Am 08.11.2012 um 06:42 schrieb Dietmar Maurer <dietmar@xxxxxxxxxxx>: >> I've noticed something really interesting. >> >> I get 5000 iops / VM for rand. 4k writes while assigning 4 cores on a >> 2.5 Ghz Xeon. >> >> When i move this VM to another kvm host with 3.6Ghz i get 8000 iops (still 8 >> cores) when i then LOWER the assigned cores from 8 to 4 i get >> 14.500 iops. If i assign only 2 cores i get 16.000 iops... >> >> Why does less kvm cores mean more speed? > > There is a serious bug in the kvm vhost code. Do you use virtio-net with vhost? > > see: http://lists.nongnu.org/archive/html/qemu-devel/2012-11/msg00579.html > > Please test using the e1000 driver instead. Why is vhost net driver involved here at all? Kvm guest only uses ssh here. Stefan -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
