I am trying to locate the source of some deadlocks that have started cropping up recently, with little success, and I have a question regarding the message that accompanies them. The message my application gets is like this: Process 244 waits for ShareLock on transaction 39523645; blocked by process 74242. Process 74242 waits for ShareLock on tuple (65,2) of relation 16708 of database 16386; blocked by process 244. But in investigating various places in my code that could be relevant, and executing the statements manually, my deadlock messages always look like this: Process 38158 waits for ShareLock on transaction 15691; blocked by process 38160. Process 38160 waits for ShareLock on transaction 15698; blocked by process 38158. The difference I'm asking about is that my artificial ones always involve waiting on a transaction, while the ones from the real application always involve one transaction wait and one tuple wait. The first question is, is there any significance to this difference? If so, the second question is, what is it? :) In looking at some code in heapam.c, I see the following comment that sorta kinda sounds like maybe there are three parties involved, with two of them waiting on a locked tuple? * Acquire tuple lock to establish our priority for the tuple. * LockTuple will release us when we are next-in-line for the tuple. Thanks for any help, Clarence
