We're running PostgreSQL on Windows Server 2008 (on Amazon EC2), with about 40 databases. When we first launch Postgres, it doesn't use much memory, but over time, the memory usage of ONE of the postgres.exe processes grows (all of the other remain at about 6 MB) until the system runs out of memory. This happens over the course of a few weeks. Right now, the postgres.exe process is using about 1.9 GB, but it will grow to about 2.3 GB eventually (which will max out the memory usage on the server), at which point we have to restart the Postgres service.
I realize this depends on a lot of factors that I'm not describing here, but what are some potential causes? Our postgresql.conf has not been changed from the default, which I understand has very conservative settings. Is this the expected memory usage? If our server had more memory, would it stabilize at some point?