* Marcelo Tosatti <mtosatti@xxxxxxxxxx> [2012-01-17 13:53:03]: > on tue, jan 17, 2012 at 05:32:33pm +0200, gleb natapov wrote: > > on tue, jan 17, 2012 at 07:58:18pm +0530, srivatsa vaddagiri wrote: > > > * gleb natapov <gleb@xxxxxxxxxx> [2012-01-17 15:20:51]: > > > > > > > > having the hypercall makes the intent of vcpu (to sleep on a kick) clear to > > > > > hypervisor vs assuming that because of a trapped hlt instruction (which > > > > > will anyway won't work when yield_on_hlt=0). > > > > > > > > > the purpose of yield_on_hlt=0 is to allow vcpu to occupy cpu for the > > > > entire time slice no mater what. i do not think disabling yield on hlt > > > > is even make sense in cpu oversubscribe scenario. > > > > > > Yes, so is there any real use for yield_on_hlt=0? I believe Anthony > > > initially added it as a way to implement CPU bandwidth capping for VMs, > > > which would ensure that busy VMs don't eat into cycles meant for a idle > > > VM. Now that we have proper support in scheduler for CPU bandwidth capping, is > > > there any real world use for yield_on_hlt=0? If not, deprecate it? > > > > > I was against adding it in the first place, so if IBM no longer needs it > > I am for removing it ASAP. > > +1. > > Anthony? CCing Anthony. Anthony, could you ACK removal of yield_on_hlt (as keeping it around will require unnecessary complications in pv-spinlock patches)? - vatsa _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
