Try comparing results from something like this test [global] ioengine=posixaio invalidate=1 ramp_time=30 iodepth=1 runtime=180 time_based direct=1 filename=/mnt/cephfs/ssd/fio-bench.img [write-4k-seq] stonewall bs=4k rw=write #write_bw_log=sdx-4k-write-seq.results #write_iops_log=sdx-4k-write-seq.results [randwrite-4k-seq] stonewall bs=4k rw=randwrite #write_bw_log=sdx-4k-randwrite-seq.results #write_iops_log=sdx-4k-randwrite-seq.results [read-4k-seq] stonewall bs=4k rw=read #write_bw_log=sdx-4k-read-seq.results #write_iops_log=sdx-4k-read-seq.results [randread-4k-seq] stonewall bs=4k rw=randread #write_bw_log=sdx-4k-randread-seq.results #write_iops_log=sdx-4k-randread-seq.results [rw-4k-seq] stonewall bs=4k rw=rw #write_bw_log=sdx-4k-rw-seq.results #write_iops_log=sdx-4k-rw-seq.results [randrw-4k-seq] stonewall bs=4k rw=randrw #write_bw_log=sdx-4k-randrw-seq.results #write_iops_log=sdx-4k-randrw-seq.results [write-128k-seq] stonewall bs=128k rw=write #write_bw_log=sdx-128k-write-seq.results #write_iops_log=sdx-128k-write-seq.results [randwrite-128k-seq] stonewall bs=128k rw=randwrite #write_bw_log=sdx-128k-randwrite-seq.results #write_iops_log=sdx-128k-randwrite-seq.results [read-128k-seq] stonewall bs=128k rw=read #write_bw_log=sdx-128k-read-seq.results #write_iops_log=sdx-128k-read-seq.results [randread-128k-seq] stonewall bs=128k rw=randread #write_bw_log=sdx-128k-randread-seq.results #write_iops_log=sdx-128k-randread-seq.results [rw-128k-seq] stonewall bs=128k rw=rw #write_bw_log=sdx-128k-rw-seq.results #write_iops_log=sdx-128k-rw-seq.results [randrw-128k-seq] stonewall bs=128k rw=randrw #write_bw_log=sdx-128k-randrw-seq.results #write_iops_log=sdx-128k-randrw-seq.results [write-1024k-seq] stonewall bs=1024k rw=write #write_bw_log=sdx-1024k-write-seq.results #write_iops_log=sdx-1024k-write-seq.results [randwrite-1024k-seq] stonewall bs=1024k rw=randwrite #write_bw_log=sdx-1024k-randwrite-seq.results #write_iops_log=sdx-1024k-randwrite-seq.results [read-1024k-seq] stonewall bs=1024k rw=read #write_bw_log=sdx-1024k-read-seq.results #write_iops_log=sdx-1024k-read-seq.results [randread-1024k-seq] stonewall bs=1024k rw=randread #write_bw_log=sdx-1024k-randread-seq.results #write_iops_log=sdx-1024k-randread-seq.results [rw-1024k-seq] stonewall bs=1024k rw=rw #write_bw_log=sdx-1024k-rw-seq.results #write_iops_log=sdx-1024k-rw-seq.results [randrw-1024k-seq] stonewall bs=1024k rw=randrw #write_bw_log=sdx-1024k-randrw-seq.results #write_iops_log=sdx-1024k-randrw-seq.results [write-4096k-seq] stonewall bs=4096k rw=write #write_bw_log=sdx-4096k-write-seq.results #write_iops_log=sdx-4096k-write-seq.results [randwrite-4096k-seq] stonewall bs=4096k rw=randwrite #write_bw_log=sdx-4096k-randwrite-seq.results #write_iops_log=sdx-4096k-randwrite-seq.results [read-4096k-seq] stonewall bs=4096k rw=read #write_bw_log=sdx-4096k-read-seq.results #write_iops_log=sdx-4096k-read-seq.results [randread-4096k-seq] stonewall bs=4096k rw=randread #write_bw_log=sdx-4096k-randread-seq.results #write_iops_log=sdx-4096k-randread-seq.results [rw-4096k-seq] stonewall bs=4096k rw=rw #write_bw_log=sdx-4096k-rw-seq.results #write_iops_log=sdx-4096k-rw-seq.results [randrw-4096k-seq] stonewall bs=4096k rw=randrw #write_bw_log=sdx-4096k-randrw-seq.results #write_iops_log=sdx-4096k-randrw-seq.results -----Original Message----- From: Dave.Chen@xxxxxxxx [mailto:Dave.Chen@xxxxxxxx] Sent: woensdag 14 november 2018 5:21 To: ceph-users@xxxxxxxxxxxxxx Subject: Benchmark performance when using SSD as the journal Hi all, We want to compare the performance between HDD partition as the journal (inline from OSD disk) and SSD partition as the journal, here is what we have done, we have 3 nodes used as Ceph OSD, each has 3 OSD on it. Firstly, we created the OSD with journal from OSD partition, and run “rados bench” utility to test the performance, and then migrate the journal from HDD to SSD (Intel S4500) and run “rados bench” again, the expected result is SSD partition should be much better than HDD, but the result shows us there is nearly no change, The configuration of Ceph is as below, pool size: 3 osd size: 3*3 pg (pgp) num: 300 osd nodes are separated across three different nodes rbd image size: 10G (10240M) The utility I used is, rados bench -p rbd $duration write rados bench -p rbd $duration seq rados bench -p rbd $duration rand Is there anything wrong from what I did? Could anyone give me some suggestion? Best Regards, Dave Chen _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com