Re: sched: tweak select_idle_sibling to look for idle threads

From: Peter Zijlstra
Date: Thu May 05 2016 - 05:33:45 EST

On Wed, May 04, 2016 at 01:46:16PM -0400, Chris Mason wrote:
> It should, make sure you're at the top commit in git.
> git://

I did double check; I am on the top commit of that. I refetched and
rebuild just to make tripple sure.

> It's not recent so I'd be surprised if you weren't already there. The
> default runtime is 30 seconds, but you can use -r to specify something
> shorter.
> It's possible I'm missing a wakeup to shut the whole thing down, but I
> thought I fixed that.

Seems to still be missing, because:

> ./schbench -p 4 -m 1 -t 1
> Latency percentiles (usec)
> 50.0000th: 5
> 75.0000th: 5
> 90.0000th: 5
> 95.0000th: 5
> *99.0000th: 8
> 99.5000th: 15
> 99.9000th: 17
> Over=0, min=0, max=652
> avg worker transfer: 113768.27 ops/sec 444.41KB/s

is not what mine does. I get ~25sec of cpu time and then it stalls

I'll try and have a prod at the program itself if you have no pending
changes on your end.