Re: [PATCH 3/4] sched: Comment on why sync wakeups try to run on the current CPU

2017-12-19 Thread Mike Galbraith
On Wed, 2017-12-20 at 05:09 +0100, Mike Galbraith wrote: >  Nope, stacking based upon that > hint is most definitely not a good idea :) Except when heavily loaded. The only thing worse for communicating hogs being stacked is communicating hogs talking with another hog between them.

Re: [PATCH 3/4] sched: Comment on why sync wakeups try to run on the current CPU

2017-12-19 Thread Mike Galbraith
On Tue, 2017-12-19 at 20:06 +0100, Peter Zijlstra wrote: > > Our SYNC hint does promise the caller will go away 'soon', although I'm > not sure how many of the current users actually honor that. The sync hint is not a lie, or even a damn lie, it's a statistic :) It's very useful for...

Re: [PATCH 3/4] sched: Comment on why sync wakeups try to run on the current CPU

2017-12-19 Thread Mel Gorman
On Tue, Dec 19, 2017 at 08:06:44PM +0100, Peter Zijlstra wrote: > On Mon, Dec 18, 2017 at 09:43:26AM +, Mel Gorman wrote: > > The sync wakeup logic in wake_affine_idle deserves a short description. > > > > Signed-off-by: Mel Gorman > > --- > >

Re: [PATCH 3/4] sched: Comment on why sync wakeups try to run on the current CPU

2017-12-19 Thread Peter Zijlstra
On Mon, Dec 18, 2017 at 09:43:26AM +, Mel Gorman wrote: > The sync wakeup logic in wake_affine_idle deserves a short description. > > Signed-off-by: Mel Gorman > --- > kernel/sched/fair.c | 5 + > 1 file changed, 5 insertions(+) > > diff --git

[PATCH 3/4] sched: Comment on why sync wakeups try to run on the current CPU

2017-12-18 Thread Mel Gorman
The sync wakeup logic in wake_affine_idle deserves a short description. Signed-off-by: Mel Gorman --- kernel/sched/fair.c | 5 + 1 file changed, 5 insertions(+) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 392e08b364bd..95b1145bc38d 100644 ---