Author: mav
Date: Fri Mar 9 19:09:08 2012
New Revision: 232740
URL: http://svn.freebsd.org/changeset/base/232740
Log:
Make kern.sched.idlespinthresh default value adaptive depending of HZ.
Otherwise with HZ above 8000 CPU may never skip timer ticks on idle.
Modified:
head/sys/kern/sched_ule.c
Modified: head/sys/kern/sched_ule.c
==============================================================================
--- head/sys/kern/sched_ule.c Fri Mar 9 18:50:49 2012 (r232739)
+++ head/sys/kern/sched_ule.c Fri Mar 9 19:09:08 2012 (r232740)
@@ -212,7 +212,7 @@ static int preempt_thresh = 0;
#endif
static int static_boost = PRI_MIN_BATCH;
static int sched_idlespins = 10000;
-static int sched_idlespinthresh = 16;
+static int sched_idlespinthresh = -1;
/*
* tdq - per processor runqs and statistics. All fields are protected by the
@@ -1390,6 +1390,8 @@ sched_initticks(void *dummy)
steal_thresh = min(fls(mp_ncpus) - 1, 3);
affinity = SCHED_AFFINITY_DEFAULT;
#endif
+ if (sched_idlespinthresh < 0)
+ sched_idlespinthresh = max(16, 2 * hz / realstathz);
}
_______________________________________________
svn-src-head@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/svn-src-head
To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
