Il 23/05/2013 15:30, Peter Lieven ha scritto: >>>> So I would prefer to remove kvm->arch.hv_ref_count altogether. >>> >>> But only if the migration support is guaranteed. >> >> Migration support wouldn't work yet anyway, you need to recompute the >> scale and sequence. But that could be done by KVM_SET_CLOCK. > > hv_ref_counter does work out of the box. what I was trying to say is > even it is slower than iTSC, it is significantly faster than hpet > or pmtimer and I can confirm it works flawlessly with migration. I can't see how without a userspace patch to migrate hv_ref_count. >>> And what if we have a host which lacks invariant TSC support? >> >> Then the sequence must be set to 0 or 0xFFFFFFFF, I still haven't >> understood. :) > > yes, but windows does then fall back to pmtimer or hpet which is much > slower then reference counter. IIUC, with 0 it doesn't. Paolo -- 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
