lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <1308138091.15315.50.camel@twins>
Date:	Wed, 15 Jun 2011 13:41:31 +0200
From:	Peter Zijlstra <peterz@...radead.org>
To:	Tim Chen <tim.c.chen@...ux.intel.com>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Hugh Dickins <hughd@...gle.com>,
	KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>,
	Benjamin Herrenschmidt <benh@...nel.crashing.org>,
	David Miller <davem@...emloft.net>,
	Martin Schwidefsky <schwidefsky@...ibm.com>,
	Russell King <rmk@....linux.org.uk>,
	Paul Mundt <lethal@...ux-sh.org>,
	Jeff Dike <jdike@...toit.com>,
	Richard Weinberger <richard@....at>,
	Tony Luck <tony.luck@...el.com>,
	KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>,
	Mel Gorman <mel@....ul.ie>, Nick Piggin <npiggin@...nel.dk>,
	Namhyung Kim <namhyung@...il.com>, ak@...ux.intel.com,
	shaohua.li@...el.com, alex.shi@...el.com,
	linux-kernel@...r.kernel.org, linux-mm@...ck.org,
	"Rafael J. Wysocki" <rjw@...k.pl>,
	paulmck <paulmck@...ux.vnet.ibm.com>
Subject: Re: REGRESSION: Performance regressions from switching
 anon_vma->lock to mutex

On Wed, 2011-06-15 at 12:58 +0200, Peter Zijlstra wrote:
> On Wed, 2011-06-15 at 12:36 +0200, Peter Zijlstra wrote:
> > On Tue, 2011-06-14 at 17:29 -0700, Tim Chen wrote:
> > > MOSBENCH test suite.
> > 
> > Argh, I'm trying to get this thing to run, but its all snake poo..
> > 
> > /me takes up a heavy club and goes snake hunting, should make a pretty
> > hat or something.
> 
> Sweet, I've got meself a snake-skin hat!
> 
> The first thing that stood out when running it was:
> 
> 31694 root      20   0 26660 1460 1212 S 17.5  0.0   0:01.97 exim 
>     7 root      -2  19     0    0    0 S 12.7  0.0   0:06.14 rcuc0 
>    24 root      -2  19     0    0    0 S 11.7  0.0   0:04.15 rcuc3 
>    34 root      -2  19     0    0    0 S 11.7  0.0   0:04.10 rcuc5 
>    39 root      -2  19     0    0    0 S 11.7  0.0   0:06.38 rcuc6 
>    44 root      -2  19     0    0    0 S 11.7  0.0   0:04.53 rcuc7 
>    49 root      -2  19     0    0    0 S 11.7  0.0   0:04.11 rcuc8 
>    79 root      -2  19     0    0    0 S 11.7  0.0   0:03.91 rcuc14 
>    89 root      -2  19     0    0    0 S 11.7  0.0   0:03.90 rcuc16 
>   110 root      -2  19     0    0    0 S 11.7  0.0   0:03.90 rcuc20 
>   120 root      -2  19     0    0    0 S 11.7  0.0   0:03.82 rcuc22 
>    13 root      -2  19     0    0    0 S 10.7  0.0   0:04.37 rcuc1 
>    19 root      -2  19     0    0    0 S 10.7  0.0   0:04.19 rcuc2 
>    29 root      -2  19     0    0    0 S 10.7  0.0   0:04.12 rcuc4 
>    54 root      -2  19     0    0    0 S 10.7  0.0   0:04.11 rcuc9 
>    59 root      -2  19     0    0    0 S 10.7  0.0   0:04.40 rcuc10 
>    64 root      -2  19     0    0    0 R 10.7  0.0   0:04.17 rcuc11 
>    69 root      -2  19     0    0    0 R 10.7  0.0   0:04.23 rcuc12 
>    84 root      -2  19     0    0    0 S 10.7  0.0   0:03.90 rcuc15 
>    95 root      -2  19     0    0    0 S 10.7  0.0   0:03.99 rcuc17 
>   100 root      -2  19     0    0    0 S 10.7  0.0   0:03.88 rcuc18 
>   105 root      -2  19     0    0    0 S 10.7  0.0   0:04.14 rcuc19 
>   125 root      -2  19     0    0    0 S 10.7  0.0   0:03.79 rcuc23 
>    74 root      -2  19     0    0    0 S  9.7  0.0   0:04.33 rcuc13 
>   115 root      -2  19     0    0    0 R  9.7  0.0   0:03.82 rcuc21 
> 
> Which is an impressive amount of RCU usage..

FWIW, Alex Shi's patch:

http://lkml.kernel.org/r/1308029185.15392.147.camel@sli10-conroe

Improves the situation to:

 3745 root      20   0 26664 1460 1212 S 18.5  0.0   0:01.28 exim 
   39 root      -2  19     0    0    0 S  4.9  0.0   0:02.83 rcuc6 
  105 root      -2  19     0    0    0 S  4.9  0.0   0:02.79 rcuc19 
    7 root      -2  19     0    0    0 S  3.9  0.0   0:02.70 rcuc0 
   13 root      -2  19     0    0    0 S  3.9  0.0   0:02.54 rcuc1 
   19 root      -2  19     0    0    0 S  3.9  0.0   0:02.76 rcuc2 
   24 root      -2  19     0    0    0 S  3.9  0.0   0:02.75 rcuc3 
...

And throughput increases like:

-tip            260.092 messages/sec/core
-tip+sirq-rcu   271.078 messages/sec/core


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