On Thu, 1 Aug 2019 at 20:57, Dario Faggioli <dfaggioli@xxxxxxxx> wrote: > > On Tue, 2019-07-30 at 17:33 +0800, Wanpeng Li wrote: > > However, in multiple VMs over-subscribe virtualization scenario, it > > increases > > the probability to incur vCPU stacking which means that the sibling > > vCPUs from > > the same VM will be stacked on one pCPU. I test three 80 vCPUs VMs > > running on > > one 80 pCPUs Skylake server(PLE is supported), the ebizzy score can > > increase 17% > > after disabling wake-affine for vCPU process. > > > Can't we achieve this by removing SD_WAKE_AFFINE from the relevant > scheduling domains? By acting on > /proc/sys/kernel/sched_domain/cpuX/domainY/flags, I mean? > > Of course this will impact all tasks, not only KVM vcpus. But if the > host does KVM only anyway... Yes, not only kvm host and dedicated kvm host, unless introduce per-process flags, otherwise can't appeal to both. Regards, Wanpeng Li
