive. At least one other OS (if not two) has incorporated code (the crown jewels no less) from Solaris, by way of the CDDL licence. Take that + whatever statements you want from its officers that seem interpretive or estopping and ask your lawyer for an opinion.

What you feel Sun wants, or what you think the CDDL was designed specifically for, is amazingly speculative at best and largely irrelevant to anyone considering porting CDDL code.

More DTrace envy

Posted Jul 3, 2008 19:21 UTC (Thu) by bronson (subscriber, #4806) [Link]

> what you think the CDDL was designed specifically for, is ... largely irrelevant to anyone
considering porting CDDL code.

Do you seriously believe this?

Do you agree that the CDDL is incompatible with the GPLv2?  If so, then don't you think that
someone considering porting CDDL code to a GPL project had better consider whether his actions
are even legal?  That hardly sounds irrelevant!

If there's estoppel that would allow the CDDL to be used with the GPL, do you suppose you
share a link?  Every communication from Sun that I've seen has very specifically avoided this.

If Sun actually does want its CDDL code to be incorporated into GPLv2 projects, it would take
only tiny changes.  Since the GPL is older and more popular (http://freshmeat.net/stats/), one
would expect that Sun carefully considered researched GPL compatibility.  Even if the
incompatibility is an honest mistake, then why doesn't Sun make the tiny changes required now
to rectify the situation?

More DTrace envy

Posted Jul 5, 2008 19:13 UTC (Sat) by drag (guest, #31333) [Link] (4 responses)

> Sun has published its code under the CDDL. It's a free software licence that's quite
permissive. At least one other OS (if not two) has incorporated code (the crown jewels no
less) from Solaris, by way of the CDDL licence. Take that + whatever statements you want from
its officers that seem interpretive or estopping and ask your lawyer for an opinion.

They don't care if FreeBSD or OS X adopts ZFS or Dtrace because those operating systems are
irrelevant and are not competitive. Sun doesn't care if OS X adopts ZFS because they won't do
anything interesting with it. At most it will make OS X users feel better because they can
finally have a file system that doesn't suck worse then Vfat.

If Sun has it's software adopted by the Linux folks then they lose control over it. They will
improve it and incorporate it into Linux and it will be yet another reason why nobody has a
reason to choose Solaris over Linux.

Linux is now the dominate Unix system out there. Sun wants to maintain control over their
'ip'. They've done that with most everything they've released. They are learning to let go,
but it's slow coming.

Then explain to me why the hell Sun has not extended it's patent protections (use our IP and
we won't sue you) only to the users of CDDL-licensed code and not open source programmers and
users in general? Other people have done this (Redhat, Novell (not talking about the MS-Novell
agreement, but previous things they've done), it's certainly possible.

> What you feel Sun wants, or what you think the CDDL was designed specifically for, is
amazingly speculative at best and largely irrelevant to anyone considering porting CDDL code.

_read_the_license_. The license expresses intent. That's the point of it.

70%-90% of open source software used in a commercial environment is going to be licensed GPL.
Your telling me that Sun made CDDL problematic to be used in the majority of popular open
source software by ACCIDENT?

All they had to do was make a exception. They can still do it now. Mozilla did it.

They took and copied a license that everybody, including the original authors (Mozilla),
realizes is problematic when combined with other open source software and Sun didn't realize
it?

More DTrace envy

Posted Jul 6, 2008 11:10 UTC (Sun) by paulj (subscriber, #341) [Link] (3 responses)

You're the second person to have misread my (I thought fairly clear) comment, so I guess I
need to reply and clarift: I specifically said that *your* opinion of Suns' motivations in
choosing the CDDL was largely irrelevant (not least because motivations, even when generally
acknowledged, aren't that relevant).

Next (sorry to restate, but its important to the coherence of this post) you have been given
several reasonable, practical and good reasons why the GPLv2 would not have been acceptable to
Sun, regardless of Suns' motivations towards Linux, namely:

- Sun did not want to dictate to ISVs that they must GPL their code. (This one you have heard
directly from Bryan)

- Sun does not want licence-forking (to cover any rebuttal to the previous point of "so use
LGPL", as the LGPL can be converted to GPL, and ignoring the fact that the LGPL is far from
pretty)

- The GPLv2 is out of date with regard to patents. That Sun added patent cross-licensing+MAD
terms to CDDL suggests this may have been a factor. (Why it applies only to CDDL? I've no
idea.. I suspect there may be legal, technical difficulties in drafting the language to have
many other licences - particularly with regard to the 'MAD' aspect of the CDDL patent
language. Can you provide a pointer to the grants you refer to? Be interesting to read).

Next, ignoring the above and if we accept your argument: Exactly how did you develop this
massive sense of entitlement that you think it is your automatic right to Suns' code on
licensing terms favourable to your chosen OS? I'm a Free Software Foundation supporter and I
always understood that the ethical reasoning for companies to choose the free software was out
of respect for their *users*...

Finally, can you tell me with a straight face that had Sun chosen the GPL but it had chosen
the GPLv3 (imagining the GPLv3 had existed), that you'd then not be complaining here today
about Suns' choice of licence? Even though it too is incompatible with Linux to the *same
extent* as the CDDL is (namely: it'd require linux copyright holders to agree to update the
Linux not-quite-GPLv2 licence)?

More DTrace envy

Posted Jul 7, 2008 2:39 UTC (Mon) by clump (subscriber, #27801) [Link] (2 responses)

Forgive me, but the argument appears to be about whether CDDL-licensed can be used in Linux, or specifically GPL-licensed works. You started by saying:

Licences being incompatible is a moot, philosophical matter...

and:

Look, the CDDL appears to be absolutely fine with copyright holders of GPL works incorporating CDDL software and distributing it.

