Every 60 minutes, a vacuum process starts on my master node.  Since I am not running AutoVacuum at all, and have no cron jobs, that only leaves Slony ...

The problem is that this vacuum is now taking over 5 minutes per hour to complete, and makes the system virtually unusable (CPU load goes to 400%).  I don't understand why this should happen -- the Slony replication set isn't very large, and the only tables that change much are log tables that are only appended.  And this is the master, not the slave...

Questions:

1. Does Slony run vacuum every hour?
2. If so, is it a requirement?
3. Any ideas why the vacuum is taking longer and longer?
4.I don't even know what else to ask???

This is PG 8.1, Slony 1.2.9.  (I know, I need to upgrade, we're getting new servers soon and will upgrade then.)


Thanks,
Craig