Re: [PATCH 08/16] sched: Reschedule task on preferred NUMA node once selected

2013-07-12 Thread Mel Gorman
On Fri, Jul 12, 2013 at 12:14:08PM +0200, Peter Zijlstra wrote: > On Thu, Jul 11, 2013 at 03:09:14PM +0100, Mel Gorman wrote: > > That might be necessary when the machine is overloaded. As a > > starting point the following should retry the migrate a number of times > > until success. The retry is

Re: [PATCH 08/16] sched: Reschedule task on preferred NUMA node once selected

2013-07-12 Thread Peter Zijlstra
On Thu, Jul 11, 2013 at 03:09:14PM +0100, Mel Gorman wrote: > That might be necessary when the machine is overloaded. As a > starting point the following should retry the migrate a number of times > until success. The retry is checked on every fault but should not fire > more than once every 100ms.

Re: [PATCH 08/16] sched: Reschedule task on preferred NUMA node once selected

2013-07-11 Thread Mel Gorman
On Thu, Jul 11, 2013 at 03:11:58PM +0200, Peter Zijlstra wrote: > On Thu, Jul 11, 2013 at 02:03:22PM +0100, Mel Gorman wrote: > > On Thu, Jul 11, 2013 at 02:30:38PM +0200, Peter Zijlstra wrote: > > > On Thu, Jul 11, 2013 at 10:46:52AM +0100, Mel Gorman wrote: > > > > @@ -829,10 +854,29 @@ static vo

Re: [PATCH 08/16] sched: Reschedule task on preferred NUMA node once selected

2013-07-11 Thread Peter Zijlstra
On Thu, Jul 11, 2013 at 02:03:22PM +0100, Mel Gorman wrote: > On Thu, Jul 11, 2013 at 02:30:38PM +0200, Peter Zijlstra wrote: > > On Thu, Jul 11, 2013 at 10:46:52AM +0100, Mel Gorman wrote: > > > @@ -829,10 +854,29 @@ static void task_numa_placement(struct task_struct > > > *p) > > > } >

Re: [PATCH 08/16] sched: Reschedule task on preferred NUMA node once selected

2013-07-11 Thread Mel Gorman
On Thu, Jul 11, 2013 at 02:30:38PM +0200, Peter Zijlstra wrote: > On Thu, Jul 11, 2013 at 10:46:52AM +0100, Mel Gorman wrote: > > @@ -829,10 +854,29 @@ static void task_numa_placement(struct task_struct *p) > > } > > } > > > > - /* Update the tasks preferred node if necessary */

Re: [PATCH 08/16] sched: Reschedule task on preferred NUMA node once selected

2013-07-11 Thread Peter Zijlstra
On Thu, Jul 11, 2013 at 10:46:52AM +0100, Mel Gorman wrote: > @@ -829,10 +854,29 @@ static void task_numa_placement(struct task_struct *p) > } > } > > - /* Update the tasks preferred node if necessary */ > + /* > + * Record the preferred node as the node with the

[PATCH 08/16] sched: Reschedule task on preferred NUMA node once selected

2013-07-11 Thread Mel Gorman
A preferred node is selected based on the node the most NUMA hinting faults was incurred on. There is no guarantee that the task is running on that node at the time so this patch rescheules the task to run on the most idle CPU of the selected node when selected. This avoids waiting for the balancer