On Thu, Apr 21, 2011 at 2:22 AM, Toby Corkindale <toby.corkindale@xxxxxxxxxxxxxxxxxxxx> wrote: > I've done some testing of PostgreSQL on different filesystems, and with > different filesystem mount options. > > I found that xfs and ext4 both performed similarly, with ext4 just a few > percent faster; and I found that adjusting the mount options only gave small > improvements, except for the barrier options. (Which come with a hefty > warning) > > I also tested btrfs, and was disappointed to see it performed *dreadfully* - > even with the recommended options for database loads. > > Best TPS I could get out of ext4 on the test machine was 2392 TPS, but btrfs > gave me just 69! This is appalling performance. (And that was with nodatacow > and noatime set) > > I'm curious to know if anyone can spot anything wrong with my testing? > I note that the speed improvement from datacow to nodatacow was only small - > can I be sure it was taking effect? (Although cat /proc/mounts reported it > had) > > The details of how I was running the test, and all the results, are here: > http://blog.dryft.net/2011/04/effects-of-filesystems-and-mount.html > > I wouldn't run btrfs in production systems at the moment anyway, but I am > curious about the current performance. > (Tested on Ubuntu Server - Maverick - Kernel 2.6.35-28) your nobarrier options are not interesting -- hardware sync is not being flushed. the real numbers are in the 230 range. not sure why brtfs is doing so badly -- maybe try comparing on single disk volume vs raid 0? merlin -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
