Subject : tbench regression with 2.6.32-rc1
Submitter : "Zhang, Yanmin" <firstname.lastname@example.org>
Date : 2009-10-09 9:51
References : http://marc.info/?l=linux-kernel&m=125508216713138&w=4
Handled-By : Peter Zijlstra <email@example.com>
This entry is being used for tracking a regression from 2.6.31. Please don't
close it until the problem is fixed in the mainline.
Author: Peter Zijlstra <firstname.lastname@example.org>
Date: Wed Sep 16 08:28:30 2009 +0200
sched: Add SD_PREFER_LOCAL
First-Bad-Commit : 59abf02644c45f1591e1374ee7bb45dc757fcb88
With kernel 2.6.32-rc7:
On core2 arch machines, tbench regression becomes about 4%. Originally, the
regression is about 33%.
On Nehalem, tbench regression is about 4%. Original is 7%.
On Itanium, tbench regression is about 16%. Original is 26%
As for the surplus regression, I suspect it's related to commit de69a80be32445. Peter already has an improved patch against commit de69a80be32445.
As the regression becomes far smaller, we might close the bug report now.