On Saturday March 25 2006 9:55 pm, chris smith wrote: > On 3/26/06, Ed L. <pgsql@xxxxxxxxxxxxx> wrote: > > On Saturday March 25 2006 9:36 pm, Ed L. wrote: > > > I have a performance riddle, hoping someone can point me > > > in a helpful direction. We have a pg 8.1.2 cluster using > > > Apache::Sessions and experiencing simple UPDATEs taking > > > sometimes 30+ seconds to do a very simply update, no > > > foreign keys, no triggers: > > > > The table has 6800 rows over 18000 pages, and is getting a > > minimum of many tens of thousands of updates per day with > > queries like this: > > If you're updating that much, how often are you running > 'analyze'? Are you running autovacuum? How often? I count on the built-in autovacuum to do do analyzes (per 8.1.2 docs). I'm running autovacuum with the following non-default parameters: autovacuum = on autovacuum_naptime = 600 # 10 minutes With our set of 4 DBs, that amounts to once every 40 minutes for the given database. I see "LOG: autovacuum: processing database "xyz"" in the log, but I do not see any analyze/vacuum commands being issued at all (does it log when it analyzes/vacuums?). Thanks, Ed
