Mike Galbraith 970e178985 sched: Improve scalability via 'CPU buddies', which withstand random perturbations ... Traversing an entire package is not only expensive, it also leads to tasks bouncing all over a partially idle and possible quite large package. Fix that up by assigning a 'buddy' CPU to try to motivate. Each buddy may try to motivate that one other CPU, if it's busy, tough, it may then try its SMT sibling, but that's all this optimization is allowed to cost. Sibling cache buddies are cross-wired to prevent bouncing. 4 socket 40 core + SMT Westmere box, single 30 sec tbench runs, higher is better: clients 1 2 4 8 16 32 64 128 .......................................................................... pre 30 41 118 645 3769 6214 12233 14312 post 299 603 1211 2418 4697 6847 11606 14557 A nice increase in performance. Signed-off-by: Mike Galbraith <efault@gmx.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1339471112.7352.32.camel@marge.simpson.net Signed-off-by: Ingo Molnar <mingo@kernel.org>		2012-07-24 13:53:34 +02:00
..
auto_group.c	sched: Clean up parameter passing of proc_sched_autogroup_set_nice()	2012-03-02 12:23:49 +01:00
auto_group.h
clock.c
core.c	sched: Improve scalability via 'CPU buddies', which withstand random perturbations	2012-07-24 13:53:34 +02:00
cpupri.c	kernel-doc: fix kernel-doc warnings in sched	2012-01-23 08:44:54 -08:00
cpupri.h
debug.c	sched/debug: Fix printing large integers on 32-bit platforms	2012-05-14 15:05:28 +02:00
fair.c	sched: Improve scalability via 'CPU buddies', which withstand random perturbations	2012-07-24 13:53:34 +02:00
features.h	sched: Fix more load-balancing fallout	2012-04-26 12:54:52 +02:00
idle_task.c	sched/nohz: Rewrite and fix load-avg computation -- again	2012-07-05 20:58:13 +02:00
Makefile	init_task: Create generic init_task instance	2012-05-05 13:00:21 +02:00
rt.c	sched/rt: Fix lockdep annotation within find_lock_lowest_rq()	2012-06-06 16:52:26 +02:00
sched.h	sched/nohz: Rewrite and fix load-avg computation -- again	2012-07-05 20:58:13 +02:00
stats.c	sched: Remove sched_switch	2012-01-27 13:28:53 +01:00
stats.h
stop_task.c