Bruce Momjian <pgman@candle.pha.pa.us> writes:
> An interesting case is the pg_listener index in commands/async.c. Our
> previous index was by relname/pid. By changing this index to
> pid/relname, I can add index scans based in pid to prevent the many heap
> scans in the file. I am sure there are other places that can be
> improved.
My opinion about that is that the pg_listener operations are better off
with no indexes at all. pg_listener is small and *very* frequently
updated...
regards, tom lane