On 19/01/2017 18:01, Stefan Hajnoczi wrote: >>> This is a big and somewhat risky change. Have you run any performance >>> benchmarks? >> >> Not recently; I ran them a year ago and there was no measurable difference. > > Good, please re-run for the final version.
Done, went better than expected. :) base 4k-1 null READ: io=6646.8MB, aggrb=226852KB/s, minb=226852KB/s, maxb=226852KB/s, mint=30000msec, maxt=30000msec 4k-1 nvme READ: io=3086.4MB, aggrb=105342KB/s, minb=105342KB/s, maxb=105342KB/s, mint=30001msec, maxt=30001msec 4k-32 nvme READ: io=14246MB, aggrb=486241KB/s, minb=486241KB/s, maxb=486241KB/s, mint=30001msec, maxt=30001msec patched: 4k-1 null READ: io=7044.5MB, aggrb=240436KB/s, minb=240436KB/s, maxb=240436KB/s, mint=30000msec, maxt=30000msec 4k-1 nvme READ: io=3463.3MB, aggrb=118208KB/s, minb=118208KB/s, maxb=118208KB/s, mint=30001msec, maxt=30001msec 4k-32 nvme READ: io=15217MB, aggrb=519378KB/s, minb=519378KB/s, maxb=519378KB/s, mint=30001msec, maxt=30001msec null is null-co://, nvme is a fast (180kIOPS on bare-metal) NVMe SSD. So it seems to be some 5-10% faster. No idea why so I would not give too much importance on the numbers, but at least it's not worse. Paolo
