Re: [PERFORM] How can I find the source of postgresql per-connection memory leaks?
On 01/12/2017 09:08 AM, Eric Jensen wrote: I'm using postgresql 9.5.4 on amazon RDS with ~1300 persistent connections from rails 4.2 with "prepared_statements: false". Over the enter image description here PostgreSQL on RDS is a closed product. My recommendation would be to contact Amazon support. They are likely to be able to provide you with better support. Sincerely, JD -- Command Prompt, Inc. http://the.postgres.company/ +1-503-667-4564 PostgreSQL Centered full stack support, consulting and development. Everyone appreciates your honesty, until you are honest with them. Unless otherwise stated, opinions are my own. -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
[PERFORM] How can I find the source of postgresql per-connection memory leaks?
I'm using postgresql 9.5.4 on amazon RDS with ~1300 persistent connections from rails 4.2 with "prepared_statements: false". Over the course of hours and days, the "Freeable Memory" RDS stat continues to go down indefinitely but jumps back up to a relatively small working set every time we reconnect (restart our servers). If we let it go too long, it goes all the way to zero and the database instance really does start to go into swap and eventually fail. Subtracting the freeable memory over days from the peaks when we restart we see that there are 10's of MB per connection on average. [image: enter image description here] Digging into the per-pid RSS from enhanced monitoring, we see the same slow growth on example connection pids but the total RSS seems to just be a proxy for actual memory usage per connection ( https://www.depesz.com/2012/06/09/how-much-ram-is-postgresql-using/). [image: enter image description here] How can I either: Change the default.postgres9.5 parameters below to avoid unbounded memory growth per-connection Determine what queries cause this unbounded growth and change them to prevent it Determine what type of buffering/caching is causing this unbounded growth so that I can use that to do either of the above [image: enter image description here]
