pg_locks doesn't check for interrupts?

Hackers,

Since querying pg_locks can be intrusive due to needing to lock the lock
partitions, when I'm collecting data about locks I generally put a
statement_timeout on it.  However, I'm noticing that this
statement_timeout appears to be completely ignored; I've seen this query
run for up to 10 minutes* when the database is heavily loaded.  This it
seems likely to me that the functions under pg_locks aren't checking for
interrupts.  Anybody checked this already?

(yes, when a 64,000 item lock table is mostly full of locks, queries
against pg_locks *can* take 10 minutes)

-- 
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com