> -----Original Message----- > From: [email protected] [mailto:ceph-devel- > [email protected]] On Behalf Of Haomai Wang > > > This is so because you use SimpleMessenger, which can't handle small I/O > well. > > Indeed, threads are problematic with it, as well as memory allocation. > > I did some benchmarking some time ago and the gist of it is that you > > could try going for AsyncMessenger and see if it helps. You can also see my > results here: > > http://stuff.predictor.org.pl/chunksize.xlsx > > From there you can see that most of the time of small I/Os in > > SimpleMessenger Is spent in tcmalloc code, and also there's a > > performance drop around 64k Blocksize in Async Messenger. > > > > Thanks for your benchmark, I submit new performance enhanced patchset > for AsyncMessenger. It should solve original stress test performance > degraded problem :-)
Thanks! I'll check it out next week and hopefully got some results to share on Wednesday. With best regards / Pozdrawiam Piotr Dałek
