Re: REGRESSION: Performance regressions from switching anon_vma->lock to mutex

Peter Zijlstra
2011-06-15T21:38:37Z

On Wed, 2011-06-15 at 14:12 -0700, Tim Chen wrote:
> Thanks to Andi for providing the info. We've used this workaround in
> our testing so it will not mask true kernel scaling bottlenecks.

http://programming.kicks-ass.net/sekrit/39-2.txt.bz2
http://programming.kicks-ass.net/sekrit/tip-2.txt.bz2

tip+sirq+linus is still slightly faster than .39 here, although removing
that sysconf() wreckage closed the gap considerably (needing to know the
number of cpus to optimize locking sounds like a trainwreck all of its
own, needing it _that_ often instead of just once at startup is even
worse).