Ed L. wrote: > > We are having locking issues in 8.1.2 on HP 11.23 ia64. I'm > trying to better understand how to conclusively identify who is > waiting on who and why. > > We have a series of "select for updates" on our 'sessions' table. > One of those queries is stuck waiting for a "transactionid" > locktype ShareLock. How can I tell what it's actually waiting > for? There should be tuple locks on pg_locks for the transaction that holds the transactionid that your transaction is waiting on. -- Alvaro Herrera http://www.CommandPrompt.com/ PostgreSQL Replication, Consulting, Custom Development, 24x7 support