On Sat, Apr 13 2013 at 12:09pm -0400, Joe Thornber <thornber@xxxxxxxxxx> wrote: > Hi Darrick, > > On Thu, Apr 11, 2013 at 12:22:39AM -0700, Darrick J. Wong wrote: > > Hi all, > > > > Lately I've been having some fun playing with bcache, dmcache, and enhanceio. > > I pushed some tweaks to the mq policy today to my thin-dev tree. They > show some improvements to these fio based tests. > > In addition I've written a blog post trying to explain what's going on in dm-cache: > http://device-mapper.org/blog/2013/04/13/benchmarking-dm-cache-with-fio/ Darrick, Joe has a few other dm-cache-target.c changes in his thin-dev branch that are required in order to realize the gains from his mq changes. I haven't yet isolated which changes are important but if I just use the 3.9-rc6's dm-cache-tagret.c with thin-dev's mq changes I cannot reproduce the improved performance Joe mentions in his blog post. Also, even before these changes I wasn't able to reproduce your dm-cache results (either the spike in performance or the inconsistencies you saw across runs). BTW, I have added 'test_fio_database_funtime' to both the cache and bcache testsuites in my thinp-test-suite repo (master branch): git://github.com/snitm/thinp-test-suite.git You'd run it with somwthing like: ./run_tests --profile mix_fio --suite cache -n /test_fio_database_funtime/ or ./run_tests --profile mix_fio --suite bcache -n /test_fio_database_funtime/ I've been testing against the v3.9-rc6 kernel with Jens' for-next bcache code merged in, see 'thin-dev-bcache' branch of my linux repo: git://github.com/snitm/linux.git -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
