Re: [RFC PATCH v2 0/7] x86/idle: add halt poll support

From: Andi Kleen
Date: Tue Aug 29 2017 - 09:03:39 EST


Yang Zhang <yang.zhang.wz@xxxxxxxxx> writes:

> Some latency-intensive workload will see obviously performance
> drop when running inside VM. The main reason is that the overhead
> is amplified when running inside VM. The most cost i have seen is
> inside idle path.

You could test with https://lkml.org/lkml/2017/7/9/204
which optimizes these idle paths with a fast path.

If that works it would be a far better solution than
explicit tunables and basically giving up by polling.

-Andi