Hi, all: I am doing some benchmark of rbd. The platform is on a NAS storage. CPU: Intel E5640 2.67GHz Memory: 192 GB Hard Disk: SATA 250G * 1, 7200 rpm (H0) + SATA 1T * 12 , 7200rpm (H1~ H12) RAID Card: LSI 9260-4i OS: Ubuntu12.04 with Kernel 3.2.0-24 Network: 1 Gb/s We create 12 OSD on H1 ~ H12 with the journal is put on H0. We also create 3 MON in the cluster. In briefly, we setup a ceph cluster all-in-one, with 3 monitors and 12 OSD. The benchmark tool we used is fio 2.0.3. We had 7 basic test case 1) sequence write with bs=64k 2) sequence read with bs=64k 3) random write with bs=4k 4) random write with bs=16k 5) mix read/write with bs=4k 6) mix read/write with bs=8k 7) mix read/write with bs=16k We create several rbd with different object size for the benchmark. 1. size = 20G, object size = 32KB 2. size = 20G, object size = 512KB 3. size = 20G, object size = 4MB 4. size = 20G, object size = 32MB We have some conclusion after the benchmark. a. We can get better performance of sequence read/write when the object size is bigger. Seq-read Seq-write 32 KB 23 MB/s 690 MB/s 512 KB 26 MB/s 960 MB/s 4 MB 27 MB/s 1290 MB/s 32 MB 36 MB/s 1435 MB/s b. There is no obvious influence for random read/write when the object size is different. All the result are in a range not more than 10%. rand-write-4K rand-write-16K mix-4K mix-8k mix-16k 881 iops 564 iops 1462 iops 1127 iops 1044 iops c. It we change the environment, for every 3 hard drive, we bind them together by RAID0. (LSI 9260-4i RAID card) So the ceph cluster becomes 3 MONs and 4 OSD (3T for each) We can get better performance on all items, around 10% ~ 20% enhancement. d. If we change H0 to a SSD device, and we also put all journal on it. We can get better performance on sequence-write. It would reach 135MB/s. However, there are no different for other test items. We want to check with you, if all the conclusion are reasonable for you? Or any seems strange? Thanks! ==== Here is some data if I use command provided by rados. rados -p rbd bench 120 write -t 8 Total time run: 120.751713 Total writes made: 930 Write size: 4194304 Bandwidth (MB/sec): 30.807 Average Latency: 1.03807 Max latency: 2.63197 Min latency: 0.205726 [INF] bench: wrote 1024 MB in blocks of 4096 KB in 13.219819 sec at 79318 KB/sec -- 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