Re: [RFC PATCH] kernel/sched/core: busy wait before going idle

2018-04-23 Thread Nicholas Piggin
On Mon, 23 Apr 2018 15:47:40 +0530 Pavan Kondeti wrote: > Hi Nick, > > On Sun, Apr 15, 2018 at 11:31:49PM +1000, Nicholas Piggin wrote: > > This is a quick hack for comments, but I've always wondered -- > > if we have a short term polling idle states in cpuidle for performance > > -- why not ski

Re: [RFC PATCH] kernel/sched/core: busy wait before going idle

2018-04-23 Thread Pavan Kondeti
Hi Nick, On Sun, Apr 15, 2018 at 11:31:49PM +1000, Nicholas Piggin wrote: > This is a quick hack for comments, but I've always wondered -- > if we have a short term polling idle states in cpuidle for performance > -- why not skip the context switch and entry into all the idle states, > and just wa

Re: [RFC PATCH] kernel/sched/core: busy wait before going idle

2018-04-20 Thread Nicholas Piggin
On Fri, 20 Apr 2018 12:58:27 +0200 Peter Zijlstra wrote: > On Fri, Apr 20, 2018 at 07:01:47PM +1000, Nicholas Piggin wrote: > > On Fri, 20 Apr 2018 09:44:56 +0200 > > Peter Zijlstra wrote: > > > > > On Sun, Apr 15, 2018 at 11:31:49PM +1000, Nicholas Piggin wrote: > > > > This is a quick hac

Re: [RFC PATCH] kernel/sched/core: busy wait before going idle

2018-04-20 Thread Peter Zijlstra
On Fri, Apr 20, 2018 at 07:01:47PM +1000, Nicholas Piggin wrote: > On Fri, 20 Apr 2018 09:44:56 +0200 > Peter Zijlstra wrote: > > > On Sun, Apr 15, 2018 at 11:31:49PM +1000, Nicholas Piggin wrote: > > > This is a quick hack for comments, but I've always wondered -- > > > if we have a short term p

Re: [RFC PATCH] kernel/sched/core: busy wait before going idle

2018-04-20 Thread Nicholas Piggin
On Fri, 20 Apr 2018 09:44:56 +0200 Peter Zijlstra wrote: > On Sun, Apr 15, 2018 at 11:31:49PM +1000, Nicholas Piggin wrote: > > This is a quick hack for comments, but I've always wondered -- > > if we have a short term polling idle states in cpuidle for performance > > -- why not skip the context

Re: [RFC PATCH] kernel/sched/core: busy wait before going idle

2018-04-20 Thread Peter Zijlstra
On Sun, Apr 15, 2018 at 11:31:49PM +1000, Nicholas Piggin wrote: > This is a quick hack for comments, but I've always wondered -- > if we have a short term polling idle states in cpuidle for performance > -- why not skip the context switch and entry into all the idle states, > and just wait for a b

[RFC PATCH] kernel/sched/core: busy wait before going idle

2018-04-15 Thread Nicholas Piggin
This is a quick hack for comments, but I've always wondered -- if we have a short term polling idle states in cpuidle for performance -- why not skip the context switch and entry into all the idle states, and just wait for a bit to see if something wakes up again. It's not uncommon to see various