Re: [HACKERS] Execution time.

From: Shiby Thomas <sthomas(at)cise(dot)ufl(dot)edu>
To: "Vadim B(dot) Mikheev" <vadim(at)sable(dot)krasnoyarsk(dot)su>
Cc: The Hermit Hacker <scrappy(at)hub(dot)org>, pgsql-hackers(at)postgreSQL(dot)org
Subject: Re: [HACKERS] Execution time.
Date: 1998-02-04 16:26:11
Message-ID: 199802041626.LAA01859@cise.ufl.edu
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=> > 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

Thanks
--shiby

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