All of lore.kernel.org
 help / color / mirror / Atom feed
From: Tejun Heo <tj@kernel.org>
To: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Oleg Nesterov <oleg@redhat.com>,
	Roland McGrath <roland@redhat.com>,
	jan.kratochvil@redhat.com, linux-kernel@vger.kernel.org,
	torvalds@linux-foundation.org, akpm@linux-foundation.org
Subject: Re: [RFC] Proposal for ptrace improvements
Date: Fri, 4 Mar 2011 15:40:59 +0100	[thread overview]
Message-ID: <20110304144059.GS20499@htj.dyndns.org> (raw)
In-Reply-To: <AANLkTina7D3QffUK7vYvc3aVTvbcJQqm8VgQP3xJKYdw@mail.gmail.com>

On Fri, Mar 04, 2011 at 03:31:15PM +0100, Denys Vlasenko wrote:
> On Fri, Mar 4, 2011 at 3:07 PM, Tejun Heo <tj@kernel.org> wrote:
> > Hello,
> >
> > On Fri, Mar 04, 2011 at 02:59:32PM +0100, Denys Vlasenko wrote:
> >> I would rather speed strace up than slow it down further, even if
> >> slightly.
> >
> > The question to ask is at what cost?  If mostly unnoticeable slow down
> > makes the API cleaner, I'll go that way.  Everything is a tradeoff.
> 
> # time sh -c 'ls -lR /usr/share >/dev/null'
> real	0m2.633s
>
> strace without PTRACE_GETSIGINFO:
> real	0m47.023s
> real	0m48.799s
> real	0m47.695s
>
> strace with PTRACE_GETSIGINFO:
> real	0m51.958s
> real	0m53.773s
> real	0m51.625s

Great, numbers, so it's ~10 slow down.  Gees, with or without that
change, strace(2) is heavy, >18 times slower than without.  Maybe it
should give up on ptrace and use the new tracing infrastructure?

Anyways, thanks a lot for the numbers.  Much appreciated.

-- 
tejun

  reply	other threads:[~2011-03-04 14:41 UTC|newest]

Thread overview: 73+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-03-01 15:24 [RFC] Proposal for ptrace improvements Tejun Heo
2011-03-01 16:57 ` Denys Vlasenko
2011-03-01 17:09   ` Tejun Heo
2011-03-01 17:12     ` Tejun Heo
2011-03-01 17:21     ` Denys Vlasenko
2011-03-01 18:34       ` Tejun Heo
2011-03-01 23:51         ` Denys Vlasenko
2011-03-02  7:10           ` Tejun Heo
2011-03-02  5:07         ` Indan Zupancic
2011-03-02  7:44           ` Tejun Heo
2011-03-02 11:32             ` Indan Zupancic
2011-03-02 11:52               ` Denys Vlasenko
2011-03-02 14:50               ` Tejun Heo
2011-03-02 13:32             ` Oleg Nesterov
2011-03-03  0:47               ` Indan Zupancic
2011-03-03  1:30                 ` Denys Vlasenko
2011-03-03  1:55                   ` Indan Zupancic
2011-03-03  7:03                     ` Tejun Heo
2011-03-01 19:06 ` Jan Kratochvil
2011-03-01 22:14   ` Denys Vlasenko
2011-03-02  7:28     ` Tejun Heo
2011-03-02 10:58       ` Denys Vlasenko
2011-03-04 16:14     ` Jan Kratochvil
2011-03-04 16:41       ` Denys Vlasenko
2011-03-04 17:07       ` Oleg Nesterov
2011-03-04 18:12         ` Jan Kratochvil
2011-03-05  8:47           ` Tejun Heo
2011-03-01 22:59 ` Denys Vlasenko
2011-03-02  7:32   ` Tejun Heo
2011-03-02 11:02     ` Denys Vlasenko
2011-03-02 11:23       ` Tejun Heo
2011-03-03 19:26         ` Oleg Nesterov
2011-03-01 23:16 ` Denys Vlasenko
2011-03-02  7:37   ` Tejun Heo
2011-03-02 11:21     ` Denys Vlasenko
2011-03-02 11:27       ` Tejun Heo
2011-03-02 11:48         ` Denys Vlasenko
2011-03-02 14:43           ` Tejun Heo
2011-03-02 15:16             ` Denys Vlasenko
2011-03-02 15:25               ` Tejun Heo
2011-03-03 17:34 ` Oleg Nesterov
2011-03-03 20:22   ` Oleg Nesterov
2011-03-04  8:23     ` Tejun Heo
2011-03-04 18:16       ` Oleg Nesterov
2011-03-05  8:33         ` Tejun Heo
2011-03-04 13:01     ` Denys Vlasenko
2011-03-04 13:41       ` Tejun Heo
2011-03-04 13:59         ` Denys Vlasenko
2011-03-04 14:07           ` Tejun Heo
2011-03-04 14:31             ` Denys Vlasenko
2011-03-04 14:40               ` Tejun Heo [this message]
2011-03-04 17:05                 ` Denys Vlasenko
2011-03-04 17:12                   ` Linus Torvalds
2011-03-04 18:59                     ` Denys Vlasenko
2011-03-04 19:24                       ` Linus Torvalds
2011-03-04 16:13               ` Oleg Nesterov
2011-03-04 16:30                 ` Oleg Nesterov
2011-03-04  8:44   ` Tejun Heo
2011-03-04 16:01     ` Oleg Nesterov
2011-03-04 16:15       ` Tejun Heo
2011-03-04 16:26         ` Oleg Nesterov
2011-03-07 15:08 ` PTRACE_SEIZE/INTERRUPT: " Oleg Nesterov
2011-03-09  9:41   ` Tejun Heo
2011-03-09 17:30     ` Oleg Nesterov
2011-03-07 20:43 ` Roland McGrath
2011-03-09 10:28   ` Tejun Heo
2011-03-10 18:33     ` Steven Rostedt
2011-03-11  8:13       ` Tejun Heo
2011-03-11  8:22       ` Ingo Molnar
2011-03-11  9:35         ` Srikar Dronamraju
2011-03-11  9:43           ` Ingo Molnar
2011-03-14  1:03     ` Frank Ch. Eigler
2011-03-10 15:55   ` Steven Rostedt

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=20110304144059.GS20499@htj.dyndns.org \
    --to=tj@kernel.org \
    --cc=akpm@linux-foundation.org \
    --cc=jan.kratochvil@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=oleg@redhat.com \
    --cc=roland@redhat.com \
    --cc=torvalds@linux-foundation.org \
    --cc=vda.linux@googlemail.com \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.