Received: from localhost (unknown [200.46.204.183]) by mail.postgresql.org (Postfix) with ESMTP id 3F666632D40 for ; Tue, 21 Apr 2009 08:49:03 -0300 (ADT) 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 57772-02 for ; Tue, 21 Apr 2009 08:48:53 -0300 (ADT) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from qw-out-2122.google.com (qw-out-2122.google.com [74.125.92.24]) by mail.postgresql.org (Postfix) with ESMTP id 8D9F263238F for ; Tue, 21 Apr 2009 08:48:53 -0300 (ADT) Received: by qw-out-2122.google.com with SMTP id 8so1065245qwh.61 for ; Tue, 21 Apr 2009 04:48:52 -0700 (PDT) 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=M8Q1PzB3wm9aYR6qJeszwYXwTE8anMRgdJFU7LX7bfc=; b=U7ZeNcUAcvnqDMIfwfDgqDJGub17HO96FGv8ma2QqOERlRu/JUIV2sU2UifBFs6Esz fZeOcP6yro76pHCBdS6xG5ypm1z2vZp8+xVMRf9MPn6/nnFPEitAyTAtWA4om4eBf3OE So/3GDYAhRG8P18rxAaMJrkj/w4Shkn2ZJ5Vc= 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=rLpNyaSK1qmgZtx72sK0WzMSGS5c9ybrf/9eGCJjKksVY9mNdlbwpvAiKtQHaXizl2 yem6pum/uFYJFIk4Y92IyfsCPNt4tZDcJKHu/W8ohEXyc7rcEOE5Jkpnzjy4H058fkA+ /J0Vz80e+kuymVVzElnwwjVwrCM3ItNNLpIqc= MIME-Version: 1.0 Received: by 10.220.98.202 with SMTP id r10mr8263189vcn.67.1240314532114; Tue, 21 Apr 2009 04:48:52 -0700 (PDT) In-Reply-To: <49EDADD6.1090006@enterprisedb.com> References: <3f0b79eb0903242329j12865d55s348f5c873a956e71@mail.gmail.com> <3f0b79eb0904132241p18084914g792cb8e5ab3eebb3@mail.gmail.com> <3f0b79eb0904150101pb1c59a3ubb422867e8e6a944@mail.gmail.com> <49EC3B01.6050509@enterprisedb.com> <3f0b79eb0904200354u41b54017u16dc73d021c03cdb@mail.gmail.com> <49EC8B06.3020204@enterprisedb.com> <1240311836.23905.206.camel@ebony.fara.com> <49EDAB5B.5040400@enterprisedb.com> <1240313150.23905.222.camel@ebony.fara.com> <49EDADD6.1090006@enterprisedb.com> Date: Tue, 21 Apr 2009 20:48:51 +0900 Message-ID: <3f0b79eb0904210448l36d9bb27u8b832540010a6f20@mail.gmail.com> Subject: Re: New trigger option of pg_standby From: Fujii Masao To: Heikki Linnakangas Cc: Simon Riggs , Guillaume Smet , Tom Lane , Peter Eisentraut , Kevin Grittner , pgsql-hackers Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit 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: 200904/1070 X-Sequence-Number: 137173 Hi, On Tue, Apr 21, 2009 at 8:28 PM, Heikki Linnakangas wrote: > Simon Riggs wrote: >> >> If you do this, then you would have to change the procedure written into >> the 8.3 docs also. Docs aren't backpatchable. >> >> What you propose is *better* than raw pg_standby is now, but still not >> enough in all cases, as I think you know. > > No, I don't. What is the case where it doesn't work? It's the case which I described as the 2nd comment to your proposal. 1. pg_standby tries to restore a non-existent file 1-1. remove the trigger file 1-2. pg_standby exits with non-zero code 2. the startup process tries to read it from pg_xlog 2-1. it is applied 3. the startup process tries to restore the next file using pg_standby 3-1. pg_standby gets *stuck* since the requested file and trigger file don't exist. Regards, -- Fujii Masao NIPPON TELEGRAPH AND TELEPHONE CORPORATION NTT Open Source Software Center