However this next quote is curious given your views:

Exactly how did you develop this massive sense of entitlement that you think it is your automatic right to Suns' code on licensing terms favourable to your chosen OS?

With the last quote, it looks like you agree that the CDDL and GPL aren't compatible. You object to people arguing *why* Sun chose the license. Fine. But you very much appear to give legitimacy to those not wishing to mix the licenses together.

More DTrace envy

Posted Jul 7, 2008 9:48 UTC (Mon) by paulj (subscriber, #341) [Link] (1 responses)

You have deliberately omitted the statements immediately following the ones you've quoted
which qualify those quotes. The first quote is particularly out of context, as the qualifying
statement is in the same sentence: "... if no one thinks the infringment matters.".

That's quite trollsome behaviour, something I would not have expected from an LWN subscriber.

More DTrace envy

Posted Jul 7, 2008 17:22 UTC (Mon) by clump (subscriber, #27801) [Link]

Ignoring your attacks, myself and some others here obviously think infringement matters.
That's kind of the point... It's also ironic that you've gone out of your way to condemn others
for thinking they know why Sun chooses the licenses it does, yet you consider it a deliberate
attempt to troll when someone points out what appears to be inconsistency in your logic.

By all means, disagree with my point if I am wrong but don't pretend you're taking the high
road.

More DTrace envy

Posted Jul 3, 2008 15:41 UTC (Thu) by zooko (guest, #2589) [Link]

Be careful using the notion of "Sun" as a person which can have intentions and plans and so
forth.  Even though the people who chose CDDL did so deliberately in order to avoid their
technologies being added into Linux (according to Danese Cooper's public comments and other
private communications that I've had with other Sun employees), that doesn't mean that Bryan
Cantrill so chose, or even that he is aware of or believes that it was so chosen.

Anyway, Bryan Cantrill's knowledge, opinions, and intentions are necessarily different than
those of other Sun employees, and neither is he wholly responsible for what the company does
nor is the company wholly responsible for what he does.

There is a sense in which companies cannot actually have intentions.  Fortunately, in our
society we allow them to enter into binding agreements, such as by publishing their software
under an open source licence, so that we no longer have to form a mental model of the
company's intention in order to know what we can do with their source code.

P.S.  I'm glad that free and open Solaris exists, as well as other free and open operating
systems such as the BSD's and apparently eventually Symbian.  If every computer in the world
ran Linux, we would all be poorer for it -- monoculture leads to stagnation and fragility.
Diversity and competition is the fount of creativity and excellence.

More DTrace envy

Posted Jul 3, 2008 14:33 UTC (Thu) by bcantrill (guest, #31087) [Link] (12 responses)

However pretending that legal uncertainty and explicitly distributing source code under GPL-incompatible terms aren't a (the) major issue, while claiming to want wider adoption of that code base under GNU/Linux and suggesting it isn't adopted because of NIH is just silly.

And now we have arrived at the central disconnect between us and the Linux community: we did not open source Solaris to get "wider adoption of that code base under GNU/Linux"; we open sourced Solaris because of our own business objectives, some of which I have previously described. Contrary to the beliefs of some in the GNU/Linux community, GNU/Linux and GPL are not the beginning and end of open source, and as we have explained, GPLv2 was not acceptable to us because we could not dictate licensing terms to in-kernel software writers, many of whom are 3rd parties who either will not or cannot relicense. Having an open source license that allowed for different license terms (including proprietary ones) was and is a constraint; allowing our technology to be ported to other operating systems was of secondary concern.

So there you have it: while we would welcome DTrace in Linux (and we will help and are helping those that would port it), it's not something we covet. If you want it, take it. If you don't, fine -- but know that many of your users would like to see you embrace the technology, and happen to care much more about solving their business problems than about legal arguments about why it's "impossible"...

More DTrace envy

Posted Jul 3, 2008 16:32 UTC (Thu) by willy (subscriber, #9762) [Link] (8 responses)

Brian, if you want DTrace to be part of Linux, just dual-license it.  You can release your
code under "CDDL or GPL" and then it can happily become part of Linux.  I, for one, would
welcome that.

More DTrace envy

Posted Jul 3, 2008 17:30 UTC (Thu) by bcantrill (guest, #31087) [Link] (7 responses)

Brian, if you want DTrace to be part of Linux, just dual-license it. You can release your code under "CDDL or GPL" and then it can happily become part of Linux. I, for one, would welcome that.

Dual licensing is something that the OpenSolaris community is very strongly against -- in part because dual licensing creates the possibility of a license-based fork. (Which given the enmity towards both Sun and the CDDL among many in the Linux camp, seems to be a very real possibility.) And again: we don't "want" DTrace to be a part of Linux -- it's up to the Linux community to want that, just as it was up to the FreeBSD, MacOS X and QNX developer communities to want it...

More DTrace envy

Posted Jul 3, 2008 19:33 UTC (Thu) by bronson (subscriber, #4806) [Link] (2 responses)

FreeBSD, MacOS X, QNX...  So all we have to do is relicense the Linux kernel under BSD?  Well,
why didn't you say so!  That sounds so easy!

Perhaps you're interpreting a specific licensing incompatibility as a lack of desire from the
Linux community?  I can assure you, the community as a whole really does want to integrate
DTrace.  A lot!  TONS.  It would happen in a matter of weeks if only the licenses allowed it
to be possible.

