Received: from localhost (unknown [200.46.204.183]) by postgresql.org (Postfix) with ESMTP id 13EEA64FD32 for ; Tue, 28 Oct 2008 13:03:15 -0300 (ADT) Received: from postgresql.org ([200.46.204.86]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 03269-10 for ; Tue, 28 Oct 2008 13:03:11 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from outmail129149.authsmtp.com (outmail129149.authsmtp.com [62.13.129.149]) by postgresql.org (Postfix) with ESMTP id 9C2D664FD2A for ; Tue, 28 Oct 2008 13:03:11 -0300 (ADT) Received: from mail-c189.authsmtp.com (mail-c189.authsmtp.com [62.13.128.71]) by punt10.authsmtp.com (8.14.2/8.14.2/Kp) with ESMTP id m9SG2cwr099743; Tue, 28 Oct 2008 16:02:38 GMT Received: from [192.168.0.3] (85-211-99-122.dyn.gotadsl.co.uk [85.211.99.122]) (authenticated bits=0) by mail.authsmtp.com (8.14.2/8.14.2/Kp) with ESMTP id m9SG2X88047040; Tue, 28 Oct 2008 16:02:36 GMT Subject: Re: Updating FSM on recovery From: Simon Riggs To: Heikki Linnakangas Cc: PostgreSQL-development In-Reply-To: <1225208150.3971.191.camel@ebony.2ndQuadrant> References: <49072021.7010801@enterprisedb.com> <1225208150.3971.191.camel@ebony.2ndQuadrant> Content-Type: text/plain Date: Tue, 28 Oct 2008 16:02:31 +0000 Message-Id: <1225209751.3971.196.camel@ebony.2ndQuadrant> Mime-Version: 1.0 X-Mailer: Evolution 2.12.0 Content-Transfer-Encoding: 7bit X-Server-Quench: d7577485-a509-11dd-bc7a-001f29070be2 X-AuthRoute: OCdxZQATClZOTQEd DAteCiNZVAwpPBRK HVkIKg5MJUcNSQVJ NksadBtFag1bYlpF HGQLW1xEUVt7WWF/ aA0fZQBDYEtPQQxj TklLQE1QEQdtHhxP Wxd9JRsafw1GfHlw YUYsX3JeVAouckN6 RUpcEHBXYGdpdWEe BBRFJVBTIR5Kfh4T aFl/U3NfNGdJBC9q VzwTFhsSEA9kHWxo Wg0EMVMUTg4lJRt0 QBZKBzgkGlMIXTRb X-Authentic-SMTP: 61633235383639.kestrel.dmpriest.net.uk:1378/Kp X-Report-SPAM: If SPAM / abuse - report it at: http://www.authsmtp.com/abuse X-Virus-Status: No virus detected - but ensure you scan with your own anti-virus system! 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: 200810/1416 X-Sequence-Number: 126433 On Tue, 2008-10-28 at 15:35 +0000, Simon Riggs wrote: > I wonder if there is merit in having an XLogInsertMulti() which inserts > multiple records in a batch as a way of reducing WALInsertLock traffic. > It might be possible to piggyback FSM records onto the main heap > changes. Or possibly an XLogInsertDeferred() which just queues up some work so the next time we call XLogInsert() it will insert the deferred work as well as the main work all in one lock cycle. It would only be usable for low priority info like FSM stuff that isn't needed for recovery. Maybe we could do that with hints also. -- Simon Riggs www.2ndQuadrant.com PostgreSQL Training, Services and Support