Re: [PATCH] sched: Initialize rq->age_stamp on processor start

2014-05-09 Thread Peter Zijlstra
On Thu, May 08, 2014 at 01:47:39PM -0500, miny...@acm.org wrote: > From: Corey Minyard > > If the sched_clock time starts at a large value, the kernel will spin > in sched_avg_update for a long time while rq->age_stamp catches up > with rq->clock. > > The comment in kernel/sched/clock.c says tha

[PATCH] sched: Initialize rq->age_stamp on processor start

2014-05-08 Thread minyard
From: Corey Minyard If the sched_clock time starts at a large value, the kernel will spin in sched_avg_update for a long time while rq->age_stamp catches up with rq->clock. The comment in kernel/sched/clock.c says that there is no strict promise that it starts at zero. So initialize rq->age_sta

Re: [PATCH] sched: Initialize rq->age_stamp on processor start

2014-05-08 Thread Corey Minyard
On 05/08/2014 11:13 AM, Peter Zijlstra wrote: > On Tue, May 06, 2014 at 02:50:57PM -0500, miny...@acm.org wrote: >> From: Corey Minyard >> >> If the sched_clock time starts at a large value, the kernel will spin >> in sched_avg_update for a long time while rq->age_stamp catches up >> with rq->cloc

Re: [PATCH] sched: Initialize rq->age_stamp on processor start

2014-05-08 Thread Peter Zijlstra
On Tue, May 06, 2014 at 02:50:57PM -0500, miny...@acm.org wrote: > From: Corey Minyard > > If the sched_clock time starts at a large value, the kernel will spin > in sched_avg_update for a long time while rq->age_stamp catches up > with rq->clock. > > The comment in kernel/sched/clock.c says tha

[PATCH] sched: Initialize rq->age_stamp on processor start

2014-05-06 Thread minyard
From: Corey Minyard If the sched_clock time starts at a large value, the kernel will spin in sched_avg_update for a long time while rq->age_stamp catches up with rq->clock. The comment in kernel/sched/clock.c says that there is no strict promise that it starts at zero. So initialize rq->age_sta

Re: [PATCH] sched: Initialize rq->age_stamp on processor start

2014-03-18 Thread Mike Galbraith
On Tue, 2014-03-18 at 09:56 +0100, Peter Zijlstra wrote: > On Tue, Mar 18, 2014 at 05:06:26AM +0100, Mike Galbraith wrote: > > > +static void __cpuinit set_cpu_rq_start_time(void) > > > +{ > > > + int cpu = smp_processor_id(); > > > + struct rq *rq = cpu_rq(cpu); > > > + rq->age_stamp = sched_clo

Re: [PATCH] sched: Initialize rq->age_stamp on processor start

2014-03-18 Thread Peter Zijlstra
On Tue, Mar 18, 2014 at 05:06:26AM +0100, Mike Galbraith wrote: > CC maintainer improves patch aerodynamics. hehe, for sure. I have very little time to look at lkml these days and there's a near 100% chance I'll miss anything that doesn't hit the inbox. > On Mon, 2014-03-17 at 19:05 -0500, miny..

Re: [PATCH] sched: Initialize rq->age_stamp on processor start

2014-03-17 Thread Mike Galbraith
CC maintainer improves patch aerodynamics. On Mon, 2014-03-17 at 19:05 -0500, miny...@acm.org wrote: > From: Corey Minyard > > If the sched_clock time starts at a large value, the kernel will spin > in sched_avg_update for a long time while rq->age_stamp catches up > with rq->clock. > > The co

[PATCH] sched: Initialize rq->age_stamp on processor start

2014-03-17 Thread minyard
From: Corey Minyard If the sched_clock time starts at a large value, the kernel will spin in sched_avg_update for a long time while rq->age_stamp catches up with rq->clock. The comment in kernel/sched/clock.c says that there is no strict promise that it starts at zero. So initialize rq->age_sta