From: Tom Lane <tgl@sss.pgh.pa.us>
To: Jean-David Beyer <jeandavid8@verizon.net>
Cc: pgsql performance <pgsql-performance@postgresql.org>
Subject: Re: Curious about dead rows.
Date: Sat, 10 Nov 2007 12:08:11 -0500
Message-ID: <16627.1194714491@sss.pgh.pa.us> (raw)
In-Reply-To: <4735DBDB.5050208@verizon.net>
References: <4735DBDB.5050208@verizon.net>
Jean-David Beyer <jeandavid8@verizon.net> writes:
> I am doing lots of INSERTs on a table that starts out empty (I did a
> TRUNCATE on it). I am not, AFAIK, doing DELETEs or UPDATEs. Autovacuum is
> on. I moved logging up to debug2 level to see what was going on, and I get
> things like this:
> "vl_as": scanned 3000 of 5296 pages, containing 232944 live rows and 1033
> dead rows; 3000 rows in sample, 411224 estimated total rows
> A little later, it says:
> "vl_as": scanned 3000 of 6916 pages, containing 233507 live rows and 493
> dead rows; 3000 rows in sample, 538311 estimated total rows
Well, *something* is doing deletes or updates in that table. Better
look a bit harder at your application ...
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, jeandavid8@verizon.net
Subject: Re: Curious about dead rows.
In-Reply-To: <16627.1194714491@sss.pgh.pa.us>
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