Re: Weird problem that enormous locks

On Wed, Jul 13, 2011 at 9:47 PM, Tony Wang <wwwjfy(at)gmail(dot)com> wrote:
> On Thu, Jul 14, 2011 at 10:35, John R Pierce <pierce(at)hogranch(dot)com> wrote:
> It's a game server, and the queries are updating users' money, as normal.
> The sql is like "UPDATE player SET money = money + 100 where id = 12345".
> The locks were RowExclusiveLock for the table "player" and the indexes. The
> weird thing is there was another ExclusiveLock for the table "player", i.e.
> "player" got two locks, one RowExclusiveLock and one ExclusiveLock.
> In the postgresql documentation
> (http://www.postgresql.org/docs/8.4/static/explicit-locking.html), it's said
> about the  Exclusive "This lock mode is not automatically acquired on user
> tables by any PostgreSQL command."

You need to figure out what part of your app, or maybe a rogue
developer etc is throwing an exclusive lock.