On 20/06/2018 16:29, Michael S. Tsirkin wrote: > On Wed, Jun 20, 2018 at 04:20:40PM +0200, Paolo Bonzini wrote: >> On 19/06/2018 22:43, Michael S. Tsirkin wrote: >>> >>>> 2) Maybe -hostresource? >>> >>> Is ability to cause high latency for other threads really a resource? >> >> The "resource" here is host CPU time. > > Right but then everything we do is a host resource in that sense. > Host network, host disk ... Yes of course. These options control how (and how much) QEMU uses those resources. >> In general, a vCPU with >> KVM_CPU_X86_DISABLE_EXITS will use more host CPU time and block >> overcommitting, just like mlock does for memory. > > What bothers me is that it does not block overcommit as such. > It has a side effect that if something does end up > running on the same CPU, that something will get bad > latency jitter. > > I agree there's similarity here around overcommit. > > That's why I suggested -dedicated as an antonym to -overcommit. > > But I'm fine with -disable-overcommit or -dedicated-host-resource too. Both of those are quite a mouthful. I somewhat prefer "-overcommit" to "-dedicated", though "-hostresource" it's still my favorite mostly because it's the most future-proof. Paolo
