SELECT constant; takes 15x longer on 9.0? - Mailing list pgsql-hackers

From Josh Berkus
Subject SELECT constant; takes 15x longer on 9.0?
Date
Msg-id 4BBACAD6.4000008@agliodbs.com
Whole thread Raw
Responses Re: SELECT constant; takes 15x longer on 9.0?  (Takahiro Itagaki <itagaki.takahiro@oss.ntt.co.jp>)
Re: SELECT constant; takes 15x longer on 9.0?  (Merlin Moncure <mmoncure@gmail.com>)
Re: SELECT constant; takes 15x longer on 9.0?  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
Hackers,

Continuing the performance test:

DBD, like a number of monitoring systems, does "pings" on the database
which look like this:

SELECT 'DBD::Pg ping test';

In our test, which does 5801 of these pings during the test, they take
an average of 15x longer to execute on 9.0 as 8.4 ( 0.77ms vs. 0.05ms ).

Any clue why this would be?

--                                  -- Josh Berkus                                    PostgreSQL Experts Inc.
                        http://www.pgexperts.com
 


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