Re: [patch] CFS scheduler, v3

[Siddha, Suresh B]

On Tue, Apr 24, 2007 at 10:47:45AM -0700, Christoph Lameter wrote:
> On Tue, 24 Apr 2007, Siddha, Suresh B wrote:
> > Anyhow, this is a straight forward optimization and needs to be done. Do you
> > have any specific concerns?
> 
> Yes there should not be contention on per cpu data in principle. The 
> point of per cpu data is for the cpu to have access to contention free 
> cachelines.
> 
> If the data is contented then it should be moved out of per cpu data and properly 
> placed to minimize contention. Otherwise we will get into cacheline 
> aliases (__read_mostly in per cpu??) etc etc in the per cpu areas.

yes, we were planning to move this to a different percpu section, where
all the elements in this new section will be cacheline aligned(both
at the start, aswell as end)

thanks,
suresh
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