> On 11/28/2014 04:28 PM, Christian Borntraeger wrote: > > Am 28.11.2014 um 11:08 schrieb Raghavendra KT: > >> Was able to test the patch, here is the result: I have not tested with > >> bigger VMs though. Results make it difficult to talk about any side > >> effect of > >> patch if any. > > > > Thanks a log. > > > > If our assumption is correct, then this patch should have no side effect on x86. Do you have any confidence guess if the numbers below mean: no-change vs. regression vs improvement? > > > > I am seeing very small improvement in <= 1x commit cases > and for >1x overcommit, a very slight regression. But considering the > test environment noises, I do not see much effect from the > patch. > > But I admit, I have not explored deeply about, > 1. assumption of preempted approximately equals PF_VCPU case logic, PF_VCPU is only a hint whether the target vcpu is executing the guest. If preemption is off or !s390, PF_VCPU means that the target vcpu is running and can't be preempted. Although for preemption on and s390, this statement is false. Therefore this check is not always right. > 2. whether it helps for any future usages of yield_to against current > sole usage of virtualization. > > > Thanks for your test! -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
