Re: [RFC] CPU hard limits

Avi Kivity
2009-06-05T06:05:52Z

Balbir Singh wrote:
>> I think so. Given guarantees G1..Gn (0 <= Gi <= 1; sum(Gi) <= 1), and a
>> cpu hog running in each group, how would the algorithm divide resources?
>>
>>
>
> As per the matrix calculation, but as soon as we reach an idle point,
> we redistribute the b/w and start a new quantum so to speak, where all
> groups are charged up to their hard limits.
>
> For your question, if there is a CPU hog running, it would be as per
> the matrix calculation, since the system has no idle point during the
> bandwidth period.
>

So the groups with guarantees get a priority boost. That's not a good
side effect.

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