Re: [PATCH 3/3] sched: Spare idle load balancing on nohz_full CPUs

2017-06-21 Thread Frederic Weisbecker
On Tue, Jun 20, 2017 at 09:06:48PM +0200, Mike Galbraith wrote: > On Tue, 2017-06-20 at 13:42 -0400, Rik van Riel wrote: > > On Mon, 2017-06-19 at 04:12 +0200, Frederic Weisbecker wrote: > > > Although idle load balancing obviously only concern idle CPUs, it can > > > be a disturbance on a busy

Re: [PATCH 3/3] sched: Spare idle load balancing on nohz_full CPUs

2017-06-21 Thread Frederic Weisbecker
On Tue, Jun 20, 2017 at 09:06:48PM +0200, Mike Galbraith wrote: > On Tue, 2017-06-20 at 13:42 -0400, Rik van Riel wrote: > > On Mon, 2017-06-19 at 04:12 +0200, Frederic Weisbecker wrote: > > > Although idle load balancing obviously only concern idle CPUs, it can > > > be a disturbance on a busy

Re: [PATCH 3/3] sched: Spare idle load balancing on nohz_full CPUs

2017-06-20 Thread Frederic Weisbecker
On Tue, Jun 20, 2017 at 01:42:27PM -0400, Rik van Riel wrote: > On Mon, 2017-06-19 at 04:12 +0200, Frederic Weisbecker wrote: > > Although idle load balancing obviously only concern idle CPUs, it can > > be a disturbance on a busy nohz_full CPU. Indeed a CPU can only get > > rid > > of an idle

Re: [PATCH 3/3] sched: Spare idle load balancing on nohz_full CPUs

2017-06-20 Thread Frederic Weisbecker
On Tue, Jun 20, 2017 at 01:42:27PM -0400, Rik van Riel wrote: > On Mon, 2017-06-19 at 04:12 +0200, Frederic Weisbecker wrote: > > Although idle load balancing obviously only concern idle CPUs, it can > > be a disturbance on a busy nohz_full CPU. Indeed a CPU can only get > > rid > > of an idle

Re: [PATCH 3/3] sched: Spare idle load balancing on nohz_full CPUs

2017-06-20 Thread Mike Galbraith
On Tue, 2017-06-20 at 13:42 -0400, Rik van Riel wrote: > On Mon, 2017-06-19 at 04:12 +0200, Frederic Weisbecker wrote: > > Although idle load balancing obviously only concern idle CPUs, it can > > be a disturbance on a busy nohz_full CPU. Indeed a CPU can only get > > rid > > of an idle load

Re: [PATCH 3/3] sched: Spare idle load balancing on nohz_full CPUs

2017-06-20 Thread Mike Galbraith
On Tue, 2017-06-20 at 13:42 -0400, Rik van Riel wrote: > On Mon, 2017-06-19 at 04:12 +0200, Frederic Weisbecker wrote: > > Although idle load balancing obviously only concern idle CPUs, it can > > be a disturbance on a busy nohz_full CPU. Indeed a CPU can only get > > rid > > of an idle load

Re: [PATCH 3/3] sched: Spare idle load balancing on nohz_full CPUs

2017-06-20 Thread Rik van Riel
On Mon, 2017-06-19 at 04:12 +0200, Frederic Weisbecker wrote: > Although idle load balancing obviously only concern idle CPUs, it can > be a disturbance on a busy nohz_full CPU. Indeed a CPU can only get > rid > of an idle load balancing duty once a tick fires while it runs a task > and this can

Re: [PATCH 3/3] sched: Spare idle load balancing on nohz_full CPUs

2017-06-20 Thread Rik van Riel
On Mon, 2017-06-19 at 04:12 +0200, Frederic Weisbecker wrote: > Although idle load balancing obviously only concern idle CPUs, it can > be a disturbance on a busy nohz_full CPU. Indeed a CPU can only get > rid > of an idle load balancing duty once a tick fires while it runs a task > and this can

[PATCH 3/3] sched: Spare idle load balancing on nohz_full CPUs

2017-06-18 Thread Frederic Weisbecker
Although idle load balancing obviously only concern idle CPUs, it can be a disturbance on a busy nohz_full CPU. Indeed a CPU can only get rid of an idle load balancing duty once a tick fires while it runs a task and this can take a while in a nohz_full CPU. We could fix that and escape the idle

[PATCH 3/3] sched: Spare idle load balancing on nohz_full CPUs

2017-06-18 Thread Frederic Weisbecker
Although idle load balancing obviously only concern idle CPUs, it can be a disturbance on a busy nohz_full CPU. Indeed a CPU can only get rid of an idle load balancing duty once a tick fires while it runs a task and this can take a while in a nohz_full CPU. We could fix that and escape the idle