[lkml]   [2011]   [Oct]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH] Reduce vm_stat cacheline contention in __vm_enough_memory
On Thu, 13 Oct 2011, Andrew Morton wrote:

> > If there are no updates occurring for a while (due to increased deltas
> > and/or vmstat updates) then the vm_stat cacheline should be able to stay
> > in shared mode in multiple processors and the performance should increase.
> >
> We could cacheline align vm_stat[]. But the thing is pretty small - we
> couild put each entry in its own cacheline.

Which in turn would increase the cache footprint of some key kernel
functions (because they need multiple vm_stat entries) and cause eviction
of other cachelines that then reduce overall system performance again.

 \ /
  Last update: 2011-10-13 23:05    [W:0.067 / U:0.492 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site