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    SubjectRe: [PATCH v3 0/3] KVM: Yield to IPI target if necessary
    2019-05-30 09:05+0800, Wanpeng Li:
    > The idea is from Xen, when sending a call-function IPI-many to vCPUs,
    > yield if any of the IPI target vCPUs was preempted. 17% performance
    > increasement of ebizzy benchmark can be observed in an over-subscribe
    > environment. (w/ kvm-pv-tlb disabled, testing TLB flush call-function
    > IPI-many since call-function is not easy to be trigged by userspace
    > workload).

    Have you checked if we could gain performance by having the yield as an
    extension to our PV IPI call?

    It would allow us to skip the VM entry/exit overhead on the caller.
    (The benefit of that might be negligible and it also poses a
    complication when splitting the target mask into several PV IPI
    hypercalls.)

    Thanks.

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