Received: from localhost (unknown [200.46.204.183]) by mail.postgresql.org (Postfix) with ESMTP id 060806324DB for ; Fri, 27 Feb 2009 20:17:06 -0400 (AST) Received: from mail.postgresql.org ([200.46.204.86]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 92345-05 for ; Fri, 27 Feb 2009 20:17:02 -0400 (AST) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from yw-out-2324.google.com (yw-out-2324.google.com [74.125.46.30]) by mail.postgresql.org (Postfix) with ESMTP id BAD2763477E for ; Fri, 27 Feb 2009 20:17:02 -0400 (AST) Received: by yw-out-2324.google.com with SMTP id 5so940723ywh.73 for ; Fri, 27 Feb 2009 16:17:01 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:cc:content-type :content-transfer-encoding; bh=gSWkltgoEXpfNZSX+xJnMt9p9/PYfowzNJbh6DjY4GE=; b=XaGNuaQEQsd32maBTn/zz1koOjWUXK9nVfG2YI4K95U2LC7zeS6juTMNBxLFl5yt5P QnrGsnKUB5IUGXOXTlGMXq76SpF/AJMcxq/NpDerJ14pIgV/AjmJFblZ7BsEOhnX9Wj/ RKImfc7zjG3K6FBQP7hoMdbtCFPrycizCMQ1Y= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=mShk8BYMIdMG9vwiZqDf8mDzT0XjJe2w9RVw5sygBiNj7BZGwwdtDv/RhCEkUVkCqD GMdxPtQHvM9l0FCDiQoszMJM+ih9fetoy+ux9Z6wK6UoLXuEsTG2ivHmUi53YxtU6BJO uxiq72SIM8QQwxMwYrsjfa3UzwvaVmr7kfNIw= MIME-Version: 1.0 Received: by 10.151.148.2 with SMTP id a2mr4947723ybo.37.1235780220972; Fri, 27 Feb 2009 16:17:00 -0800 (PST) In-Reply-To: <93739F94E0F3BA43AD72423E2482341AE064C0@sw-rz010.gsf.de> References: <93739F94E0F3BA43AD72423E2482341AE064B7@sw-rz010.gsf.de> <93739F94E0F3BA43AD72423E2482341AE064C0@sw-rz010.gsf.de> Date: Fri, 27 Feb 2009 17:17:00 -0700 Message-ID: Subject: Re: Question to transaction ID wraparound From: Scott Marlowe To: "Lentes, Bernd" Cc: pgsql-admin@postgresql.org Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=0 tagged_above=0 required=5 tests=none X-Spam-Level: X-Archive-Number: 200902/264 X-Sequence-Number: 31485 On Fri, Feb 27, 2009 at 4:42 AM, Lentes, Bernd wrote: > > > Scott Marlowe wrote: >> -----Urspr=FCngliche Nachricht----- >> Von: Scott Marlowe [mailto:scott.marlowe@gmail.com] >> Gesendet: Freitag, 27. Februar 2009 11:04 >> An: Lentes, Bernd >> Cc: pgsql-admin@postgresql.org >> Betreff: Re: [ADMIN] Question to transaction ID wraparound >> >> On Wed, Feb 25, 2009 at 3:05 AM, Lentes, Bernd >> wrote: >> > Hello ML, >> > >> > I'm very new to Postgres. >> > In the log, i got messages concerning transaction ID wraparound. >> > I red the documentation and made a vaccum on that database. >> > In the documentation i also found the hint to look in the database >> > with "SELECT datname, age(datfrozenxid) FROM pg_database;", >> which i did. >> > I did the command several times in a few seconds, and this >> number is >> > growing very quickly, although i'm not expecting >> transactions in the database. >> >> Please note that nearly EVERYTHING that happens in postgres >> is a transaction. =A0if you type a single command, boom, it's a >> transaction. >> You actually get fewer transaction events if you enclose a >> bunch of stuff in begin; commit; pairs than if you run single >> commands. >> > Scott, why does the number increase ? > If it says how many transactions are still possible, the number should de= crease, not increase. What I wrote was about the number you saw from the log entries. That tells you how many transactions you have left before wraparound would happen. Read up on what the age() stuff means here: http://www.postgresql.org/docs/8.3/static/routine-vacuuming.html