lkml.org 
[lkml]   [2006]   [Nov]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: 2.6.19-rc5: known regressions
From
Date
On Wed, 2006-11-08 at 17:22 +0100, Adrian Bunk wrote:

> There's perhaps one thing that might help us to see whether it's just a
> benchmark effekt or a real problem:
>
> With Tim's CONFIG_NR_CPUS=8, NR_IRQS only increases from 224 in 2.6.18
> to 512 in 2.6.19-rc.
>
> With CONFIG_NR_CPUS=255, NR_IRQS increases from 224 in 2.6.18
> to 8416 in 2.6.19-rc.
>
> @Tim:
> Can you try CONFIG_NR_CPUS=255 with both 2.6.18 and 2.6.19-rc5?
>

With CONFIG_NR_CPUS increased from 8 to 64:
2.6.18 see no change in fork time measured.
2.6.19-rc5 see a 138% increase in fork time.

When I increase CONFIG_NR_CPUS to 128, the child process
from fork got killed when it executes sched_getaffinity call
in the routine to pin the process onto a processor.
This happened for both 2.6.18 and 2.6.19-rc5.
I'll need to check more carefully what lmbench is doing
there.

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

\
 
 \ /
  Last update: 2006-11-09 01:03    [W:0.311 / U:0.164 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site