Re: [RFC] CPU hard limits

[Avi Kivity <avi@redhat.com>]

Chris Friesen wrote:
> Avi Kivity wrote:
>
>   
>> I am selling virtual private servers.  A 10% cpu share costs $x/month, 
>> and I guarantee you'll get that 10%, or your money back.  On the other 
>> hand, I want to limit cpu usage to that 10% (maybe a little more) so 
>> people don't buy 10% shares and use 100% on my underutilized servers.  
>> If they want 100%, let them pay for 100%.
>>     
>
> What about taking a page from the networking folks and specifying cpu
> like a networking SLA?
>
> Something like "group A is guaranteed X percent (or share) of the cpu,
> but it is allowed to burst up to Y percent for Z milliseconds"
>
> If a rule of this form was the first-class citizen, it would provide
> both guarantees, limits, and flexible behaviour.
>   

I think you're introducing a new control (guarantees, limits, burst 
limit), but I like it.

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.