Date: Mon, 4 Jun 2012 07:12:36 +0000 (UTC) From: Alexander Motin <mav@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-9@freebsd.org Subject: svn commit: r236546 - stable/9/sys/kern Message-ID: <201206040712.q547CaOt011828@svn.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: mav Date: Mon Jun 4 07:12:36 2012 New Revision: 236546 URL: http://svn.freebsd.org/changeset/base/236546 Log: MFC r232740: Make kern.sched.idlespinthresh default value adaptive depending of HZ. Otherwise with HZ above 8000 CPU may never skip timer ticks on idle. Modified: stable/9/sys/kern/sched_ule.c Directory Properties: stable/9/sys/ (props changed) Modified: stable/9/sys/kern/sched_ule.c ============================================================================== --- stable/9/sys/kern/sched_ule.c Mon Jun 4 07:12:11 2012 (r236545) +++ stable/9/sys/kern/sched_ule.c Mon Jun 4 07:12:36 2012 (r236546) @@ -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 @@ -1410,6 +1410,8 @@ 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); }
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201206040712.q547CaOt011828>