On 10/08/2013 08:36 PM, Marc Zyngier wrote: >>> Just gave it a go, and the results are slightly (but consistently) >>> worse. Over 10 runs: >>> >>> Without RELAX_INTERCEPT: Average run 3.3623s >>> With RELAX_INTERCEPT: Average run 3.4226s >>> >>> Not massive, but still noticeable. Any clue? >> >> Is it a 4x overcommit? Probably we would have hit the code >> overhead if it were small guests. > > Only 2x overcommit (dual core host, quad vcpu guests). Okay. quad vcpu seem to explain. > >> RELAX_INTERCEPT is worth enabling for large guests with >> overcommits. > > I'll try something more aggressive as soon as I get the time. What do > you call a large guest? So far, the hard limit on ARM is 8 vcpus. > Okay. I was referring to guests >= 32 vcpus. May be 8vcpu guests with 2x/4x is worth trying. If we still do not see benefit, then it is not worth enabling. _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/cucslists/listinfo/kvmarm
