On Aug 19, 2013, at 9:55 AM, Dzmitry <dzmitry.nikitsin@xxxxxxxxx> wrote: > No, I am not using pgbouncer, I am using pgpool. > > Total - I have 440 connections to postgres(I have rails application > running on some servers - each application setup 60 connections to DB and > keep if forever(until will not be killed), also I have some machines that > do background processing, that keep connections too). > > Part that do a lot of writes(that update jobs from xml feed every night) - > have 40 threads and keep 40 connections. That's extreme, and probably counter-productive. How many cores do you have on those rails servers? Probably not 64, right? Not 32? 16? 12? 8, even? Assuming <64, what advantage do you expect from 60 connections? Same comment applies to the 40 connections doing the update jobs--more connections than cores is unlikely to be helping anything, and more connections than 2x cores is almost guaranteed to be worse than fewer. Postgres connections are of the heavy-weight variety: process per connection, not thread per connection, not thread-per core event-driven. In particular, I'd worry about work_mem in your configuration. You've either got to set it really low and live with queries going to disk too quickly for sorts and so on, or have it a decent size and have the risk that too many queries at once will trigger OOM. Given your configuration, I wouldn't even start with pgbouncer for connection pooling. I'd first just slash the number of connections everywhere by 1/2, or even 1/4 and see what effect that had. Then as a second step I'd look at where connection pooling might be used effectively. -- Scott Ribe scott_ribe@xxxxxxxxxxxxxxxx http://www.elevated-dev.com/ (303) 722-0567 voice -- Sent via pgsql-admin mailing list (pgsql-admin@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin
