Re: [PATCH RFC 1/2] sched: Minimize the idle cpu selection race window.

From: Atish Patra
Date: Wed Nov 01 2017 - 12:37:13 EST




On 11/01/2017 02:18 AM, Mike Galbraith wrote:
On Wed, 2017-11-01 at 07:54 +0100, Mike Galbraith wrote:
On Wed, 2017-11-01 at 01:08 -0500, Atish Patra wrote:

Do you have the schbench configuration somewhere that I can test? I
tried various configurations but did not
see any improvement or regression.
No, as noted, I didn't save anything. I watched and fiddled with
several configurations on various sized boxen, doing this/that on top
of the reservation thing to try to improve the "it's 100% about perfect
spread" schbench, but didn't like the pricetag, so tossed the lot over
my shoulder and walked away.
:)
BTW, the biggest trouble with schbench at that time was not so much
about wakeup time stacking (though it was visible), it was using load
averages instead of instantaneous state, and sawtoothing therein.
Ahh I see. Any other benchmark suggestion that may benefit from this fix ?

Regards,
Atish
-Mike