Dennis Seran wrote:
> - Client B again prompts the command pg_try_advisory_lock_shared(12345) in
> an attempt to reobtain the shared lock(12345) but returns false and fails to
> obtain the shared lock (SHOULDN'T THIS CLIENT BE ABLE TO OBTAIN THE SHARED
> LOCK?)
No; it gets to sleep until after client C has released the exclusive
lock. Otherwise a constant stream of shared lockers would starvate
exclusive lockers.
> - The above result happens when all 3 clients are on the same machine. If
> the same steps were followed, but this time with clients A and B on a RHEL
> machine and the client C and the server on an XP machine, the result is a
> bit different. The above step results in Client B going into the queue as
> well as Client C even though Client A currently holds the shared lock.
> (AGAIN, SHOULDN'T THIS CLIENT BE ABLE TO OBTAIN THE SHARED LOCK?)
I think this sounds like a bug.
--
Alvaro Herrera http://www.CommandPrompt.com/
PostgreSQL Replication, Consulting, Custom Development, 24x7 support
