Whit Armstrong <armstrong.whit@xxxxxxxxx> wrote: > But there is no such risk to turning off write barriers? Supposedly not: http://xfs.org/index.php/XFS_FAQ#Q._Should_barriers_be_enabled_with_storage_which_has_a_persistent_write_cache.3F > Did you get a substantial performace boost from disabling write > barriers? like 10x or more like 2x? It made a huge difference on creation and deletion of disk files. Unfortunately we have some procedures which use a cursor and loop through rows calling a function which creates and drops a temporary table. While I would like to see those transactions rewritten to use sane techniques, they run fast enough without the write barriers to be acceptable to the users, which puts the issue pretty low on the priority list. I don't have the numbers anymore, but I'm sure it was closer to 100 times slower than 10 times. In some workloads you might not notice the difference, although I would watch out for checkpoint behavior. -Kevin -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
