From: Thomas Gleixner <tglx@linutronix.de>
To: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Alexey Dobriyan <adobriyan@gmail.com>,
Tatsiana Brouka <Tatsiana_Brouka@epam.com>,
linux-kernel@vger.kernel.org, linux-api@vger.kernel.org,
Aliaksandr Patseyenak <Aliaksandr_Patseyenak1@epam.com>
Subject: Re: [PATCH 1/2] pidmap(2)
Date: Wed, 6 Sep 2017 10:30:04 +0200 (CEST) [thread overview]
Message-ID: <alpine.DEB.2.20.1709061029270.1843@nanos> (raw)
In-Reply-To: <d538b917-3e3e-827c-7ca0-5493961cf6f1@infradead.org>
On Tue, 5 Sep 2017, Randy Dunlap wrote:
> On 09/05/17 15:53, Andrew Morton wrote:
> > On Tue, 5 Sep 2017 22:05:00 +0300 Alexey Dobriyan <adobriyan@gmail.com> wrote:
> >
> >> Implement system call for bulk retrieveing of pids in binary form.
> >>
> >> Using /proc is slower than necessary: 3 syscalls + another 3 for each thread +
> >> converting with atoi().
> >>
> >> /proc may be not mounted especially in containers. Natural extension of
> >> hidepid=2 efforts is to not mount /proc at all.
> >>
> >> It could be used by programs like ps, top or CRIU. Speed increase will
> >> become more drastic once combined with bulk retrieval of process statistics.
> >
> > The patches are performance optimizations, but their changelogs contain
> > no performance measurements!
> >
> > Demonstration of some compelling real-world performance benefits would
> > help things along a lot.
> >
>
> also, I expect that the tiny kernel people will want kconfig options for
> these syscalls.
And of course that stuff wants the corresponding man pages written up.
Thanks,
tglx
next prev parent reply other threads:[~2017-09-06 8:30 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-09-05 19:05 Alexey Dobriyan
2017-09-05 19:06 ` [PATCH 2/2] fdmap(2) Alexey Dobriyan
2017-09-05 22:53 ` [PATCH 1/2] pidmap(2) Andrew Morton
2017-09-05 23:02 ` Randy Dunlap
2017-09-06 8:30 ` Thomas Gleixner [this message]
2017-09-06 9:04 ` Alexey Dobriyan
2017-09-07 2:04 ` Andy Lutomirski
2017-09-07 5:06 ` Djalal Harouni
2017-09-07 9:47 ` Alexey Dobriyan
2017-09-07 9:43 ` Alexey Dobriyan
2017-09-06 8:55 ` Alexey Dobriyan
2017-09-07 10:08 ` Dmitry V. Levin
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=alpine.DEB.2.20.1709061029270.1843@nanos \
--to=tglx@linutronix.de \
--cc=Aliaksandr_Patseyenak1@epam.com \
--cc=Tatsiana_Brouka@epam.com \
--cc=adobriyan@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=linux-api@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=rdunlap@infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®