> I have seen it -- on 8.1 too. On our case it was caused by an insert
> that was doing lots of toast insertions, so it needed to grab the
> extension lock frequently for the toast table; and this was slowed
> down by a largish shared_buffers setting, somehow (8.1 doesn't have lock
> partitioning, so this was expensive). I don't recall details on why
> these were related. If this is your case too, I doubt you'd be able to
> reproduce it in 9.0 (not even in 8.2 which is when lock partitioning was
> introduced).
Thanks, I'll bet that's the case. This is happening on machines with
more RAM, so they've increased shared_buffers.
Now, to get them off 8.1. Been trying for over a year now ...
-- -- Josh Berkus PostgreSQL Experts Inc.
http://www.pgexperts.com