On Mon, Aug 29, 2011 at 2:38 PM, Merlin Moncure <mmoncure@xxxxxxxxx> wrote: > On Mon, Aug 29, 2011 at 3:36 PM, Lonni J Friedman <netllama@xxxxxxxxx> wrote: >> I have several Linux-x68_64 based dedicated PostgreSQL servers where >> I'm experiencing significant swap usage growth over time. All of them >> have fairly substantial amounts of RAM (not including swap), yet the >> amount of swap that postgres is using ramps up over time and >> eventually hurts performance badly. In every case, simply restarting >> postgresql frees up all the swap in use (until it ramps up again >> later). I'm assuming that I have at least one postgresql.conf >> parameter set wrong, but I'm not sure which. I read that >> (max_connections * work_mem) should never exceed physical RAM, and if >> that's accurate, then I suspect that's the root of my problem on >> systemA (below). However, I'd like confirmation before I start >> tweaking things, as one of these servers is in production, and I can't >> easily tweak settings to experiment (plus this problem takes a few >> weeks before swapping gets bad enough to impact performance). > > using any C code in the backend? this includes 3rd party libraries > which link in C, including postgis, pljava, xml2, etc. Any features > being used not included in the standard core distribution are > interesting. Nope, nothing like that. They're fairly generic setups, with nothing added that isn't part of the core distribution. > > How long do your database connections stay open? forever? If yes, is > memory distributed semi-evenly across all postgres processes or only > to particular ones? If no, do you see excessive consumption with the > non user backends like the stats collector, etc? Nope, nothing is forever, everything is a fairly brief connection (a few seconds, tops, with most under 1s). Although I do have pgbouncer sitting in front of systemA to serve as a connection pooler. > > Anything else running on these boxes? Application server? Anything > written in java? Nothing. They're all 100% dedicated to postgres, and don't run anything else beyond the basic OS level stuff (crond, etc). -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
