Re: [PATCH] clockevents: avoid unnecessary reprograming of event timer

[Michael Davidson]

On Fri, Feb 13, 2009 at 12:22 AM, Ingo Molnar <mingo@xxxxxxx> wrote:
>
> Hm, given that a good high-res source has nanoseconds resolution,
> what's the chance of this optimization triggering in practice?
> Near zero i think - unless we trigger useless reprogramming without
> having added or removed any new timers - but then we should
> concentrate on analyzing the reason for that redundant reprogramming.
>
> Does it trigger often for you?

Yes - running 2.6.26 built with CONFIG_NO_HZ on a 4 core AMD system,
depending on the workload I see it trigger between 40 and 100 times a second.

I will take a closer look at why this is happening.

md
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