Hi: On Sun, Feb 16, 2014 at 1:02 AM, Antman, Jason (CMG-Atlanta) <Jason.Antman@xxxxxxxxxx> wrote: > ones to expire out of cache. I.e. we have hardware with 192G of RAM. If > each database is only queried, say, for 10 seconds out of each 5 minute > interval, how do we maximize resource utilization / squeeze as many DBs > onto as few pieces of hardware as possible. If we spin up VMs every > morning, we're back to where we are now, with one postgres sever per VM, > and a large amount of physical memory being used up by virtualization > overhead (guest OS) and idle postgres processes. If you run many instances on the same machine, and make sure this 10 seconds are connection time ( beware of connection pools ) memory reuse is between processes, not VMs, which OS are currently very good at. You should try to minimize the shared-buffers used, as they are tied per-instance, but it will help. I say this because my devs have the nasty having of running their single user test environments with heavy multiuser setups for the connection pool ( something like minimum 8 connections, leave up to 10 free if unused, which, given they only use 1 on tests, leads to 7 permanently unused backends, plus one scarcely used but always resident ). Francisco Olarte. -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
