Re: [PATCH] MM: implement MADV_FREE lazy freeing of anonymous memory

Ulrich Drepper
2007-05-04T16:05:11Z

[-- Attachment #1: Type: text/plain, Size: 835 bytes --]

Nick Piggin wrote:
> What I found is that, on this system, MADV_FREE performance improvement
> was in the noise when you look at it on top of the MADV_DONTNEED glibc
> and down_read(mmap_sem) patch in sysbench.

I don't want to judge the numbers since I cannot but I want to make an
observations: even if in the SMP case MADV_FREE turns out to not be a
bigger boost then there is still the UP case to keep in mind where Rik
measured a significant speed-up. As long as the SMP case isn't hurt
this is reaosn enough to use the patch. With more and more cores on one
processor SMP systems are pushed evermore to the high-end side. You'll
find many installations which today use SMP will be happy enough with
many-core UP machines.

--
➧ Ulrich Drepper ➧ Red Hat, Inc. ➧ 444 Castro St ➧ Mountain View, CA ❖

[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 251 bytes --]