From 59abf02644c45f1591e1374ee7bb45dc757fcb88 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 16 Sep 2009 08:28:30 +0200 Subject: sched: Add SD_PREFER_LOCAL And turn it on for NUMA and MC domains. This improves locality in balancing decisions by keeping up to capacity amount of tasks local before looking for idle CPUs. (and twice the capacity if SD_POWERSAVINGS_BALANCE is set.) Signed-off-by: Peter Zijlstra LKML-Reference: Signed-off-by: Ingo Molnar --- kernel/sched_fair.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index 280892e..a37f311 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -1360,7 +1360,7 @@ static int select_task_rq_fair(struct task_struct *p, int sd_flag, int flags) * If power savings logic is enabled for a domain, see if we * are not overloaded, if so, don't balance wider. */ - if (tmp->flags & SD_POWERSAVINGS_BALANCE) { + if (tmp->flags & (SD_POWERSAVINGS_BALANCE|SD_PREFER_LOCAL)) { unsigned long power = 0; unsigned long nr_running = 0; unsigned long capacity; @@ -1373,7 +1373,10 @@ static int select_task_rq_fair(struct task_struct *p, int sd_flag, int flags) capacity = DIV_ROUND_CLOSEST(power, SCHED_LOAD_SCALE); - if (nr_running/2 < capacity) + if (tmp->flags & SD_POWERSAVINGS_BALANCE) + nr_running /= 2; + + if (nr_running < capacity) break; } -- cgit v1.1