Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-19 02:21:47 +00:00
Code Issues Packages Projects Releases Wiki Activity

sched/numa: Add SD_PERFER_SIBLING to CPU domain

Browse Source 
Commit 8e7fbcbc22 ("sched: Remove stale power aware scheduling remnants
and dysfunctional knobs") removed SD_PERFER_SIBLING from the CPU domain.

On NUMA machines this causes that load_balance() doesn't perfer LCPU in
 same physical CPU package.

It causes some actual performance regressions on our NUMA machines from
Core2 to NHM and SNB.

Adding this domain flag again recovers the performance drop.

This change doesn't have any bad impact on any of my benchmarks:
 specjbb, kbuild, fio, hackbench .. etc, on all my machines.

Signed-off-by: Alex Shi <alex.shi@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1342765190-21540-1-git-send-email-alex.shi@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Alex Shi 2012-07-20 14:19:50 +08:00 committed by Ingo Molnar
parent 8323f26ce3
commit 6956dc568f
1 changed files with 1 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
include/linux/topology.h
View File

@ -164,6 +164,7 @@ int arch_update_cpu_topology(void);
| 0*SD_SHARE_CPUPOWER \
| 0*SD_SHARE_PKG_RESOURCES \
| 0*SD_SERIALIZE \
| 1*SD_PREFER_SIBLING \
, \
.last_balance = jiffies, \
.balance_interval = 1, \