All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
To: Christoph Lameter <cl@linux-foundation.org>
Cc: Tejun Heo <tj@kernel.org>, Pekka Enberg <penberg@cs.helsinki.fi>,
	alex.shi@intel.com,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"Ma, Ling" <ling.ma@intel.com>,
	"Chen, Tim C" <tim.c.chen@intel.com>,
	Andrew Morton <akpm@linux-foundation.org>
Subject: Re: hackbench regression due to commit 9dfc6e68bfe6e
Date: Wed, 07 Apr 2010 10:20:40 +0800	[thread overview]
Message-ID: <1270606840.2078.231.camel@ymzhang.sh.intel.com> (raw)
In-Reply-To: <alpine.DEB.2.00.1004061552500.19151@router.home>

On Tue, 2010-04-06 at 15:55 -0500, Christoph Lameter wrote:
> We cannot reproduce the issue here. Our tests here (dual quad dell) show a
> performance increase in hackbench instead.
I run hackbench on many machines. The regression exists on Nehalem machine
(dual sockets, 2*4*2 logical cpu) and a tigerton (4 socket, 4*4 logical cpu)
machines. I tried it on a dual quad core2 machine and it does like what you said.

The regression also exists on 2 new-generation Nehalem (dual socket 2*6*2 logical cpu)
machines.

It seems hyperthreading cpu has more chances to trigger it.

> 
> Linux 2.6.33.2 #2 SMP Mon Apr 5 11:30:56 CDT 2010 x86_64 GNU/Linux
> ./hackbench 100 process 200000
> Running with 100*40 (== 4000) tasks.
> Time: 3102.142
> ./hackbench 100 process 20000
> Running with 100*40 (== 4000) tasks.
> Time: 308.731
> ./hackbench 100 process 20000
> Running with 100*40 (== 4000) tasks.
> Time: 311.591
> ./hackbench 100 process 20000
> Running with 100*40 (== 4000) tasks.
> Time: 310.200
> ./hackbench 10 process 20000
> Running with 10*40 (== 400) tasks.
> Time: 38.048
> ./hackbench 10 process 20000
> Running with 10*40 (== 400) tasks.
> Time: 44.711
> ./hackbench 10 process 20000
> Running with 10*40 (== 400) tasks.
> Time: 39.407
> ./hackbench 1 process 20000
> Running with 1*40 (== 40) tasks.
> Time: 9.411
> ./hackbench 1 process 20000
> Running with 1*40 (== 40) tasks.
> Time: 8.765
> ./hackbench 1 process 20000
> Running with 1*40 (== 40) tasks.
> Time: 8.822
> 
> Linux 2.6.34-rc3 #1 SMP Tue Apr 6 13:30:34 CDT 2010 x86_64 GNU/Linux
> ./hackbench 100 process 200000
> Running with 100*40 (== 4000) tasks.
> Time: 3003.578
> ./hackbench 100 process 20000
> Running with 100*40 (== 4000) tasks.
> Time: 300.289
> ./hackbench 100 process 20000
> Running with 100*40 (== 4000) tasks.
> Time: 301.462
> ./hackbench 100 process 20000
> Running with 100*40 (== 4000) tasks.
> Time: 301.173
> ./hackbench 10 process 20000
> Running with 10*40 (== 400) tasks.
> Time: 41.191
> ./hackbench 10 process 20000
> Running with 10*40 (== 400) tasks.
> Time: 41.964
> ./hackbench 10 process 20000
> Running with 10*40 (== 400) tasks.
> Time: 41.470
> ./hackbench 1 process 20000
> Running with 1*40 (== 40) tasks.
> Time: 8.829
> ./hackbench 1 process 20000
> Running with 1*40 (== 40) tasks.
> Time: 9.166
> ./hackbench 1 process 20000
> Running with 1*40 (== 40) tasks.
> Time: 8.681
> 
> 



  parent reply	other threads:[~2010-04-07  2:18 UTC|newest]

Thread overview: 43+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-03-25  8:40 hackbench regression due to commit 9dfc6e68bfe6e Alex Shi
2010-03-25 14:49 ` Christoph Lameter
2010-03-26  2:35   ` Alex Shi
2010-04-01  9:29     ` Zhang, Yanmin
2010-04-01 15:53       ` Christoph Lameter
2010-04-02  8:06         ` Zhang, Yanmin
2010-04-05 13:54           ` Christoph Lameter
2010-04-05 17:30             ` Pekka Enberg
2010-04-06  1:27               ` Tejun Heo
2010-04-06  8:28                 ` Zhang, Yanmin
2010-04-06 15:41                   ` Christoph Lameter
2010-04-06 20:55                     ` Christoph Lameter
2010-04-06 22:10                       ` Eric Dumazet
2010-04-07  2:34                         ` Zhang, Yanmin
2010-04-07  6:39                           ` Eric Dumazet
2010-04-07  9:07                             ` Zhang, Yanmin
2010-04-07  9:20                               ` Eric Dumazet
2010-04-07 10:47                           ` Pekka Enberg
2010-04-07 16:30                           ` Christoph Lameter
2010-04-07 16:43                           ` Christoph Lameter
2010-04-07 16:49                             ` Pekka Enberg
2010-04-07 16:52                               ` Pekka Enberg
2010-04-07 18:20                                 ` Christoph Lameter
2010-04-07 18:25                                   ` Pekka Enberg
2010-04-07 18:25                                     ` Pekka Enberg
2010-04-07 19:30                                     ` Christoph Lameter
2010-04-07 18:38                                   ` Eric Dumazet
2010-04-08  1:05                                     ` Zhang, Yanmin
2010-04-08  4:59                                       ` Eric Dumazet
2010-04-08  5:39                                         ` Eric Dumazet
2010-04-08  7:00                                           ` Eric Dumazet
2010-04-08  7:05                                             ` David Miller
2010-04-08  7:20                                               ` David Miller
2010-04-08  7:25                                               ` Eric Dumazet
2010-04-08  7:54                                             ` Zhang, Yanmin
2010-04-08  7:54                                               ` Eric Dumazet
2010-04-08  8:09                                                 ` Eric Dumazet
2010-04-08 15:34                                           ` Christoph Lameter
2010-04-08 15:52                                             ` Eric Dumazet
2010-04-07 18:18                               ` Christoph Lameter
2010-04-08  7:18                             ` Zhang, Yanmin
2010-04-07  2:20                       ` Zhang, Yanmin [this message]
2010-04-07  0:58                     ` Zhang, Yanmin

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=1270606840.2078.231.camel@ymzhang.sh.intel.com \
    --to=yanmin_zhang@linux.intel.com \
    --cc=akpm@linux-foundation.org \
    --cc=alex.shi@intel.com \
    --cc=cl@linux-foundation.org \
    --cc=ling.ma@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=penberg@cs.helsinki.fi \
    --cc=tim.c.chen@intel.com \
    --cc=tj@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.