On Wed, Aug 3, 2011 at 8:57 AM, Michael Graham <mgraham@xxxxxxxxx> wrote: > On Wed, 2011-08-03 at 10:17 -0400, Tom Lane wrote: >> Michael Graham <mgraham@xxxxxxxxx> writes: >> > Would my applications >> > constant polling of the queue mean that the lock could not be easily >> > obtained? >> >> Very possible, depending on what duty cycle is involved there. > > Hmm. The clients aren't that aggressive, especially when they failed to > find data on a previous select, there are 4 clients, they each poll > every 10 seconds and the select runs in <1ms. > > It might be worth noting that they don't ever disconnect from the > server, but I assume that is not an issue for getting the > AccessExclusiveLock on the table? > > My worry at the moment is that because the table is so large the vacuum > takes a very long time to run (one has been running for 5hrs) and I > assume it will continue to run until it is able to get the > AccessExclusiveLock is so desperately wants. Assuming you have the spare IO look at making autovacuum more aggressive. Reduce naptime and increase cost -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
