Hi list, today while testing btrfs i discovered a very poor osd performance using kernel 3.4.
Underlying FS is XFS but it is the same with btrfs. 3.0.30: ~# rados -p data bench 10 write -t 16 Maintaining 16 concurrent writes of 4194304 bytes for at least 10 seconds. sec Cur ops started finished avg MB/s cur MB/s last lat avg lat 0 0 0 0 0 0 - 0 1 16 41 25 99.9767 100 0.586984 0.447293 2 16 71 55 109.979 120 0.934388 0.488375 3 16 99 83 110.647 112 1.15982 0.503111 4 16 130 114 113.981 124 1.05952 0.516925 5 16 159 143 114.382 116 0.149313 0.510734 6 16 188 172 114.649 116 0.287166 0.52203 7 16 215 199 113.697 108 0.151784 0.531461 8 16 242 226 112.984 108 0.623478 0.539896 9 16 265 249 110.651 92 0.50354 0.538504 10 16 296 280 111.984 124 0.155048 0.542846 Total time run: 10.776153 Total writes made: 297 Write size: 4194304 Bandwidth (MB/sec): 110.243 Average Latency: 0.577534 Max latency: 1.85499 Min latency: 0.091473 3.4: ~# rados -p data bench 10 write -t 16 Maintaining 16 concurrent writes of 4194304 bytes for at least 10 seconds. sec Cur ops started finished avg MB/s cur MB/s last lat avg lat 0 0 0 0 0 0 - 0 1 16 40 24 95.9794 96 0.393196 0.455936 2 16 68 52 103.983 112 0.835652 0.517297 3 16 85 69 91.9849 68 1.00535 0.493058 4 16 96 80 79.9869 44 0.096564 0.577948 5 16 103 87 69.5879 28 0.092722 0.589147 6 16 117 101 67.3216 56 0.222175 0.675334 7 16 130 114 65.1321 52 0.15677 0.623806 8 16 144 128 63.9896 56 0.089157 0.56746 9 16 144 128 56.8794 0 - 0.56746 10 16 144 128 51.1912 0 - 0.56746 11 16 144 128 46.5373 0 - 0.56746 12 16 144 128 42.6591 0 - 0.56746 13 16 144 128 39.3776 0 - 0.56746 14 16 144 128 36.5649 0 - 0.56746 15 16 144 128 34.1272 0 - 0.56746 16 16 145 129 32.2443 0.5 11.3422 0.650985 Total time run: 16.193871 Total writes made: 145 Write size: 4194304 Bandwidth (MB/sec): 35.816 Average Latency: 1.78467 Max latency: 14.4744 Min latency: 0.088753 Stefan -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html