Re: [PATCH v2 0/2] Replace PID bitmap allocation with IDR API

Rik van Riel
2017-09-29T00:35:34Z

[-- Attachment #1: Type: text/plain, Size: 1440 bytes --]

On Fri, 2017-09-29 at 01:35 +0530, Gargi Sharma wrote:
> On Thu, Sep 28, 2017 at 3:46 PM, Rik van Riel <riel@surriel.com>
> wrote:
> > On Fri, 2017-09-29 at 01:09 +0530, Gargi Sharma wrote:
> >
> > > 1000 processes that just sleep and sit around without doing
> > > anything(100 second sleep and then exit).
> >
> > Is that with or without your patches?
> >
> > How does it compare to a kernel with(out) your patches?
>
> Ah thanks for pointing this out. Those were without the patches.
> Here are the stats for easier comparison.
>
> With Patches                 Without patches
> pstree
> real    0m0.542s            real    0m0.859s
> user    0m0.335s           user    0m0.536s
> sys    0m0.150s             sys    0m0.172s
>
> ps
> real    0m0.722s            real    0m0.918s
> user    0m0.064s           user    0m0.100s
> sys    0m0.162s             sys    0m0.172s
>
> readdir
> real    0m0.080s           real    0m0.092s
> user    0m0.000s          user    0m0.000s
> sys    0m0.021s            sys    0m0.020s

So your patches speed up the use of /proc?

I suspect pstree and ps benefit from the simplification
and speedup of find_pid_ns, which is called from
find_task_by_pid_ns.

That is great news.

--
All Rights Reversed.

[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 473 bytes --]