Re: inserting into brand new database faster than old database

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: "Missner, T(dot) R(dot)" <T(dot)R(dot)Missner(at)Level3(dot)com>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: inserting into brand new database faster than old database
Date: 2004-07-10 02:52:04
Message-ID: 2000.1089427924@sss.pgh.pa.us
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"Missner, T. R." <T(dot)R(dot)Missner(at)Level3(dot)com> writes:
> ... Each day a brand new set of tables is
> created and eventually the old tables are dropped.

You did not say which PG version you are using (tut tut) but my first
thought is that it's a pre-7.4 release and your problems trace to bloat
in the system-catalog indexes. The indexes on pg_class and pg_attribute
would be quite likely to suffer serious bloat if you continually create
and drop tables, because the range of useful table OIDs will be
continually shifting. We didn't fix this until 7.4.

If you are seeing this in 7.4.* then more investigation is needed...

regards, tom lane

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