Re: [Qemu-devel] [RFC] Next gen kvm api

[Avi Kivity]

On 02/06/2012 09:11 PM, Anthony Liguori wrote:
> I'm not so sure.  ioeventfds and a future mmio-over-socketpair have to 
> put the kthread to sleep while it waits for the other end to process 
> it.  This is effectively equivalent to a heavy weight exit.  The 
> difference in cost is dropping to userspace which is really neglible 
> these days (< 100 cycles).

On what machine did you measure these wonderful numbers?

But I agree a heavyweight exit is probably faster than a double context 
switch on a remote core.


--
I have a truly marvellous patch that fixes the bug which this
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