Re: Nick's scheduler v16 - reaim

From: Nick Piggin
Date: Wed Oct 22 2003 - 21:03:35 EST




Cliff White wrote:



I'm starting to do some large SMP / NUMA testing. Fixed and changed quite
a bit. It isn't too bad, although I'm only testing dbench, tbench, and
volanomark at the moment.

These SMP and NUMA changes are not tied to my interactivity stuff, so its
possible they could get included if they turn out well. If you find any
problems with it (high end or interactivity), please let me know.



Results from reaim aren't encouraging.
patch was applied against 2.6.0-test8 - the result
is PLM #2232

STP id kernal name Max JPM Max User Pct elevator
281932 nick_v16 4923.08 60 0.00 AS
281933 nick_v16 5196.06 68 5.54 deadline
281722 linux-2.6.0-test8 5432.77 92 9.38 deadline
281792 2.6.0-test8-mm1 5384.41 92 8.56 deadline
281790 2.6.0-test8-mm1 5392.65 88 8.7 AS

The kernel doesn't perform well at larger user numbers.
Notice the different in max users.
Compare the graphs for jobs per minute, the usual graph
is quite flat, see:
http://khack.osdl.org/stp/281932/results/jpm.png

With the v16 scheduler, jobs per minute falls off rapidly
as user number increases giving graph with a steep slope, not good.
http://khack.osdl.org/stp/281790/results/jpm.png
Further results: http://www.developer.osdl.org/reaim/index.html


Hi Cliff,

Yeah, unfortunately this graph has been a feature of my scheduler for
quite a while :( I think it is caused either by too much balancing
or timeslices getting too small because there are a lot of threads
blocking. Anyway, if you had the time to test this one would be really
good.

http://www.kerneltrap.org/~npiggin/v16/sched-rollup-nopolicy-v16.gz

Nick

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/