Josh Berkus wrote: > Hackers, > > I'm looking at a couple of high-transaction-rate and high-FK-conflict > rate servers where pg_multixact has grown to be more than 1GB in size. > One such server doesn't appear to be having any notable issues with > vacuuming, and the oldest mxid on the system is about 47m old. VACUUM > FREEZEing the oldest databases did not cause the pg_multixact dir to get > smaller --- it may have even caused it to get larger. > > Why would pg_multixact not be truncating? Does it never truncate files > with aborted multixacts in them? Might we have another multixact bug?
Have a look at the MultiXactId values in pg_controldata, datminmxid in pg_database, and relminmxid in pg_class. They should advance as you VACUUM FREEZE. If it's stuck at 1, you might be in pg_upgrade trouble if you used 9.3.4 or earlier to upgrade. -- Álvaro Herrera http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
