Received: from localhost (unknown [200.46.204.184]) by postgresql.org (Postfix) with ESMTP id 739C52E00DC for ; Fri, 7 Dec 2007 23:50:31 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.184]) (amavisd-maia, port 10024) with ESMTP id 19016-05 for ; Fri, 7 Dec 2007 23:50:08 -0400 (AST) Received: from rv-out-0910.google.com (rv-out-0910.google.com [209.85.198.185]) by postgresql.org (Postfix) with ESMTP id 9A6D22E0042 for ; Fri, 7 Dec 2007 23:50:26 -0400 (AST) Received: by rv-out-0910.google.com with SMTP id l15so1005636rvb for ; Fri, 07 Dec 2007 19:50:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; bh=S+RdN8m+33Wtn0VDPoNPE8B0Ao/oxro10bPs7z6SYBE=; b=G46rhKEPbes0ibxGvxlPgin3QHlLHSajpalSKM/Umhzih2LjUtPzFLk6iy7wSVGf3HWpvlH8PteKQVlo4dPkTedQUlybNm74eX/59QJitlARSfnChosmj16+79aTfPJ+uGNqurmUYtFKcGZmXSnkzBD3mdh/YtkCLVEXCwt5bc0= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=CNvUhn8n1xZTi69ufpTYr4AUbryQHZy5oy4FL+i87DjAvo+YPyed6Re6+uQilkjFeYTmF6Ek8nNhdmTOlDt7jf87RrwA0DgxMjKLmRHyH4z2ckFXFYy2ysxGY71tng4ky9ztXdB1tdj0voygDlDB/40Hxw2xIdTgQdtVCvw9woQ= Received: by 10.142.225.11 with SMTP id x11mr772405wfg.1197085824873; Fri, 07 Dec 2007 19:50:24 -0800 (PST) Received: by 10.143.8.5 with HTTP; Fri, 7 Dec 2007 19:50:24 -0800 (PST) Message-ID: <36e682920712071950x522646edub34cab934aa4396e@mail.gmail.com> Date: Fri, 7 Dec 2007 22:50:24 -0500 From: "Jonah H. Harris" To: "Greg Smith" Subject: Re: [DOCS] "distributed checkpoint" Cc: pgsql-docs@postgresql.org, pgsql-hackers@postgresql.org In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20071206220348.GM8451@alvh.no-ip.org> <5958.1196991889@sss.pgh.pa.us> <20071206191944.1d7926d2@commandprompt.com> <20071207034328.GB18310@fetter.org> <1197051730.4255.603.camel@ebony.site> X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200712/211 X-Sequence-Number: 111500 On Dec 7, 2007 10:25 PM, Greg Smith wrote: > > "Smoothed" makes a lot of sense for me. We used to have a checkpoint > > spike, now we don't. > > To be accurate, there used to be a huge and unavoidable spike, now there's > a control that aims to make it smaller. The problem hasn't completely > gone away yet. Agreed. > "Distributed checkpoints prevent I/O spikes during checkpoints" > > It's good this came up, because that is factually wrong; Agreed. > "Checkpoint writes can be spread over a longer time period to smooth the > I/O spike during each checkpoint" Sounds good to me. > It's got spread, it's got smooth, and if I could have worked "silky" in > there too I would have. :) -- Jonah H. Harris, Sr. Software Architect | phone: 732.331.1324 EnterpriseDB Corporation | fax: 732.331.1301 499 Thornall Street, 2nd Floor | jonah.harris@enterprisedb.com Edison, NJ 08837 | http://www.enterprisedb.com/