On Fri, Sep 11, 2009 at 10:36 AM, Bruce Rogers <brogers@xxxxxxxxxx> wrote: > Also, when I did a simple experiment with vcpu overcommitment, I was surprised how quickly performance suffered (just bringing a Linux vm up), since I would have assumed the additional vcpus would have been halted the vast majority of the time. On a 2 proc box, overcommitment to 8 vcpus in a guest (I know this isn't a good usage scenario, but does provide some insights) caused the boot time to increase to almost exponential levels. At 16 vcpus, it took hours to just reach the gui login prompt. I'd guess (and hope!) that having many 1- or 2-cpu guests won't kill performance as sharply as having a single guest with more vcpus than the physical cpus available. have you tested that? -- Javier -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
