partitioning

we have a realtime manufacturing system that uses messaging to a data
service that uses a very large database we're trying to migrate to
postgres.  key tables in this database have a 6 month retention, and are
quite large, so they are partitioned by week, and we drop the oldest
weeks periodically.   Sometimes, the DROP TABLE's hang, then fail with a
deadlock.

We are getting DROP TABLE deadlocks under the full production workload
which involves 100 or so active database worker processes pretty much
continuously doing transactions in respond to message from the floor.
There are a lot of lookups in the partitioned tables parents that don't
involve the oldest partitions, We've been unable to simulate this in my
lab to date.    I've been unable to get ahold of a log of this event, as
currently production has gone to manually stopping the workers and
running the partition purge twice a month by hand, I'm asking them to
reproduce so I can see whats going on.


this is kind of frustrating, because I'm so far removed from the
problem, and am having problems getting adequate information.



--
john r pierce                            N 37, W 122
santa cruz ca                         mid-left coast