Re: [RFC PATCH 12/12] housekeeping: Reimplement isolcpus on housekeeping

From: Christopher Lameter
Date: Wed Aug 23 2017 - 10:55:59 EST


On Wed, 23 Aug 2017, Frederic Weisbecker wrote:

> While at it, this is a proposition for a reimplementation of isolcpus=
> that doesn't involve scheduler domain isolation. Therefore this
> brings a behaviour change: all user tasks inherit init/1 affinity which
> avoid the isolcpus= range. But if a task later overrides its affinity
> which turns out to intersect an isolated CPU, load balancing may occur
> on it.

I think that change is good maybe even a bugfix. I had some people be very
surprised when they set affinities to multiple cpus and the processeds
kept sticking to one cpu because of isolcpus.