I knew I read the acronym in a pdf somewhere (something from '08 I think), but I couldn't find it when I needed it, thanks. Everything was running 3.1-rc1, I checked the kernel source before building and it already included the following patches, so I assumed I was good on the readahead thing. https://patchwork.kernel.org/patch/1001462/ https://patchwork.kernel.org/patch/1001432/ On Wed, Aug 24, 2011 at 10:46 AM, Sage Weil <sage@xxxxxxxxxxxx> wrote: > On Wed, 24 Aug 2011, Gregory Farnum wrote: >> On Wed, Aug 24, 2011 at 8:29 AM, Marcus Sorensen <shadowsor@xxxxxxxxx> wrote: >> > Just thought I'd share this basic testing I did, comparing cephfs 0.32 >> > on 3.1-rc1 to nfs as well as rbd to iscsi. I'm sure you guys see a lot >> > of this. Any feedback would be appreciated. >> > >> > The data is here: >> > >> > http://learnitwithme.com/wp-content/uploads/2011/08/ceph-nfs-iscsi-benchmarks.ods >> > >> > and the writeup is here: >> > >> > http://learnitwithme.com/?p=303 >> >> We see less of it than you'd think, actually. Thanks! >> >> To address a few things specifically >> Ceph is both the name of the project and of the POSIX-compliant >> filesystem. RADOS stands for Reliable Autonomous Distributed Object >> Store. Apparently we should publish this a bit more. :) >> >> Looks like most of the differences in your tests have to do with our >> relatively lousy read performance -- this is probably due to lousy >> readahead, which nobody's spent a lot of time optimizing as we focus >> on stability. Sage made some improvements a few weeks ago but I don't >> remember what version of stuff they ended up in. :) (Optimizing >> cross-server reads is hard!) > > The readahead improvements are in the 'master' branch of ceph-client.git, > and will go upstream for Linux 3.2-rc1 (I just missed the 3.1-rc1 cutoff). > In my tests I was limited by the wire speed with these patches. I'm > guessing you were using 3.0 or earlier kernel? > > The file copy test was also surprising. I think there is a regression > there somewhere, taking a look. > > sage > > -- 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
