Hello, I'm doing some tests with fio from a qemu 1.2 guest (virtio disk,cache=none), randread, with 4K block size on a small size of 1G (so it can be handle by the buffer cache on ceph cluster)
fio --filename=/dev/vdb -rw=randread --bs=4K --size=1000M --iodepth=40 --group_reporting --name=file1 --ioengine=libaio --direct=1 I can't get more than 5000 iops. RBD cluster is : --------------- 3 nodes,with each node : -6 x osd 15k drives (xfs), journal on tmpfs, 1 mon -cpu: 2x 4 cores intel xeon [email protected] rbd 0.53 ceph.conf journal dio = false filestore fiemap = false filestore flusher = false osd op threads = 24 osd disk threads = 24 filestore op threads = 6 kvm host is : 4 x 12 cores opteron ------------ During the bench: on ceph nodes: - cpu is around 10% used - iostat show no disks activity on osds. (so I think that the 1G file is handle in the linux buffer) on kvm host: -cpu is around 20% used I really don't see where is the bottleneck.... Any Ideas, hints ? Regards, Alexandre -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
