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

Linus Torvalds
2011-06-15T21:52:05Z

Peter Zijlstra <a.p.zijlstra@chello.nl> wrote:
>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).

Yeah, I think it's ridiculous to say that glibc is not doing something stupid and that it's a problem with kernel interfaces.

Do the proc file parsing once and cache the result in a static variable. Doing it over and over again is just crazy.

Adding new system calls because glibc is crazy is insane.

Linus