More DTrace envy

Posted Jul 3, 2008 20:00 UTC (Thu) by bcantrill (guest, #31087) [Link] (1 responses)

Now there's some big talk!  Do you have any idea of the technical details involved in this, or
are you one of the ESR groupies who believes that given "enough eyeballs" pixies and fairies
magically solve all problems?  I can assure you from working with Paul that the Linux
idiosyncrasies are making the DTrace port rougher going than most -- and porting DTrace is a
deeply technical endeavor on the best of days.  So it would not show up in a "matter of
weeks", even if it were GPLv2 and Torvalds himself were doing the port.  (Sacrilege, I know.)

More DTrace envy

Posted Jul 3, 2008 21:16 UTC (Thu) by bronson (subscriber, #4806) [Link]

I was careless and I'm sure you're right.  What I *should* have said is, "lots of Linux devs
would spend a lot of their time incorporating DTrace, if only the licenses allowed it."

But my point remains: you seem to be interpreting license problems as a lack of desire.  The
desire is there, no question!  If the licensing problems could just be fixed somehow, I'm
confident the Linux camp would devote amazing hours to DTrace.

As it is, they have to devote amazing hours to replicating DTrace.  :(

More DTrace envy

Posted Jul 3, 2008 19:42 UTC (Thu) by k8to (guest, #15413) [Link]

Wow, more disingenouousness.  I'm impressed.

More DTrace envy

Posted Jul 4, 2008 9:33 UTC (Fri) by dark (guest, #8483) [Link]

Dual licensing is something that the OpenSolaris community is very strongly against -- in part because dual licensing creates the possibility of a license-based fork.

No, it doesn't. Even if there were a GPL-only fork, SUN could simply use the GPL code in its CDDL products, under the "legal arguments don't matter" approach that you advocate. After all, they are both free software licenses.

Or does the shoe pinch on the other foot?

More DTrace envy

Posted Jul 6, 2008 2:13 UTC (Sun) by dirtyepic (guest, #30178) [Link]

Dual licensing is something that the OpenSolaris community is very strongly against -- in part because dual licensing creates the possibility of a license-based fork.

How can you fear a licensed-based fork when incompatible licenses are a "moot, philosophical matter"?

fork fears could be worked out

Posted Jul 7, 2008 18:09 UTC (Mon) by JoeBuck (subscriber, #2330) [Link]

The issue of a fork could be worked out. Sun count agree to dual-license DTrace, and Linus and the other kernel developers could agree to dual-license all improvements to that code that are accepted into the internal tree. This would neutralize any legitimate fears on the part of OpenSolaris developers that the Linux side would take and not give. It might require some re-architecting to separate out common code, from code that is Solaris-specific or Linux-specific. But Sun would gain a larger developer community to help improve the code.

More DTrace envy

Posted Jul 3, 2008 16:43 UTC (Thu) by nhippi (subscriber, #34640) [Link]

> know that many of your users would like to see you embrace the technology, and happen to
care much more about solving their business problems than about legal arguments about why it's
"impossible"

It works the other way around too. Many people would like to use solaris but can't since the
drivers are missing and care more about solving their business problems than legal arguments
why it's "impossible" to solaris to copy those drivers from Linux to solaris.

And to remind you, this problem was not created by Linux community or GPLv2, but by SUN. The
more paranoid side of community believes the problem was created on purpose.

In a hindsight it might seem it's not a problem to sun's customers, since Sun is surely
capable of rewriting (who was it again calling NiH?) all drivers needed to run the Sun servers
being sold, even if there already is a working GPLv2 driver. However, even Sun systems have
these USB/PCI-express expansion slots, where many people would like to attach interesting
hardware...

More DTrace envy

Posted Jul 7, 2008 10:26 UTC (Mon) by arafel (subscriber, #18557) [Link]

>but know that many of your users would like to see you embrace the 
>technology, and happen to care much more about solving their business 
>problems than about legal arguments about why it's "impossible"...

I'm sure it wasn't what you intended, but the tone of that comment makes it appear (at least
to me) like you're suggesting legal restrictions don't matter. Could you clarify that
slightly...?

To be honest, I'm having some difficulty with your post altogether. The suggestion that the
Linux developers are being deliberately obtuse in not integrating software which legally they
cannot integrate is, um, curious. Or do Sun not bother with such restrictions? ;-)

(Joking, I'm joking...)

choosing whether to allow dtrace integration with gnu/linux

Posted Jul 9, 2008 20:09 UTC (Wed) by mjw (subscriber, #16740) [Link]

we would welcome DTrace in Linux

You seem to flipflop a bit on the that point :) Certainly you don't have any obligation to make it possible by removing the legal uncertainty around the current dtrace CDDL license and how it interacts with the GPL. But as you can see from the discussions whenever you claim that dtrace would be better than sliced bread for integration into GNU/Linux systems (or at least so much better than what is currently only half-integrated, like Systemtap and friends), this legal uncertainty is the only real reason dtrace isn't even a choice in providing something better.

