Re: Sched - graphic smoothness under load - cfs-v13 sd-0.48

Bill Davidsen
2007-05-23T20:44:48Z

Miguel Figueiredo wrote:
> Bill Davidsen wrote:
>> I was unable to reproduce the numbers Miguel generated, comments
>> below. The -ck2 patch seems to run nicely, although the memory
>> repopulation from swap would be most useful on system which have a
>> lot of memory pressure.
>>
>> I spent a few hours running the -ck2 patch, and I didn't see any
>> numbers like yours. What I did see is going up with my previous
>> results as http://www.tmr.com/~davidsen/sched_smooth_04.html. While
>> there were still some minor pauses in glxgears with my test,
>> performance was very similar to the sd-0.48 results. And I did try
>> watching video with high load, without problems. Only when I run a
>> lot of other screen-changing processes can I see pauses in the display.
>>> Your subjective impressions would be helpful, and you may find that
>>> the package in the www.tmr.com/~public/source is slightly easier to
>>> use and gives more stable results. The documentation suggests the
>>> way to take samples (the way I did it) but if you feel more or
>>> longer samples would help it is tunable.
>>>
>>> I added Con to the cc list, he may have comments or suggestions
>>> (against the current versions, please). Or he may feel that video
>>> combined with other heavy screen updating is unrealistic or not his
>>> chosen load. I'm told the load is similar to games which use threads
>>> and do lots of independent action, if that's a reference.
>>>
>> I'll include the -ck2 patch in my testing on other hardware.
>>
>
> Hi Bill,
>
> the numbers i posted before are repeatable on that machine.
>
The numbers you posted in <46534C31.1060306@debianpt.org> are not the
same... From my inbox I grab some very non-matching values:
=====
Here's the funny part...

Lets call:

a) to "random number of processes run while glxgears is running",
gl_fairloops file

b) to "generated frames while running a burst of processes" aka "massive
and uknown amount of operations in one process", gl_gears file

kernel 2.6.21-cfs-v13 2.6.21-ck2
a) 194464 254669
b) 54159 124
=====

The numbers in your glitch1.html file show a close correlation for cfs
and -ck2, well within what I would expect. The stddev for the loops is
larger for -cf2, but not out of line with what I see, and nothing like
the numbers you originally sent me (which may have been testing
something else, or from an old version before I made improvements, or
???). In any case thanks for testing.

>
> I did run, again, glitch1 on my laptop (T2500 CoreDuo, also Nvidia)
> please check: http://www.debianpt.org/~elmig/pool/kernel/20070523/
>
>
Thanks, those data seem as expected.

--
bill davidsen <davidsen@tmr.com>
CTO TMR Associates, Inc
Doing interesting things with small computers since 1979