RE: 2.6.27-rc5 OLTP performance regression

[Ma, Chinang]

I increased the /proc/sys/kernel/sched_shares_ratelimit from 1 millisecond to one second to reduce the frequency of shares update. That was okay for OLTP workload. As Peter mentioned, a larger value will reduce the accuracy of SMP fairness for group scheduler and the ratelimit and using a larger default value may not be good for general case.

Thanks,
Chinang
-----Original Message-----
From: Ingo Molnar [mailto:mingo@xxxxxxx]
Sent: Wednesday, September 10, 2008 5:26 AM
To: Ma, Chinang
Cc: Peter Zijlstra; Srivatsa Vaddagiri; Mike Galbraith; Gregory Haskins; Steven Rostedt; Nick Piggin; Siddha, Suresh B; Wilcox, Matthew R; Tripathi, Sharad C; Chilukuri, Harita; linux-kernel@xxxxxxxxxxxxxxx
Subject: Re: 2.6.27-rc5 OLTP performance regression


* Ma, Chinang <chinang.ma@xxxxxxxxx> wrote:

> Peter,
>         We increased sched_shares_ratelimit and were able to recover
> the 2% performance regression. [...]

great. Could you please post a patch for that?

        Ingo
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