Letters to the editor

Scalability is a double edged sword...

 
A unix kernel with very fine grained locking exists already. It is called
solaris and nobody is impressed with its performance on small systems. If you
have a 64+ processor Ultra Enterprise 10000, or whatever it's current
equivalent is, the fine grained locking is a big win. If you only have 3 or
fewer processors the locking costs more than the time saved by reduced lock
contention. At least one MPI implementation is also guilty of sacrificing
performance on small systems, like the systems the many people have access to,
at the altar of scalability.
 
I think it would be a mistake for Linux to follow the policy of sacrificing
performance on small systems just for scalability to vast numbers of processors,
which practically nobody using linux has. Scalability improvements that also
help small systems should be pursued instead, for example the O(1) scheduler.
If the lack of scalablity to vast numbers of processors is an issue for you
then you can presumably afford to buy solaris, unicos max, or whatever.
 
The spin lock deadlock issue is probably best resolved by a simple, well
maintained, list of spinlock in increasing or decreasing order. Deadlock is,
provably, avoided if you always take locks in the same order everywhere, which
should be moderately easy given such a list. I, perhaps forunately, am not in a
position to construct or maintain such a list. Victims^H^H^H^H^H^H^Hvolunteers
who are in a position to do so should probably file their application on the
linux kernel mailing list.
 
P.S. I do have some (paper) claims to knowledge of parallel systems. Just when
it was freshly minted parallel systems went out of fashion :-(
 
--
Duncan (-:
"software industry, the: unique industry where selling substandard goods is
legal and you can charge extra for fixing the problems."
 

Comments (3 posted)

Switching Back. (Don asbestos: your very first assertion was wrong!)

 
> Mr Joe Average is someone who wants to install their OS, boot it up,
> and it works.
 
No. Mr Joe Average User doesn't want to install his OS at all. He just wants
it to work. You are _not_ Joe Average.
 
Mandrake Linux 8.2 does that, when you install it, it stays installed. No DLL
hell, no random lockups.
 
Even if poor Joe is left to install his own OS, Mandrake is easier to do this
with than Windows even for many scanners, cameras, USB ADSL modems and other
mechanisma obscurata. Pretty good for an OS without billions of dollars of
influence behind it to help manufacturers decide to write drivers for it.
SuSE, I am told, is about the same.
 
> He wants to be able to upgrade his PC, and have the hardware work in a
> few short minutes.
 
Agree. It's called HardDrake, and the hardware works pretty much instantly.
 
> Stupid users don't doggedly stick at something for three and a half years,
> trying distribution after distribution in the hope of finding the holy
> grail of Linux desktops.
 
Sorry, I have trouble connecting the preposition with the reasoning...? (-:
 
> They give up in less than a few hours of trying to (unsuccessfully)
> install RedHat Linux.
 
If it was something new to you, I would expect a *clever* user to either give
up or call for help after a few hours of futility. RedHat do have support, but
I generally turn to the community.
 
What do you do when faced with the same situation in Windows? Call Microsoft?
The technical term for move that is `a cwoft' (Complete Waste Of Time).
 
If you're on the verge of claiming that this never happens, don't. I'll bury
you in real-life counterexamples - with names - down to a machine which acts
like it's been virussed (files go missing, sooner or later it wipes most of
the disk in one go and the machine dies) when Win98SE is installed on it, but
works flawlessly with Linux. Yes, we did run a modern virus scanner over it.
 
> I was getting tired of the 'stable' Debian release being so out of date,
> and the 'unstable' distribution being so... well... unstable.
 
You were too impatient. Debian now has a `testing' branch which has the mix
you dream of.
 
> My experience with X is that it's too big, bloated, slow and unstable to
> be any good to the home user. [...] What home users need is something
> small and fast, so they can run local applications efficiently.
 
On one hand, I have home users completely happy with X, playing BZflag,
TuxRacer, The Sims and the like. On the other, perhaps you want to try Berlin
or one of the direct framebuffer drivers.
 
> Fonts are truly awful under X.
 
Can be. They work fine (antialiased) under Mandrake 8.2 for me, but I know of
others who have trouble. FontDrake co-ordinates font installation for the
diverse font-using systems within my boxes.
 
Fonts are worth discussing. While there are some good justifications for those
diverse systems, I personally think that having everything able to get fonts
from some single source like xfs would be a good idea. Unlike Windows, if you
also think this is a good idea, there's no impassible obstacles standing
between you and (for example) Ghostscript to prevent you from making it so.
 
For an example of justifying a diverse system, any UNIX app can make a
PostScript file with a limited set of fonts and know that it is printable,
rather than having to learn and link to a complex GDI which wiggles. But
we've digressed again from Joe Average.
 
> and use a readable naming scheme as well.
 
There is nothing stopping you from mapping simple names like "Courier 15" to
the full name of a font. GIMP, for example, does this. I do agree that a
standard way of doing this is worth while. I do _not_ agree that dumbing down
fonts to suit dumb users is a good idea. Computers are good at translating,
so let the computer translate dumb concepts to suit a powerful underlying
metaphor.
 
> Got RedHat Linux 7.3? Perhaps you run SuSE 7.3 or Debian 2.2. You'll have
> to download a binary package specific to your distro.
 
The vast majority of devices are dealt with by a driver already present in the
kernel; of the remainder, most manufacturer's sites have a small set of
generic drivers which suit (for example) all 2.2 and another for all 2.4
kernels, just like most have generic drivers for all Win95/98/ME and another
set for NT/2k/XP.
 
