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

Andi Kleen
2011-06-16T22:00:41Z

> Ok, I bet it doesn't make them a non-issue, but if doing this in
> anon_vma_clone() helped a lot, then doing the exact same pattern in
> unlink_anon_vmas() hopefully helps some more.
Hi Linus,

I did essentially the same thing (just in a less elegant, more paranoid
way) in my old
batching patches.

http://comments.gmane.org/gmane.linux.kernel.mm/63130

They made it a bit better, but overall it's still much worse than 2.6.35
(.36 introduced the
root chain locking). I guess we'll see if it can recover mutex though,
but I'm not
optimistic.

-Andi