On 11/30/2012 07:31 AM, Niels Kristian Schjødt wrote:
In theory what difference should it make to the performance, to have a pool in front of the database, that all my workers and web servers connect to instead of connecting directly? Where is the performance gain coming from in that situation?
If you have several more connections than you have processors, the database does a *lot* more context switching, and among other things, that drastically reduces PG performance. On a testbed, I can get over 150k transactions per second on PG 9.1 with a 1-1 relationship between CPU and client. Increase that to a few hundred, and my TPS drops down to 30k. Simply having the clients there kills performance. -- Shaun Thomas OptionsHouse | 141 W. Jackson Blvd. | Suite 500 | Chicago IL, 60604 312-444-8534 sthomas@xxxxxxxxxxxxxxxx ______________________________________________ See http://www.peak6.com/email_disclaimer/ for terms and conditions related to this email -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
