Subject: Re: Topology updates and NUMA-level sched domains

From: Nishanth Aravamudan <[email-masked]>
Date: Thu, 9 Apr 2015 15:37:09 -0700

On 08.04.2015 [12:32:01 +0200], Brice Goglin wrote:
> Le 07/04/2015 21:41, Peter Zijlstra a écrit :
> > No, that's very much not the same. Even if it were dealing with hotplug
> > it would still assume the cpu to return to the same node.
> >
> > But mostly people do not even bother to handle hotplug.
> >
> 
> You said userspace assumes the cpu<->node relation is a boot-time fixed
> one, and hotplug breaks this. How do you expect userspace to handle
> hotplug? Is there a convenient way to be notified when a CPU (or memory)
> is unplugged?

There is some mention of "User Space Notification" in cpu-hotplug.txt,
but no idea if it's current.

-Nish