On Tue, Nov 25, 2008 at 07:17:20PM -0800, John Smith wrote: > I have a pg instance with 700GB of data, almost all of which is in one > table. When I PREPARE and then COMMIT PREPARED a transaction that > reads & writes to a large fraction of that data (about 10%, > effectively randomly chosen rows and so every file in the table is > modified), the COMMIT PREPARED sometimes takes a very long time--2 to > 5 minutes. Is this expected? Is it possible for the commit to hang > waiting on some lock for this long? I haven't yet been able to examine > pg_locks during this 5 minute delay. There is very little > concurrency--only a couple of open sessions--when the COMMIT PREPARED > is issued. You could be I/O bound. Have a look at iostat and sar. A -- Andrew Sullivan ajs@xxxxxxxxxxxxxxx -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
