I don't have detail perf number for sync io latency now. But a few days ago I did single OSD single io depth benchmark. In short, Firefly > Dumpling > Hammer per op latency. It's great to see Mark's benchmark result! As for pcie ssd, I think ceph can't make full use of it currently for one OSD. We may need to mainly focus on sata-ssd improvments. On Mon, Feb 23, 2015 at 1:09 PM, Gregory Farnum <greg@xxxxxxxxxxx> wrote: > On Tue, Feb 17, 2015 at 9:37 AM, Mark Nelson <mnelson@xxxxxxxxxx> wrote: >> Hi All, >> >> I wrote up a short document describing some tests I ran recently to look at >> how SSD backed OSD performance has changed across our LTS releases. This is >> just looking at RADOS performance and not RBD or RGW. It also doesn't offer >> any real explanations regarding the results. It's just a first high level >> step toward understanding some of the behaviors folks on the mailing list >> have reported over the last couple of releases. I hope you find it useful. > > Do you have any work scheduled to examine the synchronous IO latency > changes across versions? I suspect those are involved with the loss of > performance some users have reported, and I've not heard any > believable theories as to the cause. Since this is the first set of > results pointing that way on hardware available for detailed tests I > hope we can dig into it. And those per-op latencies are the next thing > we'll need to cut down on, since they correspond pretty directly with > CPU costs that we want to scale down! :) > -Greg > -- > 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 -- Best Regards, Wheat -- 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
