Re: performance drop on 8.2.4, reverting to 8.1.4 - Mailing list pgsql-performance

From Steinar H. Gunderson
Subject Re: performance drop on 8.2.4, reverting to 8.1.4
Date
Msg-id 20070518094921.GA13598@uio.no
Whole thread Raw
In response to performance drop on 8.2.4, reverting to 8.1.4  ("Liviu Ionescu" <ilgb@livius.net>)
Responses Re: performance drop on 8.2.4, reverting to 8.1.4
List pgsql-performance
On Fri, May 18, 2007 at 12:02:44PM +0300, Liviu Ionescu wrote:
> the 8.2.4 plan with join_collapse_limit = 1 (with default it was worse, full of nested loops)

It will probably be useful with EXPLAIN ANALYZE of your queries, not just the
EXPLAIN.

> "Nested Loop Left Join  (cost=32.01..2012.31 rows=1 width=230)"

It looks like the planner thinks this is going to be really cheap -- so it's
misestimating something somewhere. Have you ANALYZEd recently?

/* Steinar */
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