You keep claiming that there is no way to resolve the legal ambiguity without harming the OpenSolaris community. If true, then indeed dtrace will never be a choice for GNU/Linux as a whole. I am not convinced that is really impossible though. Pure GPL or LGPL is too copyleft for your taste. That can be rectified by adding an explicit exception for your use cases. This is what Sun did for OpenJDK which had the same constraints, there still was proprietary code that needed to be linked to. The other way is of course dual-licensing. Which you say you don't want because of the fear of forks. Which of course is true and could happen in theory. But Sun also did this for projects like Glassfish and NetBeans which were originally CDDL only, but are now dual licensed CDDL/GPL. So it seems at least Sun legal thinks this is an appropriate way to both protect a code base and make it more compatible with other communities. The suggestion from others to only do this if you can get some prominent figures in the community to say that they support the dual licensing and condemn single-license forks is a good suggestion. Richard Stallman did that explicitly when Mozilla dual licensed their code (see the legal FAQ Q/A 11 till 13).

Now I am not claiming that systemtap, lttng, tracepoints, markers, kprobes, utrace, uprobes, ftrace, etc. did everything so much better than dtrace. In fact you could see all the trouble they needed to go through to make their implementations as generic as possible before being (partially) accepted and integrated into mainline as an indication of the hard work that still is still ahead for dtrace to get integrated and accepted even if the legalities were cleared up. But they did make it so that eventually their code could be integrated legally into the mainline kernel and intermingled with each other to ultimately provide better, safe and powerful frameworks for observability under GNU/Linux.

It will be interesting to see how these projects morph GNU/Linux into a fully observable system such as solaris has through dtrace. It would be even more interesting if you could lift the legal uncertainties around dtrace and make it a true contender in this coopetive race towards full observability. It is your choice to make though.

More DTrace envy

Posted Jul 3, 2008 9:34 UTC (Thu) by mjg59 (subscriber, #23239) [Link] (38 responses)

Pedantically, it's a Linux kernel copyright holder rather than a Linux kernel contributor.
Some portions of code have been lifted from other projects, and some portions of code have
been signed away to other organisations. But to the extent that I think it's unlikely that
anyone would sue, I agree. "Unlikely" probably isn't good enough for the large companies that
could be potential targets, though, and as a result it's a practical matter as well as a
philosophical one.

More DTrace envy

Posted Jul 3, 2008 12:26 UTC (Thu) by paulj (subscriber, #341) [Link] (37 responses)

"Unlikely" probably isn't good enough for the large companies that could be potential targets, though, and as a result it's a practical matter as well as a philosophical one.

You're talking about legal risk, and you can't eliminate it. All companies must live with it, companies shipping software particularly so. Your legal department should be well-versed in considering legal risks and you really should talk to them about it.

I didn't realise there'd be such a big risk of Linux kernel contributors and/or copyright holders suing *each other*. Sounds like a fun community..

More DTrace envy

Posted Jul 3, 2008 12:41 UTC (Thu) by mjg59 (subscriber, #23239) [Link] (35 responses)

As an example, SCO own copyright to various pieces of Linux. Microsoft could buy one of the
small companies that owns various files. Stepping into obvious legal uncertainty like this
would allow for the generation of huge quantities of FUD ("Linux violates its own copyright
license. Do you really trust that it doesn't violate others?"), DMCA takedowns and lawsuits.
Paranoid? Yes. But no major Linux vendor is going to leave themselves open to that for the
sake of a single feature, no matter how attractive it is.

More DTrace envy

Posted Jul 3, 2008 13:44 UTC (Thu) by tzafrir (subscriber, #11501) [Link] (34 responses)

Even worse: Apple might buy all the copyrights from Linus tommorow to all of his works and
relicense them as proprietary (let's make it even worse: CDDL ;-) ). The sky will fall, right?

Not quite.

http://www.fsf.org/licensing/licenses/gpl-faq.html#CanDev...

Any other legal uncertainty?

More DTrace envy

Posted Jul 3, 2008 14:57 UTC (Thu) by mjg59 (subscriber, #23239) [Link] (33 responses)

You've missed the point. If Microsoft (say) end up holding the copyright on part of the
kernel, they get to enforce that copyright. If they interpret the GPL as preventing the
incorporation of the CDDLed dtrace then they get to sue everyone distributing the Linux/dtrace
combination. With that as a possibility, I just don't see any major Linux vendor taking the
risk.

More DTrace envy

Posted Jul 3, 2008 15:29 UTC (Thu) by tzafrir (subscriber, #11501) [Link] (14 responses)

If it was already published as GPL, then they cannot change that. (Otherwise they would have
done so already). That's the nice thing about free software.

BTW: look at the Tentacles of Evil test in
http://en.wikipedia.org/wiki/Debian_Free_Software_Guideli...
. We try to assume the worst. We try to assume that the copyright owners
will suddenly become a second Caldera/SCO. The software must remain usage,
distributable, modifiable etc. even in that case. 

If a software fails that test it won't make it into Debian.

In fact, there are those who claim that the CDDL does not qualify because it fails exactly
that test (due to the choice of venue clause).

More DTrace envy

Posted Jul 3, 2008 15:48 UTC (Thu) by mjg59 (subscriber, #23239) [Link] (13 responses)

No, you're still missing the point. For the sake of argument, we'll assume that using the
CDDLed dtrace code in Linux is a violation of the GPL[1]. Let's also assume that none of the
Linux copyright holders are going to sue anyone who distributes this infringing combined work.
Now let's imagine that Microsoft buy a small Linux contracting company that holds the
copyright for part of the Linux kernel. Microsoft now get to enforce the GPL against anyone
shipping Linux in a way that violates it, and so file takedown notices against Red Hat and
Novell. The only defence these companies would have is "It's not a derivative work of the
kernel", which runs counter to arguments that they've made in the past. Do you really think
anyone wants to be open to that situation?

[1] As Bryan points out, this is a grey area. But I don't see any of the major Linux vendors
being keen on being the first to have that tested in court.

