On 17/04/19 15:23, Christian Borntraeger wrote: > > > On 17.04.19 15:20, Paolo Bonzini wrote: >> On 16/04/19 20:01, Christian Borntraeger wrote: >>> v1->v2: >>> - add kvm_vcpu parameter to kvm_arch_no_poll >>> - add kvm stat in the s390 implementation >>> - make the value tunable >>> >>> Folks, >>> >>> this is a very simple variant to disable halt polling when the KVM host >>> is already running virtualized. We could imagine more complex variants >>> (like tuning down the halt polling value) but this seems to do the trick >>> for some kvm deployment scenarios on s390x. (e.g. having multiple LPARS >>> with KVMs that are in itself already overcommitted). >> >> Ok to queue this for 5.2? > > Yes, after review. I can queue that in the s390 tree if you want. Sure, that's okay. Paolo >> (Stupid question, I thought LPARs are partitions and as such were never >> overcommitted. What is it that separates an LPAR from a zVM or KVM guest?) > > LPAR can do CPU overcommitment as well (or dedicated whatever you configure). Its the > memory that is hard partitioned on LPAR. >
