From: Arnd Bergmann <arnd@arndb.de>
To: linuxppc-dev@ozlabs.org
Subject: Re: 82xx performance
Date: Mon, 14 Jul 2008 22:44:07 +0200 [thread overview]
Message-ID: <200807142244.07450.arnd@arndb.de> (raw)
In-Reply-To: <DCEAAC0833DD314AB0B58112AD99B93B04AE61BC@ismail.innsys.innovsys.com>
On Monday 14 July 2008, Rune Torgersen wrote:
> Context switching - times in microseconds - smaller is better
> ------------------------------------------------------------------------
> Host OS 2p/0K 2p/16K 2p/64K 8p/16K 8p/64K 16p/16K 16p/64K
> ctxsw ctxsw ctxsw ctxsw ctxsw ctxsw ctxsw
> --------- ------------- ------ ------ ------ ------ ------ ------- -------
> 9919_unit Linux 2.6.25 20.6 86.2 28.5 103.8 38.7 111.8 57.4
> 9919_unit Linux 2.6.18 5.3300 63.2 17.9 73.4 23.1 74.9 26.2
This is certainly significant, but a lot has happened between the two
versions. I few ideas:
* compare some of the key configuration options:
# CONFIG_DEBUG_*
# CONFIG_PREEMPT*
# CONFIG_NO_HZ
# CONFIG_HZ
* Try looking at where the time is spent, using oprofile or readprofile
* Try setting /proc/sys/kernel/compat/sched_yield to 1, to get the legacy
behaviour of the scheduler.
* Maybe there is a kernel version that supports your hardware in both
arch/ppc/ and arch/powerpc. In that case, you could see if the platform
change had an impact.
Arnd <><
next prev parent reply other threads:[~2008-07-14 20:44 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-07-14 16:34 82xx performance Rune Torgersen
2008-07-14 20:44 ` Arnd Bergmann [this message]
2008-07-15 14:16 ` Rune Torgersen
2008-07-15 18:25 ` Rune Torgersen
2008-07-15 19:50 ` Arnd Bergmann
2008-07-16 21:08 ` Rune Torgersen
2008-07-16 21:45 ` Arnd Bergmann
2008-07-16 21:53 ` Rune Torgersen
2008-07-16 22:32 ` Arnd Bergmann
2008-07-17 15:12 ` Rune Torgersen
2008-07-17 15:47 ` Arnd Bergmann
2008-07-17 15:52 ` Rune Torgersen
2008-07-17 18:24 ` Rune Torgersen
2008-07-17 19:43 ` Arnd Bergmann
2008-07-17 19:54 ` Rune Torgersen
2008-07-17 21:32 ` Arnd Bergmann
2008-07-25 20:41 ` Rune Torgersen
2008-07-26 3:47 ` Milton Miller
2008-07-15 15:57 ` Milton Miller
2008-07-15 18:12 ` Rune Torgersen
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