Linux 2.2 and 2.4 VM systems analysed

Linux 2.2 and 2.4 VM systems analysed

[Derek Glidden]

I've been following the 2.4 VM issues since the early 2.4-pre days.  As
a "power user" and someone who uses Linux at work, the kernel's
stability is of great interest to me.  Finally, I got sick of trying to
interpret the data from various sources on how well the 2.4 VM systems
perform overall and in comparison with each other and other systems.  So
I ran my own tests against 2.4.12-ac6, 2.4.13, and 2.2.19 and wrote up
the results:

"An analysis of three Linux kernel VM systems"

http://www.nks.net/linux-vm.html

The conclusion in a nutshell is that yes, the 2.4 kernel VM systems
still have a few quirks to work out, but overall they are so
significantly better than the 2.2 VM that there really is no
comparison.  

However, this "significantly better" conclusion is for certain
high-stress situations where the 2.2 VM apparently fails entirely, while
2.4 chugs along with barely a notice.  

For overall end-user experience, 2.2 still "feels" better overall with
better interactive responsiveness under a varying set of loads even
though 2.4 really is faster at doing the actual work.

Comments, responses, suggestions welcome.  Flames will be cheerfully
redirected to /dev/null.

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print+x"C*",@a}';s/x/pack+/g;eval 

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Re: Linux 2.2 and 2.4 VM systems analysed

[Miquel van Smoorenburg]

In article <3BE1A790.25B7E6F5@illusionary.com>,
Derek Glidden  <dglidden@illusionary.com> wrote:
>For overall end-user experience, 2.2 still "feels" better overall with
>better interactive responsiveness under a varying set of loads even
>though 2.4 really is faster at doing the actual work.

Well today I switched my workstation (128 MB RAM, 256 MB swap)
over from 2.2.19 to 2.4.14-pre6. With mozilla, netscape, postgres,
perl, apache, X, gnome running I'm usually ~80 MB into swap.
With 2.2.19 you really don't want to do this. It's *slow*.
Early 2.4.x, ditto. But under 2.4.14-pre6, it flies. I'm happy.

Mike.
-- 
"Only two things are infinite, the universe and human stupidity,
 and I'm not sure about the former" -- Albert Einstein.

Re: Linux 2.2 and 2.4 VM systems analysed

[Rik van Riel]

On Thu, 1 Nov 2001, Derek Glidden wrote:

> "An analysis of three Linux kernel VM systems"
>
> http://www.nks.net/linux-vm.html


Nice, finally somebody has taken the time to do
some more rigourous testing ;)

I like this document...

regards,

Rik
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Re: Linux 2.2 and 2.4 VM systems analysed

[Kilobug]

Derek Glidden wrote:

 > "An analysis of three Linux kernel VM systems"
 >
 > http://www.nks.net/linux-vm.html

Very interesting article.

I think it'ld be great to ask many people with different hardware to do 
the same kind of tests on different hardware to see the results.
I don't have the time time, but in a week or two I'll gladly run them on 
my computers if this can help.
(I've an Athlon 1.2G with 512M of DDR and an UDMA-66 hard disk)
But it'll be more interesting if the test "protocol" is somehow 
standardized. (and don't use commercial softwares, I don't own Oracle so 
I can't run a test needinf Oracle).

A linux user that want to give a small amount back in exchange to the 
great work you all do on Linux,

-- 
  ** Gael Le Mignot, Ing3 EPITA, Coder of The Kilobug Team **
Home Mail : kilobug@freesurf.fr          Work Mail : le-mig_g@epita.fr
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Re: Linux 2.2 and 2.4 VM systems analysed

[john slee]

On Fri, Nov 02, 2001 at 12:42:00AM +0100, Kilobug wrote:
> standardized. (and don't use commercial softwares, I don't own Oracle so 
> I can't run a test needinf Oracle).

oracle can be downloaded and legally used for personal non-commercial
purposes i believe

it doesn't make it "free" in the way this community generally uses the
term but it does let you test linux with a very popular application.

i hope you're not using a modem, it's a 3-cd download :-(

j.

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