More DTrace envy

Posted Jul 3, 2008 16:04 UTC (Thu) by paulj (subscriber, #341) [Link] (12 responses)

You have completely ignored the "if the Linux copyright holders agree" condition repeated
several times across, at least, my comments.

It is entirely within the power of the copyright holders to define the licence used, including
adding their exceptions to the GPL, such as "incorporating CDDL code is ok". My understanding
is that the Linux licence has even been modified in the past, and unilaterally at that!

We could imagine otherwise, sure. We could also imagine Jonathan Schwartz as He-Man battling
it out with Linus as Skeletor over who is master of Greyskull*... (feel free to mentally
reverse the roles according to preference).

* NB: humour..

More DTrace envy

Posted Jul 3, 2008 16:13 UTC (Thu) by mjg59 (subscriber, #23239) [Link] (9 responses)

Some of the Linux copyright holders are dead. Some have merely vanished. One of them's a
company that tried to kill Linux a few years ago. In some cases we probably don't even have a
solid idea who the copyright holder is. Changing the license isn't a real possibility.

(The last time the license changed was in 1992, when it probably was possible to identify
everyone who'd contributed any code to Linux using a single person's fingers. Since then Linus
has clarified what his interpretation of the license is at various points, but these
clarifications aren't binding)

More DTrace envy

Posted Jul 3, 2008 18:02 UTC (Thu) by paulj (subscriber, #341) [Link] (1 responses)

ISTR some kind of brouha, discussed on LWN I think, not so long ago about Linus changing the
Linux copyright to exclude the possibility of upgrading its GPLv2 to GPLv3 (it was claimed he
hadn't actually changed the licence, but that wasn't accepted all? I dont quite remember).

More DTrace envy

Posted Jul 3, 2008 18:11 UTC (Thu) by paulj (subscriber, #341) [Link]

Huh, nm. You covered the GPLv2 clarification. My bad for not reading.

More DTrace envy

Posted Jul 3, 2008 18:04 UTC (Thu) by paulj (subscriber, #341) [Link] (6 responses)

Oh.. dead copyright holders either have successors in interest, or else they don't matter, is
what I suspect a lawyer would tell me.

More DTrace envy

Posted Jul 3, 2008 18:31 UTC (Thu) by mjg59 (subscriber, #23239) [Link] (5 responses)

Indeed, my understanding is that the copyright will generally end up with whoever holds the
estate. That doesn't make it easy to track them down.

More DTrace envy

Posted Jul 3, 2008 19:18 UTC (Thu) by paulj (subscriber, #341) [Link] (4 responses)

I bet there are ways to solve this problem, such as publicising a proposed change and asking
for objections. Perhaps the law has already dealt with cases where some minority of copyright
holders in a collective work can't be found and/or don't take an interest...

It's not Suns' problem though..

More DTrace envy

Posted Jul 3, 2008 19:33 UTC (Thu) by mjg59 (subscriber, #23239) [Link]

I agree - it's unfortunate for Linux that Sun chose a license that the GPL is incompatible
with, but they were entirely within their rights to do so. My only objection is to the
repeatedly raised "Linux people hate dtrace for irrational reasons" type claims. Linux vendors
feel they can't ship dtrace for justifiable legal reasons, which means that there's little
incentive to work on the technical details. Whatever NIH tendencies the Linux community may
have, they're not the reason for ignoring dtrace.

More DTrace envy

Posted Jul 3, 2008 21:32 UTC (Thu) by bronson (subscriber, #4806) [Link] (2 responses)

No, it's not Sun's problem.  Unfortunately, it's not Linux's problem either -- the GPLv2 was
written 15 years before the CDDL.

It's a mutual problem.

The Linux team is unable to modify the Linux Kernel's license, and the DTrace team sounds
quite unwilling to amend/modify/dual license DTrace, so I guess we're at an impasse.  Can
anything be done?

More DTrace envy

Posted Jul 3, 2008 21:51 UTC (Thu) by paulj (subscriber, #341) [Link] (1 responses)

I'm sure we could find licences which predate the GPL which also would *not* have served
OpenSolaris. E.g. Solaris engineering has a fairly strong BSD background and you can bet that
licence was at least mentioned..

So, sorry, that's just a daft argument.

More DTrace envy

Posted Jul 3, 2008 22:55 UTC (Thu) by bronson (subscriber, #4806) [Link]

Hm, I don't understand.  What is a daft argument?  That it's a mutual problem?  That combining
CDDL and GPL code appears to be at an impasse?

More DTrace envy

Posted Jul 3, 2008 18:35 UTC (Thu) by smoogen (subscriber, #97) [Link] (1 responses)

There are probably over 1000 Linux copyright holders. Getting 100% agreement out of 1000
people is rare if not impossible. One of the bonuses Sun can say as a business argument is
that OpenSolaris is 100% theirs and they can do whatever they want when they want without
having to get such agreement.

More DTrace envy

Posted Jul 3, 2008 19:06 UTC (Thu) by paulj (subscriber, #341) [Link]

Getting 100% agreement out of 1000 people is rare if not impossible.

Asked a lawyer whether 100% of 1000+ is required? It's very tempting for programmers to try interpret law almost programmatically, yet incorrectly. There surely must be case law from the music industry..

This still isn't Suns' problem though. It's not reasonable to expect Sun to open-source Solaris under any licence but one that suits the needs of Solaris users and Suns' business (see Bryan's post, and ealier post of mine).

