On Thu, Jul 5, 2012 at 8:50 PM, Alexandre DERUMIER <aderumier@xxxxxxxxx> wrote: > Hi, > Stefan is on vacation for the moment,I don't know if he can reply you. > > But I can reoly for him for the kvm part (as we do same tests together in parallel). > > - kvm is 1.1 > - rbd 0.48 > - drive option rbd:pool/volume:auth_supported=cephx;none;keyring=/etc/pve/priv/ceph/ceph.keyring:mon_host=X.X.X.X"; > -using writeback > > writeback tuning in ceph.conf on the kvm host > > rbd_cache_size = 33554432 > rbd_cache_max_age = 2.0 > > benchmark use in kvm guest: > fio --filename=$DISK --direct=1 --rw=randwrite --bs=4k --size=200G --numjobs=50 --runtime=90 --group_reporting --name=file1 > > results show max 14000io/s with 1 vm, 7000io/s by vm with 2vm,... > so it doesn't scale > > (bench is with directio, so maybe writeback cache don't help) > > hardware for ceph , is 3 nodes with 4 intel ssd each. (1 drive can handle 40000io/s randwrite locally) I'm interested in figuring out why we aren't getting useful data out of the admin socket, and for that I need the actual configuration files. It wouldn't surprise me if there are several layers to this issue but I'd like to start at the client's endpoint. :) Regarding the random IO, you shouldn't overestimate your storage. Under plenty of scenarios your drives are lucky to do more than 2k IO/s, which is about what you're seeing.... http://techreport.com/articles.x/22415/9 -Greg -- 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
