Re: [PATCH] kvm tools: Add MMIO coalescing support

Ingo Molnar
2011-06-04T09:39:03Z

* Sasha Levin <levinsasha928@gmail.com> wrote:

> Coalescing MMIO allows us to avoid an exit every time we have a
> MMIO write, instead - MMIO writes are coalesced in a ring which
> can be flushed once an exit for a different reason is needed.
> A MMIO exit is also trigged once the ring is full.
>
> Coalesce all MMIO regions registered in the MMIO mapper.
> Add a coalescing handler under kvm_cpu.

Does this have any effect on latency? I.e. does the guest side
guarantee that the pending queue will be flushed after a group of
updates have been done?

Thanks,

Ingo