More DTrace envy

Posted Jul 3, 2008 17:50 UTC (Thu) by bcantrill (guest, #31087) [Link] (17 responses)

Now we've drifted into the absurd.  What are the supposed damages in this hypothetical case?
In the historical conflict between open and closed source, the case for damages is clear:  if
Hacker's GPL code is swiped by Meglocorp and ships as a (closed-source) component in a
Meglocorp product, the revenues from that product are (arguably) damaging Hacker.  But when
all of the components are open source, I don't really see the case for damages -- how could a
Linux copyright holder possibly be harmed by the presence of another open source component in
the same address space?  This is not a theoretical point, by the way:  if there are no
damages, there is no tort.

License incompatibility

Posted Jul 3, 2008 18:42 UTC (Thu) by corbet (editor, #1) [Link] (1 responses)

So you're saying that free software license incompatibility does not exist, at least as far as the US legal system goes?

License incompatibility

Posted Jul 3, 2008 20:23 UTC (Thu) by bcantrill (guest, #31087) [Link]

In terms of the law, I think that the GPL is in a dimly lit area to begin with -- and the
issue of free software license incompatibility extinguishes whatever light remains.  So
strictly in terms of case law, no, it doesn't exist. Not that this is desirable, of course; I
think software desperately needs legal precedent on the linking issue in particular.  If (as I
personally believe) dynamic linking does not create a derived work, there is no real
"incompatibility" issue to speak of, and we can stop wasting our collective time huffing and
puffing about it.  Unfortunately, it is in nearly everyone's best interests (FSF, companies,
lawyers) for this issue to stay murky -- and I expect it to remain so for the foreseeable
future...

More DTrace envy

Posted Jul 3, 2008 18:42 UTC (Thu) by mjg59 (subscriber, #23239) [Link]

The DMCA allows for damages to be set at the profit realised as a result of the infringement
(504(b)). An injunction against Red Hat or Novell would almost certainly be rather more
crippling for them than the actual monetary damages.

More DTrace envy

Posted Jul 3, 2008 20:27 UTC (Thu) by bronson (subscriber, #4806) [Link] (13 responses)

> if there are no damages, there is no tort.

Erm, it's fairly easy to get injunctive relief and attorney's fees even without damages.

On top of this, there are plenty of reasons to sue other than tort.  Unfair competition,
deceptive business practices, breach of contract, etc.  Any of these might apply.

More generally, while article 3 of the constitution leaves this open for interpretation, a few
of the recent Supreme Court decisions have allowed large suits with some awfully vague damages
(Mass v. EPA).  And many states have their own laws, like CA's recent prop 64, that
essentially do allow tort without damages in certain circumstances.

So, depending the state where the lawsuit is brought and the current makeup of the Supreme
Court, your statement ranges from somewhat incorrect to completely false.

So, just because two entites are making no profits, that doesn't mean they can wantonly
violate their mutual licenses and contracts.  Now *that* would be absurd!

More DTrace envy

Posted Jul 3, 2008 20:45 UTC (Thu) by paulj (subscriber, #341) [Link] (5 responses)

So who is going to sue whom on what grounds? Say Novell ships a Linux-DTrace and SCO file for
injunction relief based on their copyright interest in Linux (see mjg's comments). What are
the grounds exactly?

If you really want to find reasons why you can't port DTrace, knock yourself out. Seems a
productive use of energy..

More DTrace envy

Posted Jul 3, 2008 20:55 UTC (Thu) by mjg59 (subscriber, #23239) [Link] (3 responses)

The argument would be that any Linux implementation of dtrace is going to end up being a
derived work of the Linux kernel, and therefore would have to be available under the terms of
the GPL. The CDDL includes restrictions not present in the GPL, making it impossible to
satisfy both licenses simultaneously. Shipping the combined work would therefore be a
violation of the GPL. In the absence of the GPL there's no further permission to distribute
the Linux (and Linux derived) code, and therefore doing so constitutes a copyright
infringement.

Various people have various opinions on the validity of that argument. I'm aware of various
legal opinions that have been professionally offered. To the best of my knowledge, though,
there's no especially useful case law and so it's difficult to know which way the courts would
go. People tend to err on the side of caution when the potential cost (injunctions against
distributing their primary product) outweigh the potential benefit (a single, even if useful,
feature).

More DTrace envy

Posted Jul 4, 2008 0:52 UTC (Fri) by giraffedata (guest, #1954) [Link] (2 responses)

You missed his point. He's saying even stipulating that a Linux copyright holder would have a legal right to stop someone from distributing a Dtrace-enhanced Linux kernel, why would he do it?

The answer lies in the basis of the free software movement: Any free software activist who happens to be a copyright holder and able to stop Red Hat from distributing a Dtrace-enhanced Linux kernel would want to do so. The movement is about encouraging the proliferation of free software by restricting the proliferation of less free software, using copyright. So yes, he would deprive the world of Linux Dtrace so that 1) he wouldn't be personally contributing to the expansion of less free software, and 2) to put pressure on Red Hat to create some GPL alternative.

It's the same reason Linux people have sued router manufacturers for distributing enhanced Linux kernels that contain code for which you can't get the source.

More DTrace envy

Posted Jul 4, 2008 12:14 UTC (Fri) by mjg59 (subscriber, #23239) [Link]

You missed his point

No, I didn't.

More DTrace envy

Posted Aug 31, 2008 20:10 UTC (Sun) by rlhamil (guest, #6472) [Link]

> The movement is about encouraging the proliferation of free software by restricting the
> proliferation of less free software, using copyright.

