From: Jeff Boes <jboes@nexcerpt.com>
To: pgsql-sql@postgresql.org
Subject: Performance on temp table inserts
Date: Mon, 19 May 2003 15:11:48 -0400
Message-ID: <baba9i$2vi8$1@news.hub.org> (raw)
What factors affect the performance of a temp table insert? On nearly
identical boxes, I have recorded these kinds of statistics:
"INSERT INTO temp_link_checksums VALUES (?)","25957","0.009","245.546"
(That's the statement text, the number of executions, the average, and
the total wallclock time.)
"INSERT INTO temp_link_checksums VALUES (?)","76962","0.041","3184.835"
Box #1 is our "production" server, and actually has more going on during
the day than #2 which is the "test" server. #1 has "shared_buffers" set
to 131072; #2 has it at 250000. Hardware, O/S and PostgreSQL versions are
all identical. Software executing the query (Perl code using DBI) is the
same.
I don't have stats on std-dev for these results; I suppose there could be
an outlying value in the #2 box that dragged down the average. But before
I re-instrument my statistics-gathering code, I thought I'd check to see
if anyone knows how temp tables and shared memory might interact.
--
Jeff Boes vox 269.226.9550 ext 24
Database Engineer fax 269.349.9076
Nexcerpt, Inc. http://www.nexcerpt.com
...Nexcerpt... Extend your Expertise
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To: pgsql-sql@postgresql.org
Cc: jboes@nexcerpt.com
Subject: Re: Performance on temp table inserts
In-Reply-To: <baba9i$2vi8$1@news.hub.org>
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