On Mon, Jun 02, 2008 at 09:38:29AM -0400, Tom Lane wrote: > That's not very surprising at all: a backend might have to write out a > dirty buffer in order to reclaim the buffer for re-use, and which > database the page is from doesn't enter into that. > What does seem surprising is that it's had to do that quite a lot. > Is this an old PG version without a bgwriter process? In a properly > functioning recent release, I'd expect only the bgwriter to have a > really eclectic mix of open files. # select version(); version ----------------------------------------------------------------------------------------------------------------------- PostgreSQL 8.2.7 on x86_64-unknown-linux-gnu, compiled by GCC gcc (GCC) 4.1.2 20061115 (prerelease) (Debian 4.1.1-21) (1 row) # select name, setting from pg_settings where name ~ 'bgw'; name | setting -----------------------+--------- bgwriter_all_maxpages | 5 bgwriter_all_percent | 0.333 bgwriter_delay | 200 bgwriter_lru_maxpages | 5 bgwriter_lru_percent | 1 (5 rows) should i show any more information? regards, depesz