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SubjectRe: [RFC] Fair-user scheduler
Srivatsa Vaddagiri wrote:
> Current Linux CPU scheduler doesnt recognize process aggregates while
> allocating bandwidth. As a result of this, an user could simply spawn large
> number of processes and get more bandwidth than others.
>
> Here's a patch that provides fair allocation for all users in a system.
>
> Some benchmark numbers with and without the patch applied follows:
>
>
> user "vatsa" user "guest"
> (make -s -j4 bzImage) (make -s -j20 bzImage)
>
> 2.6.20-rc5 472.07s (real) 257.48s (real)
> 2.6.20-rc5+fairsched 766.74s (real) 766.73s (real)

As Kirill brought up, why does it take so much more time? Are you
thrashing the cache?

> - breaks O(1) (ouch!)
> Best way to avoid this is to split runqueue to be per-user and
> per-cpu, which I have not implemented to keep the patch simple.

Presumably this would be made generic, as in per-"group" rather than per
user?

> - Fairsched aware SMP load balance NOT addressed (yet)

This is kind of important, no?

Chris
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