X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [64.117.224.130]) by svr1.postgresql.org (Postfix) with ESMTP id 2AB84D1B502 for ; Wed, 24 Sep 2003 18:36:20 +0000 (GMT) Received: from svr1.postgresql.org ([64.117.224.193]) by localhost (neptune.hub.org [64.117.224.130]) (amavisd-new, port 10024) with ESMTP id 86558-07 for ; Wed, 24 Sep 2003 15:35:49 -0300 (ADT) Received: from mailav.tor1.inquent.com (mail.inquent.com [216.208.117.106]) by svr1.postgresql.org (Postfix) with ESMTP id DEB65D1B8DE for ; Wed, 24 Sep 2003 15:35:32 -0300 (ADT) Received: from localhost (localhost [127.0.0.1]) by mailav.tor1.inquent.com (Postfix) with ESMTP id 8379010262; Wed, 24 Sep 2003 14:26:43 -0400 (EDT) Received: from [10.0.2.3] (unknown [10.0.2.3]) by mailav.tor1.inquent.com (Postfix) with ESMTP id 7FC7910261; Wed, 24 Sep 2003 14:26:41 -0400 (EDT) Subject: Re: Performance issue From: Rod Taylor To: peter Cc: Postgresql Performance In-Reply-To: References: Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-Si7MKX4F7hhxyh/3esH9" Message-Id: <1064428549.20881.20.camel@jester> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.4 Date: Wed, 24 Sep 2003 14:35:50 -0400 X-Virus-Scanned: by AMaViS perl-11 X-Virus-Scanned: by amavisd-new at postgresql.org X-Archive-Number: 200309/312 X-Sequence-Number: 3678 --=-Si7MKX4F7hhxyh/3esH9 Content-Type: text/plain Content-Transfer-Encoding: quoted-printable > 20,000 items Takes on average 0.078seconds/room > 385,000 items Takes on average .11seconds/room > 690,000 items takes on average .270seconds/room > 1,028,000 items Takes on average .475seconds/room >=20 > As can be seen the time taken to process each room increases. A commit=20 > occurs when a room has been copied. It probably isn't the insert that is getting slower, but a select.=20 Foreign keys to growing tables will exhibit this behaviour. Since the time is doubling with the number of items, you might want to check for a SELECT working with a sequential scan rather than an index scan. --=-Si7MKX4F7hhxyh/3esH9 Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.3 (FreeBSD) iD8DBQA/ceQF6DETLow6vwwRAoOhAJ4pRrBko8LkR6o5r6XfzKQOCDNjrgCfcTjA zozEcK1q8bp5A5iuX6AYcww= =s9HZ -----END PGP SIGNATURE----- --=-Si7MKX4F7hhxyh/3esH9--