On Mon, Jun 29, 2020 at 03:03:20PM +0200, Paolo Bonzini wrote: > On 29/06/20 13:31, Roman Bolshakov wrote: > > I implemented what you proposed using VMX-preemption timer in Pin-based > > controls and regular hv_vcpu_run(). It works fine without noticable > > regressions, I'll send that in v2. > > > > hv_vcpu_run_until() was also evaluated on macOS 10.15.5 but it degrades > > VM performance significantly compared to explicit setting of > > VMX-preepmtion timer value and hv_vcpu_run(). The performance issue was > > observed on Broadwell-based MacBook Air and Ivy Bridge-based MacBook > > Pro. > > > > macOS 11.0 Beta deprecated hv_vcpu_run() and introduced a special > > declaration for hv_vcpu_run_until(), that's not available 10.15 - > > HV_DEADLINE_FOREVER (UINT64_MAX, which is bigger than maximum value of > > VMX-preeemption counter). Perhaps the performance issue is addressed > > there. > > Possibly. I'm worried that the preemption-timer trick will fail to run > there, but we'll see. >
Well, I've got new VM-exits (caused by zero preemption timer) on either of my laptops. -Roman
