X-Original-To: pgsql-sql-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id B7B238B9CE6 for ; Thu, 3 Feb 2005 15:15:41 +0000 (GMT) Received: from svr1.postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 39272-02 for ; Thu, 3 Feb 2005 15:15:35 +0000 (GMT) Received: from anchor-post-34.mail.demon.net (anchor-post-34.mail.demon.net [194.217.242.92]) by svr1.postgresql.org (Postfix) with ESMTP id BA5298B9BD0 for ; Thu, 3 Feb 2005 15:15:38 +0000 (GMT) Received: from mwynhau.demon.co.uk ([193.237.186.96] helo=mainbox.archonet.com) by anchor-post-34.mail.demon.net with esmtp (Exim 4.42) id 1Cwihh-0000Ox-EK; Thu, 03 Feb 2005 15:15:37 +0000 Received: from [192.168.1.17] (client17.archonet.com [192.168.1.17]) by mainbox.archonet.com (Postfix) with ESMTP id 43D9F15D01; Thu, 3 Feb 2005 15:15:32 +0000 (GMT) Message-ID: <42024014.2030901@archonet.com> Date: Thu, 03 Feb 2005 15:15:32 +0000 From: Richard Huxton User-Agent: Mozilla Thunderbird 1.0 (X11/20041206) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Din Adrian Cc: pgsql-sql@postgresql.org Subject: Re: [PERFORM] Tunning postgresql on linux (fedora core 3) References: <420202D0.7070602@archonet.com> <42022DA2.3040000@archonet.com> <42023A94.5040904@archonet.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.068 tagged_above=0 required=5 tests=AWL, FORGED_RCVD_HELO X-Spam-Level: X-Archive-Number: 200502/64 X-Sequence-Number: 20175 Din Adrian wrote: > sorry about cc ... > this is the site: > http://www.varlena.com/varlena/GeneralBits/Tidbits/annotated_conf_e.html > but I gues is not right ... hmm It's not that it's incorrect, just that you should always use the manuals as a starting point. > On Thu, 03 Feb 2005 14:52:04 +0000, Richard Huxton > wrote: > >> I'll repeat myself: >> >> >> >> >> Please CC the mailing list as well as replying to me, so that others >> can help too. >> >> >> >> >> Din Adrian wrote: >> >>> On Thu, 03 Feb 2005 13:56:50 +0000, Richard Huxton >>> wrote: >>> >>>> Please CC the mailing list as well as replying to me, so that >>>> others can help too. >>>> >>>> >>>>> b) in docs say that after 7.2 seting this to false does'n turn >>>>> off the wall ...!? wich option does? >>>> >>>> >>>> >>>> The docs don't say that, as far as I can see. It doesn't make sense >>>> to turn off the WAL. >>> >>> hmm this is the doc about ... >>> ' NOTE: Since 7.2, turning fsync off does NOT stop WAL. It does >>> stop checkpointing, however. This is a change in the notes that >>> follow Turn WAL off (fsync=false) only for a read-only database or >>> one where the database can be regenerated from external software. >>> While RAID plus UPSes can do a lot to protect your data, turning >>> off fsync means that you will be restoring from backup in the event >>> of hardware or power failure.' >> >> >> I don't know what this is, and you don't give a URL, but it DOES NOT >> appear to be in the manuals. >> >> You should probably read the sections of the manuals regarding >> "run-time configuration" and "write ahead logs". The manuals are >> quite extensive, are available online at http://www.postgresql.org/ >> and also in most distributions. >> >> This is probably a good place to start. >> http://www.postgresql.org/docs/8.0/interactive/runtime-config.html#RUNTIME-CONFIG-WAL >> >> >>> If you turn it off you should have more speed ... !!!??? >> >> >> Basically, as I said in my last email - fsync=true makes sure >> transaction details are safely stored on disk. If you turn this off, >> the database doesn't have to wait for the data to physically be >> written to the disk. But, if power fails then data might be in OS or >> disk cache and so lost when you restart the machine. >> >> Please CC the mailing list if you reply to this message. >> -- >> Richard Huxton >> Archonet Ltd >> > > > -- Richard Huxton Archonet Ltd