Re: [PATCH v5 08/12] Inject asynchronous page fault into a guest if page is swapped out.

Avi Kivity
2010-08-24T09:05:30Z

On 08/24/2010 10:52 AM, Gleb Natapov wrote:
>> This nice cache needs to be outside apf to reduce complexity for
>> reviewers and since it is useful for others.
>>
>> Would be good to have memslot-cached kvm_put_guest() and kvm_get_guest().
> Will look into it.

In the meantime, you can just drop the caching.

>>> + struct kvm_arch_async_pf *arch)
>>> +{
>>> + struct kvm_async_pf *work;
>>> +
>>> + if (vcpu->async_pf_queued>= ASYNC_PF_PER_VCPU)
>>> + return 0;
>> 100 == too high. At 16 vcpus, this allows 1600 kernel threads to
>> wait for I/O.
> Number of kernel threads are limited by other means. Slow work subsystem
> has its own knobs to tune that. Here we limit how much slow work items
> can be queued per vcpu.

OK.

>> Would have been best if we could ask for a page to be paged in
>> asynchronously.
>>
> You mean to have core kernel facility for that? I agree it would be
> nice, but much harder.

Yes, that's what I meant.

--
error compiling committee.c: too many arguments to function