[lkml]   [2010]   [Apr]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: VM performance issue in KVM guests.
    On Thu, Apr 15, 2010 at 03:33:18PM +0200, Peter Zijlstra wrote:
    > On Thu, 2010-04-15 at 11:18 +0300, Avi Kivity wrote:
    > >
    > > Certainly that has even greater potential for Linux guests. Note that
    > > we spin on mutexes now, so we need to prevent preemption while the lock
    > > owner is running.
    > either that, or disable spinning on (para) virt kernels. Para virt
    > kernels could possibly extend the thing by also checking to see if the
    > owner's vcpu is running.

    I suspect we will need a combination of both approaches, given that we will not
    be able to avoid preempting guests in their critical section always (too long
    critical sections or real-time tasks wanting to preempt). Other idea is to
    gang-schedule VCPUs of the same guest as much as possible?

    - vatsa

     \ /
      Last update: 2010-04-15 18:47    [W:0.019 / U:90.236 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site