On 01/07/2011 09:03 PM, Jan Kiszka wrote:
>>
>> So, if you have a good high-bandwidth test case at hand, I would
>> appreciate if you could give this a try and report your findings. Does
>> switching from exclusive to shared IRQ mode decrease the throughput or
>> increase the host load? Is there a difference to current kvm?
>
> I think any sufficiently high bandwidth device will be using MSI and or
> NAPI, so I wouldn't expect we're going to see much change there.
That's also why I'm no longer sure it's worth to worry about irq_disable
vs. PCI disable. Anyone who cares about performance in a large
pass-through scenario will try to use MSI-capable hardware anyway (or
was so far unable to use tons of legacy IRQ driven devices due to IRQ
conflicts).
PCI disable is probably only ridiculously slow with cf8/cfc config space
access, and significantly faster (though still slow) with mmconfig.
Needs to be taken into account as well.
--
error compiling committee.c: too many arguments to function
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
