pgsql: Revert ill-considered change of index-size fudge factor.

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: pgsql-committers(at)postgresql(dot)org
Subject: pgsql: Revert ill-considered change of index-size fudge factor.
Date: 2013-01-11 18:08:26
Message-ID: E1Ttj1m-0001EB-J1@gemulon.postgresql.org
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Revert ill-considered change of index-size fudge factor.

This partially reverts commit 21a39de5809cd3050a37d2554323cc1d0cbeed9d,
restoring the pre-9.2 cost estimates for index usage. That change
introduced much too large a bias against larger indexes, as per reports
from Jeff Janes and others. The whole thing needs a rewrite, which I've
done in HEAD, but the safest thing to do in 9.2 is just to undo this
multiplier change.

Branch
------
REL9_2_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/3e9960e9d935e7e7c12e78441f99befc877563ef

Modified Files
--------------
src/backend/utils/adt/selfuncs.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)

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