lkml.org 
[lkml]   [2008]   [Mar]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: 2.6.25-rc4-git3: Reported regressions from 2.6.24
From
Date
On Mon, 2008-03-10 at 01:32 +0100, Rafael J. Wysocki wrote:
> [Due to the lack of time for reviewing all of the email threads related to the
> regressions marked as "unresolved" below, I might have missed some patches
> fixing them. If you are involved in debugging/fixing any of them, please let
> me know if I should update the list. Thanks!]
>
> This message contains a list of some regressions from 2.6.24 reported since
> 2.6.25-rc1 was released, for which there are no fixes in the mainline I know
> of. If any of them have been fixed already, please let me know.
>
> If you know of any other unresolved regressions from 2.6.24, please let me know
> either and I'll add them to the list. Also, please let me know if any of the
> entries below are invalid.
>
>
> Listed regressions statistics:
>
> Date Total Pending Unresolved
> ----------------------------------------
> 2008-03-10 138 66 47
> 2008-03-03 115 65 49
> 2008-02-25 90 51 39
> 2008-02-17 61 45 37
>
>
> Unresolved regressions
> ----------------------
> Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=9978
> Subject : 2.6.25-rc1: volanoMark 45% regression
> Submitter : Zhang, Yanmin <yanmin_zhang@linux.intel.com>
> Date : 2008-02-13 10:30
> References : http://lkml.org/lkml/2008/2/13/128
> Handled-By : Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
> Balbir Singh <balbir@linux.vnet.ibm.com>
Peter reverted the load balance patch and 2.6.25-rc4 accepted the reverting patch.

With kernel 2.6.25-rc5, volanoMark has about 6% regression on my 16-core tigerton. If I apply
patch http://lkml.org/lkml/2008/2/20/83 which fixes the tbench regression issue, volanoMark
regression becomes about 4%.

I tried to bisect down which patch caused the last 4%, but found it's very hard. One thing
is many patches depend on the reverted patches. The other thing is I find the testing result
isn't stable since 2.6.25-rc1. The result variation might be more than 15% sometimes. I ran the
testing against the same kernel for many times to get the best result.

I also tried to tune some sched_XXX parameters under /proc/sys/kernel, but didn't get better result
than the default configuration.

Above regression exists on the 2.93GHz 16-core tigerton. With the less powerful 2.40GHz 16-core
tigerton, the regression is less than 1%, but result is not stable and results of many runs might have
about 15% variation.

On 8-core stoakley, the regression is about 1%.

Sorry for the late update.

-yanmin




\
 
 \ /
  Last update: 2008-03-12 09:53    [from the cache]
©2003-2014 Jasper Spaans. Advertise on this site