Re: Fwd: Kernel Power management ?? turning off used devices that are in use.

Matthew Garrett
2011-11-07T17:05:10Z

On Fri, Nov 04, 2011 at 02:56:25PM +0800, hagar wrote:
>
> I have traced this behaviour to the cpu hotplug code.
>
> I need to be able to either switch off cpu hotpluging - or at least
> prevent hotplugging certain cpu's

The kernel doesn't automatically hotplug CPUs on idle. Something in your
userspace is doing so. I think that Ubuntu's powernap will do so under
certain circumstances - try disabling that if you have it.

(Which doesn't alter the fact that there appears to be a bug here)

--
Matthew Garrett | mjg59@srcf.ucam.org