_That's_ what makes me crazy about the GPL: to advance the Cause and preserve one's
own freedom, it restricts other freedoms that might have more immediate practical benefit.

I never saw how some could argue that BSD is _less_ free than GPL, especially the GPL
adherents, from whom there's usually the sucking sound of one-way transfers of code
from BSD to GPL. Someone creating a proprietary fork of a BSD licensed program takes
away _nothing_ from the freedom of those who continue to retain access to the pre-fork
original.

GPL strikes me as equivalent to the mandatory volunteerism one sees in high schools today
(community service as a requirement of passing). A great idea to _offer_ such a thing, but
apalling to require it. There _is_no_virtue_ when virtue is enforced rather than chosen
freely!

Nevertheless, I don't deny it serves a purpose, just that its purpose is not and should not
be the only one worth serving.

Sure would be nice if someone worked out a way to dual-license that required that
derivatives of the dual-licensed code remain subject to the choice of license, but
was otherwise clearly non-viral, so that neither side could lay claim to more than what
they brought to the table, allowing DTrace, and zfs (native, not FUSE) on Linux, for example.
The source file scope of CDDL seems to me useful in that regard, avoiding issues about
static vs dynamic linking and binaries altogether. Despite that having more practical benefit
to Linux (which could then receive dual-licensed code) than OpenSolaris (for which I doubt
GPL ideologues and Linux zealots would choose to return the favor by dual-licensing
anything), simply getting more input might well at least improve the software shared as
a result faster than the originators alone could do so.

IMO, the _real_ problem isn't license incompatibility so much as it is what causes a lot of
it: hardware with closed specifications and thus closed drivers. But given the often blurry
line between hardware and software, enouraging open hardware specs might require
tolerating at last _narrowly scoped_ software patents, which are landmines in their own
right.

There may not be any good answers given a range of perfectly legitimate if widely varying
interests. But I'd sure like to see an attempt to strike a different balance between
ideology (which carried to its logical conclusion is often self-contradictory) and pragmatic
concerns (which arguably are often short-sighted). And though they're not the same thing,
both cooperation _and_ competition serve a purpose; on the far side of Eternity, there may
be One True Answer, but until then, a selection of approaches remains useful, especially
given the power-tripping that those who think they have the One True Answer prematurely
tend to eventually descend to.

More DTrace envy

Posted Jul 3, 2008 22:46 UTC (Thu) by bronson (subscriber, #4806) [Link]

> So who is going to sue whom

Doesn't matter.

> on what grounds?

From my previous post: unfair competition, deceptive business practices, breach of contract,
etc.  Depends on the circumstances and parties.

> If you really want to find reasons why you can't port DTrace, knock yourself out.

Nobody's trying to create reasons not to port DTrace if that's what you're implying.  But
here's the thing: if it isn't clearly legal and moral to snake someone else's code, then it's
only considerate and safe to assume that you can't!

I've been searching for reasons to believe that they're compatible but I haven't found any
clear legal statement from Sun or anyone else, nor even any tiny nugget of estoppel.  Did Sun
ever produce the Devleoper's Bill of Rights?
http://www.cbronline.com/article_news.asp?guid=3B8EDD57-1...

More DTrace envy

Posted Jul 3, 2008 22:10 UTC (Thu) by bronson (subscriber, #4806) [Link] (6 responses)

I showed my engineer-attemptls-law post to a friend and she said:

> Sometimes when you sue for breach of contract, you can be awarded restitutionary damages
which means that even if you can't prove that you have been damaged, you can be awarded money
equivalent to the other party's "ill gotten gain".  So if the other party unfairly got some
advantage that was, for lack of a better term "unfair", you could recover their gain just
because it is unfair for them to keep it.

> That's one reason why it is dangerous for profitable companies to use open source code.  You
use code in a way that breaks your contract with the programmer ... that programmer could
recover your "ill gotten gain".

Wow.  Now I'm curious if this has been used in any of the GPL violation cases.  I'll have to
watch them a little closer!

More DTrace envy

Posted Jul 3, 2008 22:47 UTC (Thu) by bcantrill (guest, #31087) [Link] (2 responses)

You (or rather your friend) is making my point:  the restitutionary damages that she mentions
are the case of Meglocorp shipping GPL'd goober in proprietary product, and Hacker suing for
damages.  That's not the case that was being floated; the assertion was that Meglocorp would
become a Linux copyright holder and then could sue when CDDL'd source was distributed with
the(ir) GPL'd source.  I don't see what the damages are in this case -- compensatory or
restitutionary.  I think if it's flipped around -- Meglocorp ships GPL'd+CDDL'd goober, Hacker
sues because GPL has been violated -- one at least has a case, but I happen to think it's an
extraordinarily weak case: it relies on both an expansive definition of a derived work, and a
creative approach to damages.

More DTrace envy

Posted Jul 3, 2008 22:58 UTC (Thu) by mjg59 (subscriber, #23239) [Link]

Nobody knows how far the derived work clause of the GPL would actually reach. Staking your
future business to a legal gamble isn't a move many people are willing to make without a large
resulting benefit, and dtrace simply isn't perceived as a sufficiently large benefit. It's
perfectly rational reasoning.

More DTrace envy

Posted Jul 4, 2008 0:03 UTC (Fri) by bronson (subscriber, #4806) [Link]

> Meglocorp ships GPL'd+CDDL'd goober, Hacker sues because GPL has been violated

Agreed. This is the only one that seems plausible. But proving damages seems to be rather
easy nowadays. And just about anybody involved with Meglocorp could sue; it doesn't have to
be a Linux kernel hacker.

