On Fri, 2008-11-14 at 09:00 -0600, Dan Armbrust wrote: > > There was concurrent access to the table during VACUUMing, so the long > > delay is explainable as long waits for cleanup lock, plus probably > > thrashing the cache with bloated indexes. The CPU overhead per row seems > > OK. We should instrument the wait time during a VACUUM and report that > > also. > Is that a guess? Or something you can tell from the log above? The number of row versions in each index was different after vacuuming. That tells me some writes occurred and I inferred from that that other read-only activity occurred as well. Reads or writes will slow down a VACUUM. Perhaps you have vacuum_cost_delay set also? -- Simon Riggs www.2ndQuadrant.com PostgreSQL Training, Services and Support -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general