X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (av.hub.org [200.46.204.144]) by postgresql.org (Postfix) with ESMTP id 6062211F621B for ; Tue, 18 Apr 2006 06:02:30 -0300 (ADT) X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Score: 0.106 X-Spam-Level: X-Spam-Status: No, score=0.106 required=5 tests=[AWL=0.106] Received: from postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id pvpqbVOzNkeP for ; Tue, 18 Apr 2006 06:02:24 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey- Received: from mail.logix-tt.com (unknown [212.211.145.186]) by postgresql.org (Postfix) with ESMTP id B0DD211F61BC for ; Tue, 18 Apr 2006 06:02:26 -0300 (ADT) Received: from kingfisher.intern.logix-tt.com (Tba08.t.pppool.de [89.55.186.8]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.logix-tt.com (Postfix) with ESMTP id 7A7C9656CD; Tue, 18 Apr 2006 11:03:21 +0200 (CEST) Received: from [127.0.0.1] (localhost [127.0.0.1]) by kingfisher.intern.logix-tt.com (Postfix) with ESMTP id 91B64181C1F3F; Tue, 18 Apr 2006 11:02:37 +0200 (CEST) Message-ID: <4444AB2A.5080607@logix-tt.com> Date: Tue, 18 Apr 2006 11:02:34 +0200 From: Markus Schaber Organization: Logical Tracking and Tracing International AG, Switzerland User-Agent: Debian Thunderbird 1.0.7 (X11/20051017) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Francisco Reyes Cc: Pgsql performance Subject: Re: Inserts optimization? References: <200604141400.38982.mcousin@sigma.fr> In-Reply-To: X-Enigmail-Version: 0.93.0.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Archive-Number: 200604/366 X-Sequence-Number: 18450 Hi, Francisco, Francisco Reyes wrote: > I only wonder what is safer.. using a second or two in commit_delay or > using fsync = off.. Anyone cares to comment? It might be that you misunderstood commit_delay. It will not only delay the disk write, but also block your connnection until the write actually is performed. It will rise the throughput in multi-client scenarios, but will also rise the latency, and it will absolutely bring no speedup in single-client scenarios. It does not decrease safety (in opposite to fsync=off), data will be consistent, and any application that has successfully finished a commit can be shure their data is on the platters.[1] HTH, Markus [1] As long as the platters don't lie, but that's another subject. -- Markus Schaber | Logical Tracking&Tracing International AG Dipl. Inf. | Software Development GIS Fight against software patents in EU! www.ffii.org www.nosoftwarepatents.org