Re: [PATCH] kvm: add halt_poll_ns module parameter

From: Paolo Bonzini
Date: Tue Feb 10 2015 - 02:51:19 EST

On 09/02/2015 22:00, Christian Borntraeger wrote:
> I can confirm that this also helps uperf with a 1/1 byte round trip work load
> between guests on s390. And I can confirm the higher CPU load. This is normally
> a no-go for the typical s390 users, which utilize their systems as much as
> possible. Your check for single_task_running could actually solve that
> problem because on overcommitment this will never switch to polling if the
> runqueues get full.
> Since this is also runtime configurable and defaults to 0 it should be pretty
> painless.
> The only question is: is there a sane way of doing autotuning?

The answer is: we'll see. :) I have some ideas, I have to run them
through the necessary experiments.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at