Here's the big-picture problem as I see it: after the SCO disaster, the Linux kernel devs will
not incorporate any code of questionable license status into the kernel. They want to keep
the entire tree completely unencumbered by legal issues. It was a good lesson at a good time.

So, until it can be demonstrated that CDDL and GPL code absolutely can be mixed, they won't
accept CDDL-licensed code into the kernel. it's just too risky.

As far as derived work, while I agree that those parts of the GPL are horribly murky and
untested, I don't think it's very relevant here... Even if someone *could* claim that DTrace
is a derived work (a stretch!), as long as the CDDL+GPL combination is "licensed as a whole at
no charge to all third parties under the terms of [the GPL]" everything is good. If the CDDL
and the GPL are compatible, the terms of the GPL are met, and the whole derived work issue is
moot. (Right?)

To make CDDL+GPL compatible, IIUC the patent issues just need to be resolved the way Mozilla
did with the MPL. Everything else in the CDDL and the GPL is compatible today. (I'm no
expert though so I'd sure value someone else's opinion. That almost sounds too easy!)

It would be nice to see someone reject license prejudices and try to maintain an out-of-tree
DTrace-Linux but... can you imagine? The git-rebases would make the even the heartiest
programmer cower in fear!

Contracts

Posted Jul 3, 2008 23:13 UTC (Thu) by corbet (editor, #1) [Link] (2 responses)

This scenario, of course, depends on the idea that the GPL is a contract; the people who wrote the GPL did not intend that, however; they wrote a license. Assuming that legal reasoning holds, there's no contract to be sued for breaching. And no, I do not believe any GPL-violation case has been a breach-of-contract case; they are copyright infringement cases.

Contracts

Posted Jul 3, 2008 23:17 UTC (Thu) by bcantrill (guest, #31087) [Link]

Yes, the authors did intend it to be a license -- but the attorneys that I have spoken with on
this issue believe that the expansive views of the GPL require it to be interpreted as a
contract.  Again, some case law here would be quite helpful...

Contracts

Posted Jul 4, 2008 0:22 UTC (Fri) by bronson (subscriber, #4806) [Link]

http://lwn.net/Articles/61292/

That's a relief, although it does diminish the chances of me finding my code in the Google
Toolbar and making a quick hundred million.  :)

More DTrace envy

Posted Jul 3, 2008 16:30 UTC (Thu) by smoogen (subscriber, #97) [Link]

Various parts of Sun went at each other with iron tongs when SunView was looked at being
opensourced back in the early 1990's. It is just harder to sue each other inside of a
corporation. [I think parts of IBM tried that in the 1960's.]

More DTrace envy

Posted Jul 5, 2008 17:55 UTC (Sat) by brouhaha (guest, #1698) [Link]

(least until the *AA succeed in making copyright infringment a criminal matter)

Huh? They succeeded at that 16 years ago! Felony copyright infringement was introduced with the Copyright Felony Act of 1992, and extended by the No Electronic Theft Act of 1997.

More DTrace envy

Posted Jul 3, 2008 8:37 UTC (Thu) by nhippi (subscriber, #34640) [Link] (1 responses)

NIH: Exactly what technology from Linux kernel has Solaris adopted instead of re-implementing
it yourself?
License: If the licensing is so unclear, how come there is no GPL code mixed into Solaris? I'm
fairly certain it's not a smokescreen or amateur opinion, but something professional Sun
lawyers said would be best...

Don't get me wrong, I'm happy for all the things sun has contributed, but the amount of
licensing misery caused by inventing (NiH!) yet another license, CDDL, is very real.

More DTrace envy

Posted Jul 7, 2008 2:59 UTC (Mon) by clump (subscriber, #27801) [Link]

License: If the licensing is so unclear, how come there is no GPL code mixed into Solaris?

You have a valid point. I'm curious what the Sun employees who are commenting here have to say about this.

More DTrace envy

Posted Jul 9, 2008 22:43 UTC (Wed) by Tet (subscriber, #5433) [Link] (1 responses)

good 'ole NIH in the Linux community

You could try to be less inflamatory. DTrace was hardly an original idea at Sun, either. You claim SystemTap is a "Linux-born DTrace-knockoff". By that logic, I could claim that DTrace is a Sun-born knockoff of the tracing work IBM did years ago. Sure, Sun have made some big improvements to the art of tracing, such as the D language, and a massive improvement it was too. As are some of the other innovations that have come from DTrace. But that's how the progress is made in this industry -- by building on work done by others. DTrace is not the be all and end all of tracing, and claiming that NIH is the reason behind SystemTap doesn't really help anything at the end of the day. Both DTrace and SystemTap are useful products and have their place in the world. DTrace is good enough to stand on its own technological merits, without the needless put downs aimed at SystemTap (which pretty much everyone agrees is currently lagging DTrace by some margin). You're rightfully proud of the work you've done on DTrace, but perhaps a little less hostility to the competition might be appropriate...

More DTrace envy

Posted Jul 9, 2008 22:58 UTC (Wed) by bcantrill (guest, #31087) [Link]

By that logic, I could claim that DTrace is a Sun-born knockoff of the tracing work IBM did years ago.

I'll call that bluff. What technology are you referring to, exactly? Or more concisely, in our 2004 USENIX paper, what piece of related work did we neglect? I'm eager to see what technology you're going to parade out as an example of dynamic instrumentation done "years ago" at IBM -- at least we'll be talking about concrete technology and not licensing!