From: Lin Ming <ming.m.lin@intel.com>
To: peterz@infradead.org
Cc: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>,
linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: hackbench [pthread mode] regression with 2.6.29-rc3
Date: Sun, 01 Feb 2009 16:29:21 +0800 [thread overview]
Message-ID: <1233476961.13659.12.camel@minggr.sh.intel.com> (raw)
In-Reply-To: <d3f22a0902010026q1db36381j36cb1c9803d48431@mail.gmail.com>
> Bisect located below patch.
> commit 490dea45d00f01847ebebd007685d564aaf2cd98
> Author: Peter Zijlstra <peterz@infradead.org>
> Date: Mon Nov 24 17:06:57 2008 +0100
>
> itimers: remove the per-cpu-ish-ness
>
> Either we bounce once cacheline per cpu per tick, yielding n^2 bounces
> or we just bounce a single..
>
> Also, using per-cpu allocations for the thread-groups complicates the
> per-cpu allocator in that its currently aimed to be a fixed sized
> allocator and the only possible extention to that would be vmap based,
> which is seriously constrained on 32 bit archs.
>
>
> After above patch is reverted, hackbench result is restored.
oltp has ~3% regression with 2.6.29-rc3 on 4core*2p stokley machine.
After above patch reverted, the regression disappeared.
Lin Ming
next prev parent reply other threads:[~2009-02-01 8:32 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-02-01 7:30 Zhang, Yanmin
[not found] ` <d3f22a0902010026q1db36381j36cb1c9803d48431@mail.gmail.com>
2009-02-01 8:29 ` Lin Ming [this message]
2009-02-01 9:17 ` Peter Zijlstra
2009-02-01 9:57 ` Peter Zijlstra
2009-02-01 10:04 ` Ingo Molnar
2009-02-02 1:12 ` Zhang, Yanmin
2009-02-02 8:53 ` Peter Zijlstra
2009-02-02 17:49 ` Bryon Roche
2009-02-02 20:50 ` Peter Zijlstra
2009-02-03 11:56 ` [RFC] process wide itimer cruft Peter Zijlstra
2009-02-03 17:23 ` Oleg Nesterov
2009-02-03 17:51 ` Peter Zijlstra
2009-02-03 18:22 ` Oleg Nesterov
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=1233476961.13659.12.camel@minggr.sh.intel.com \
--to=ming.m.lin@intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=peterz@infradead.org \
--cc=yanmin_zhang@linux.intel.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 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®