Messages in this thread Patch in this message | | | Subject | Re: VolanoMark regression with 2.6.27-rc1 | From | Peter Zijlstra <> | Date | Mon, 04 Aug 2008 08:54:26 +0200 |
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On Mon, 2008-08-04 at 11:23 +0530, Dhaval Giani wrote:
> Peter, vatsa, any ideas?
--- Subject: sched: scale sysctl_sched_shares_ratelimit with nr_cpus
David reported that his Niagra spend a little too much time in tg_shares_up(), which considering he has a large cpu count makes sense.
So scale the ratelimit value with the number of cpus like we do for other controls as well.
Reported-by: David Miller <davem@davemloft.net> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> --- diff --git a/kernel/sched.c b/kernel/sched.c index 9a76e92..7eddaea 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -809,9 +809,9 @@ const_debug unsigned int sysctl_sched_nr_migrate = 32; /* * ratelimit for updating the group shares. - * default: 0.5ms + * default: 0.25ms */ -const_debug unsigned int sysctl_sched_shares_ratelimit = 500000; +const_debug unsigned int sysctl_sched_shares_ratelimit = 250000; /* * period over which we measure -rt task cpu usage in us. @@ -5732,6 +5732,8 @@ static inline void sched_init_granularity(void) sysctl_sched_latency = limit; sysctl_sched_wakeup_granularity *= factor; + + sysctl_sched_shares_ratelimit *= factor; } #ifdef CONFIG_SMP
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