On 09/08/12 09:58, Mark Nelson wrote:
For what it's worth, with mostly default settings I was seeing about 8MB/s to dell branded samsung SSDs with 4k IOs using rados bench. That was with 256 concurrent client requests. This is definitely something we are working hard on tracking down.
Right (FWIW I think the Dells are actually Toshiba devices - and are pretty good). This is what I get doing the rados bench for 1M and 4K blocks:
$ rados bench -b 1048576 -t 256 -p rbd 100 write Total writes made: 3879 Write size: 1048576 Bandwidth (MB/sec): 38.414 Stddev Bandwidth: 40.157 Max bandwidth (MB/sec): 174 Min bandwidth (MB/sec): 0 Average Latency: 6.57279 Stddev Latency: 6.20373 Max latency: 28.531 Min latency: 0.435691 $ rados bench -b 4096 -t 256 -p rbd 100 write Total writes made: 4851 Write size: 4096 Bandwidth (MB/sec): 0.179 Stddev Bandwidth: 0.378904 Max bandwidth (MB/sec): 3.22266 Min bandwidth (MB/sec): 0 Average Latency: 5.60013 Stddev Latency: 8.18634 Max latency: 22.6542 Min latency: 0.020016 -- 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