I think thrice in my life as a Linux consultant have I had to download drivers
for stuff, one being an esoteric multiport serial board, one being a NetGear
FA311 network card when it was brand new and `modprobe natsemi' didn't work
for it, and the third being a NetComm Lucent-based software modem (which
works faster and more stably under Linux, BTW).
 
> I believe that a home user shouldn't have to do more than plug it in. It's
> an IDE device, it's not that complicated!
 
Earth to Tony? Did I just hear you advocate having Joe Average - or perhaps to
make the point plain, Joe Sixpack, the supermarket-PC-and-AOL user - messing
around inside his case?
 
And do you recall having on several distinct occasions to download and install
Windows software (and reboot, what a surprise!) to deal with bigger IDE hard
drives at certain size boundaries?
 
> I'll put this simply. I'm a home user, not a programmer. Why on earth
> should I have to compile the software I want to use?
 
You don't. Either use the package provided in many cases, or accept that your
market is currently much less than 1/20th of the Windows market and be
prepared to wait for pre-built apps. Meanwhile, go search on rpmfind.net and
in you distro's contrib directory, someone other than the authors may have
packaged it for you.
 
This, it is worth noting, is not a service available to Windows users. If you
want to compile software for your Windows box (e.g., to optimize it for your
CPU, or make a version for your CPU type - oops, hang on, Windows only has
one supported CPU type... :-).
 
Now let me pose you a question: why on Earth should I have to pay AUD$495
(retail price of XP) for an OS to run on my AUD$599 computer? And then why on
Earth should I have to pay another AUD$265 for a virus scanner (Sophos) that
works reliably and doesn't tinker too much with your system's internals?
 
Think about that: I've just spent $760 on `necessary' software for a $600 box.
You did pay for your version of Windows, didn't you? Alternatively I can get
a supermarket box with XP pre-installed for AUD$1200 and _then_ pay AUD$265
for AV software which works. Yay.
 
Contrast this with adding Mandrake Linux 8.2 at AUD$10 for the download
edition burnt to CDs or AUD$129 for the PowerPack with a swathe of commercial
software on top of the 3000-odd Open Source packages (including three
complete office suites) from the download edition. Better support, too. (-:
 
> cdrecord [...] refused to allow me to copy a cd directly.
 
That's never been a problem for me, even with early versions of cdrecord.
 
Also, I can just copy a CD onto the hard drive as an image, mount it and have
access to the files on it, no special software required - or burn from the
HDD copy.
 
> Although having package databases (such as the rpm and deb systems use) is
> great, there should definitely be seperation between system packages and
> additionally installed software. There needs to be a standard installer
> and database for user-installed applications such as word processors,
> email clients and games, and it should be seperate from the rpm or deb
> databases used for system software such as lilo, init and cron. This will
> make it much easier for home users to know what applications they have
> installed on their PC, and to easily uninstall them if necessary, without
> knowing some arcane commands and weird package names.
 
Oh, be still, my aching ribs! (-:
 
Is IE an application, or not? How do I uninstall it? Gee, aren't those
commands you've given me just a tad arcane? Did they come from Microsoft's
web site?
 
There are scores of GUI package managers available, most of which will show
you dependencies, descriptive information, which package owns what file and
so on. Where in Windows do I go to find out who owns the file
C:\WINDOWS\SYSTEM\VBRUN700.DLL?
 
> This may not apply to most of the community, but there is a very vocal
> minority that gives Linux a bad name.
 
Likewise for anything, in any arena. If you can't see a similar vocal minority
in the Windows crowd, I suggest looking up Alex Boge, AKA Drestin Black. The
point you've made holds true for football, geology, democracy, avocado
farmers, name it.
 
> My CDRW worked right away, without a hitch.
 
Mine did too. However, I can point you to a Windows guru (and this guy really
is a genius) who finally gave up and replaced his CDRW drive with another
because the software that drove it under Win2k would never work. He did not
have the option of "hdc=ide-scsi", LILO and reboot.
 
> A quick install of Nero Burning Rom, and I was able to make a backup copy
> of my game CDs.
 
I didn't need to install anything to do that. The Mandrake installer already
had it sorted.
 
> All [W]indows software comes in binaries, either with an installer or in a
> zip file. I hope to never compile an application ever again.
 
Instant counter: http://solon.cma.univie.ac.at/~neum/software/arfit/ plus
gazillions of other packages like BlueFish, which will (in this case with the
Windows GTK libraries) run under Windows but are not packaged for it.
 
We're talking about Joe Average here, else I'd be asking if you now have tools
for recompiling an application, should you wish to alter one...?
 
> I can't comment on the Windows using community yet. I've not yet had a
> problem that a simple point and click couldn't fix.
 
You will. (-:
 
> However, I will say that my original concern with Windows '95 has been
> addressed in Windows XP. The stability is finally there.
 
Generally, and speaking from exposure to scores of XP machines (including
fixing them and having to use them, horrah for CygWin): better than 95, worse
than NT. How about security? Socket and see. (-:
 
> I expect that the Linux community will have something to say about this
> article;
 
<horrified>No! Really...?</horrified> (-:
 
If you state up front that this article is *not* about Joe Average user, but
about *your*own* needs and experiences, demi-power-user, it will be a lot
more believable.
 
Come to LCA2003 and discuss it in person!
 
Cheers; Leon
 
--
CyberKnights Modern tools, traditional dedication.
+61-409-655-359 http://www.cyberknights.com.au/
 
linux.conf.au 2003 The Australian Linux Technical Conference
http://conf.linux.org.au/ 22-25 January 2003 in Perth, Western Australia

Comments (1 posted)

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