Re: Network slowdown due to CFS

From: Ingo Molnar
Date: Mon Oct 01 2007 - 13:09:34 EST



* Chris Friesen <cfriesen@xxxxxxxxxx> wrote:

> Ingo Molnar wrote:
>
> >But, because you assert it that it's risky to "criticise sched_yield()
> >too much", you sure must know at least one real example where it's right
> >to use it (and cite the line and code where it's used, with
> >specificity)?
>
> It's fine to criticise sched_yield(). I agree that new apps should
> generally be written to use proper completion mechanisms or to wait
> for specific events.

yes.

> However, there are closed-source and/or frozen-source apps where it's
> not practical to rewrite or rebuild the app. Does it make sense to
> break the behaviour of all of these?

See the background and answers to that in:

http://lkml.org/lkml/2007/9/19/357
http://lkml.org/lkml/2007/9/19/328

there's plenty of recourse possible to all possible kinds of apps. Tune
the sysctl flag in one direction or another, depending on which behavior
the app is expecting.

Ingo
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