Re: NUMA aware slab allocator V3

Jesse Barnes
2005-05-19T16:14:19Z

On Wednesday, May 18, 2005 10:07 pm, Christoph Lameter wrote:
> Here is a revised patch. Would be good if someone could review my use
> of online_cpu / online_node etc. Is there some way to bring cpus
> online and offline to test if this really works? Seems that the code
> in alloc_percpu is suspect even in the old allocator because it may
> have to allocate memory for non present cpus.

If you have hotplug enabled, I think you'll see an 'online' file that
you can echo 1 or 0 into, somewhere in /sys/devices/system/cpu/cpu0 for
example. It should work even on machines where it doesn't actually
power down the slot (it'll just remove it from the online map, and it
won't get scheduled on, etc.); at least it did last time I tested it.

Jesse