Hello Glyn, Our legacy apps have some permanent tables that they use for tempory data > and constantly clear out, I've kicked the developers and I intend to > eradicate them eventually (the tables, not the developers). >
and what is the problem with this usage? That is a perfectly valid thing to do; PostgreSQL can handle that for centuries; no need to kick the developers :) > These tables are constantly being autovacuumed, approximately once a > minute, it's not causing any problem and seems to be keeping them vacuumed. > > That is the right thing to do. pages: 21 removed, 26 remain > tuples: 2356 removed, 171 remain > system usage: CPU 0.00s/0.00u sec elapsed 0.08 sec > > As you described, that temp-tables get filled and cleared regularly ... that is "insert <a lot of stuff>" "delete <the same stuff again>"; so there are lots of "unused" i.e. deleted tuples, which get recycled by your vacuuming. And that with nearly no CPU usage. Sounds fine to me :) Best wishes, Harald -- GHUM Harald Massa persuadere et programmare Harald Armin Massa Spielberger Straße 49 70435 Stuttgart 0173/9409607 no fx, no carrier pigeon - EuroPython 2009 will take place in Birmingham - Stay tuned!