From: Ingo Molnar <mingo@elte.hu>
To: Jie Chen <chen@jlab.org>
Cc: linux-kernel@vger.kernel.org, Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: Re: Possible bug from kernel 2.6.22 and above, 2.6.24-rc4
Date: Tue, 11 Dec 2007 22:23:52 +0100 [thread overview]
Message-ID: <20071211212352.GF6902@elte.hu> (raw)
In-Reply-To: <475EBD30.1010506@jlab.org>
* Jie Chen <chen@jlab.org> wrote:
> The following is pthread_sync output for 2.6.21.7-cfs-v24 #1 SMP
> kernel.
> 2 threads:
> PARALLEL time = 11.106580 microseconds +/- 0.002460
> PARALLEL overhead = 0.617590 microseconds +/- 0.003409
> Output for Kernel 2.6.24-rc4 #1 SMP
> PARALLEL time = 19.668450 microseconds +/- 0.015782
> PARALLEL overhead = 9.157945 microseconds +/- 0.018217
ok, so the problem is that this PARALLEL time has an additional +9 usecs
overhead, right? I dont see this myself on a Core2 CPU:
PARALLEL time = 10.446933 microseconds +/- 0.078849
PARALLEL overhead = 0.751732 microseconds +/- 0.177446
Ingo
next prev parent reply other threads:[~2007-12-11 21:24 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-11-21 20:34 Possible bug from kernel 2.6.22 and above Jie Chen
2007-11-21 22:14 ` Eric Dumazet
2007-11-22 1:52 ` Jie Chen
2007-11-22 2:32 ` Simon Holm Thøgersen
2007-11-22 2:58 ` Jie Chen
2007-11-22 20:19 ` Matt Mackall
2007-12-04 13:17 ` Possible bug from kernel 2.6.22 and above, 2.6.24-rc4 Ingo Molnar
2007-12-04 15:41 ` Jie Chen
2007-12-05 15:29 ` Jie Chen
2007-12-05 15:40 ` Ingo Molnar
2007-12-05 16:16 ` Eric Dumazet
2007-12-05 16:25 ` Ingo Molnar
2007-12-05 16:29 ` Eric Dumazet
2007-12-05 16:22 ` Jie Chen
2007-12-05 16:47 ` Ingo Molnar
2007-12-05 17:47 ` Jie Chen
2007-12-05 20:03 ` Ingo Molnar
2007-12-05 20:23 ` Jie Chen
2007-12-05 20:46 ` Ingo Molnar
2007-12-05 20:52 ` Jie Chen
2007-12-05 21:02 ` Ingo Molnar
2007-12-05 22:16 ` Jie Chen
2007-12-06 10:43 ` Ingo Molnar
2007-12-06 16:29 ` Jie Chen
2007-12-10 10:59 ` Ingo Molnar
2007-12-10 20:04 ` Jie Chen
2007-12-11 10:51 ` Ingo Molnar
2007-12-11 15:28 ` Jie Chen
2007-12-11 15:52 ` Ingo Molnar
2007-12-11 16:39 ` Jie Chen
2007-12-11 21:23 ` Ingo Molnar [this message]
2007-12-11 22:11 ` Jie Chen
2007-12-12 12:49 ` Peter Zijlstra
2007-12-05 20:36 ` Possible bug from kernel 2.6.22 and above Peter Zijlstra
2007-12-05 20:53 ` Jie Chen
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=20071211212352.GF6902@elte.hu \
--to=mingo@elte.hu \
--cc=a.p.zijlstra@chello.nl \
--cc=chen@jlab.org \
--cc=linux-kernel@vger.kernel.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 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.