hubert depesz lubaczewski <depesz@xxxxxxxxxx> writes: > On Tue, Mar 15, 2011 at 12:13:21AM -0400, Noah Misch wrote: >> What is a typical lifespan for a backend in this system? What sort of >> connection pooling are you using, if any? > quite long, but: > we have n (~ 40 i think) web servers. each webserver has it's own > pgbouncer (in session pooling). > application connects to pgbouncer, issues (usually) single query, and > disconnects. > pgbouncers are set to close oder connections, if unused, after (i think > 2 minutes. (i don't actually have access there). > generally, through the day we see from 400 to 800 connections, mostly > idle, but sometimes it goes much higher (like 1400), and then the > connections are mostly parsing. If the backends are "mostly idle" then it'd be a good idea to set a smaller maximum limit on their number. Idle backends can be a performance risk pre-8.4 because of the cache reset problem Noah pointed to. You'd be better off having pgbouncer delay incoming queries until there's a free backend to pass them to. regards, tom lane -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
