On Sun, Aug 17, 2014 at 03:35:39PM +0300, Razya Ladelsky wrote: > > > > > > Hi Michael, > > > > > > Sorry for the delay, had some problems with my mailbox, and I realized > > > > just now that > > > my reply wasn't sent. > > > The vm indeed ALWAYS utilized 100% cpu, whether polling was enabled or > > > > not. > > > The vhost thread utilized less than 100% (of the other cpu) when > polling > > > was disabled. > > > Enabling polling increased its utilization to 100% (in which case both > > > > cpus were 100% utilized). > > > > Hmm this means the testing wasn't successful then, as you said: > > > > The idea was to get it 100% loaded, so we can see that the polling is > > getting it to produce higher throughput. > > > > in fact here you are producing more throughput but spending more power > > to produce it, which can have any number of explanations besides polling > > improving the efficiency. For example, increasing system load might > > disable host power management. > > > > Hi Michael, > I re-ran the tests, this time with the "turbo mode" and "C-states" > features off. > No Polling: > 1 VM running netperf (msg size 64B): 1107 Mbits/sec > Polling: > 1 VM running netperf (msg size 64B): 1572 Mbits/sec > > > > > > > > As you can see from the new results, the numbers are lower, > but relatively (polling on/off) there's no change. > Thank you, > Razya That was just one example. There many other possibilities. Either actually make the systems load all host CPUs equally, or divide throughput by host CPU. > > > > > > > > > > > -- > > > > MST > > > > > > -- > > 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 > > _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
