Re: [HACKERS] Execution time.
Marc G. Fournier <scrappy@hub.org>
From: The Hermit Hacker <scrappy@hub.org>
To: Shiby Thomas <sthomas@cise.ufl.edu>
Cc: "Vadim B. Mikheev" <vadim@sable.krasnoyarsk.su>, pgsql-hackers@postgreSQL.org
Date: 1998-02-04T16:38:04Z
Lists: pgsql-hackers
On Wed, 4 Feb 1998, Shiby Thomas wrote: > > => > I invoked postmaster as: > => > postmaster -B 30000 -o "-s -F -S 16384" > => ^^^^^ > => 240M of shared memory ?! > => > Is the size of the hash bucket dependent on the number of buffers available ? > If so, with -B 30000, it might create huge hash buckets and hence the > hash join could degenerate to a nested loops join. Is that possible -- just > checking. What could be good values for -B and -S. The largest table I am > joining is about 60M My production server runs with a -B 256, and a -S 10240