Re: [REPORT] cfs-v4 vs sd-0.44

[Con Kolivas <kernel@kolivas.org>]

On Sunday 22 April 2007 04:17, Gene Heskett wrote:
> More first impressions of sd-0.44 vs CFS-v4

Thanks Gene.
>
> CFS-v4 is quite smooth in terms of the users experience but after prolonged
> observations approaching 24 hours, it appears to choke the cpu hog off a
> bit even when the system has nothing else to do.  My amanda runs went from
> 1 to 1.5 hours depending on how much time it took gzip to handle the amount
> of data tar handed it, up to about 165m & change, or nearly 3 hours pretty
> consistently over 5 runs.
>
> sd-0.44 so far seems to be handling the same load (theres a backup running
> right now) fairly well also, and possibly theres a bit more snap to the
> system now.  A switch to screen 1 from this screen 8, and the loading of
> that screen image, which is the Cassini shot of saturn from the backside,
> the one showing that teeny dot to the left of Saturn that is actually us,
> took 10 seconds with the stock 2.6.21-rc7, 3 seconds with the best of
> Ingo's patches, and now with Con's latest, is 1 second flat. Another screen
> however is 4 seconds, so maybe that first scren had been looked at since I
> rebooted. However, amanda is still getting estimates so gzip hasn't put a
> tiewrap around the kernels neck just yet.
>
> Some minutes later, gzip is smunching /usr/src, and the machine doesn't
> even know its running as sd-0.44 isn't giving gzip more than 75% to gzip,
> and probably averaging less than 50%. And it scared me a bit as it started
> out at not over 5% for the first minute or so.  Running in the 70's now
> according to gkrellm, with an occasional blip to 95%.  And the machine
> generally feels good.
>
> I had previously given CFS-v4 a 95 score but that was before I saw the
> general slowdown, and I believe my first impression of this one is also a
> 95.  This on a scale of the best one of the earlier CFS patches being 100,
> and stock 2.6.21-rc7 gets a 0.0.  This scheduler seems to be giving gzip
> ever more cpu as time progresses, and the cpu is warming up quite nicely,
> from about 132F idling to 149.9F now.  And my keyboard is still alive and
> well.

I'm not sure how much weight to put on what you see as the measured cpu usage. 
I have a feeling it's being wrongly reported in SD currently. Concentrate 
more on the actual progress and behaviour of things as you've already done.

> Generally speaking, Con, I believe this one is also a keeper.  And we'll
> see how long a backup run takes.

Great thanks for feedback.

-- 
-ck