Premature optimization is the root of all evil ;-). Unless you've done some profiling and can show that this is a hot spot, making it more complicated isn't the thing to be doing now.
I'm thinking of how our system uses/abuses notifies, and began wondering if several thousand backends listening with a large queue would perform decently behind a linear search. At this point, I have no data either way; only an assumption based off being burnt by sequential scans in the past ;)
-- Andrew Chernow eSilo, LLC every bit counts http://www.esilo.com/ -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers