Re: [Announce] [patch] Modular Scheduler Core and Completely Fair Scheduler [CFS]

Ingo Molnar
2007-04-17T09:59:50Z

* Nick Piggin <npiggin@suse.de> wrote:

> 2.6.21-rc7-cfs-v2
> 534.80user 30.92system 2:23.64elapsed 393%CPU
> 534.75user 31.01system 2:23.70elapsed 393%CPU
> 534.66user 31.07system 2:23.76elapsed 393%CPU
> 534.56user 30.91system 2:23.76elapsed 393%CPU
> 534.66user 31.07system 2:23.67elapsed 393%CPU
> 535.43user 30.62system 2:23.72elapsed 393%CPU

Thanks for testing this! Could you please try this also with:

echo 100000000 > /proc/sys/kernel/sched_granularity

on the same system, so that we can get a complete set of numbers? Just
to make sure that lowering the preemption frequency indeed has the
expected result of moving kernbench numbers back to mainline levels. (if
not then that would indicate some CFS buglet)

could you maybe even try a more extreme setting of:

echo 500000000 > /proc/sys/kernel/sched_granularity

for kicks? This would allow us to see how much kernbench we lose due to
preemption granularity. Thanks!

Ingo