From owner-freebsd-performance@FreeBSD.ORG Wed Mar 12 00:25:57 2008 Return-Path: Delivered-To: freebsd-performance@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 20F86106566C; Wed, 12 Mar 2008 00:25:57 +0000 (UTC) (envelope-from markir@paradise.net.nz) Received: from smtp4.clear.net.nz (smtp4.clear.net.nz [203.97.37.64]) by mx1.freebsd.org (Postfix) with ESMTP id E149E8FC20; Wed, 12 Mar 2008 00:25:56 +0000 (UTC) (envelope-from markir@paradise.net.nz) Received: from zmori.markir.net (121-73-161-240.dsl.telstraclear.net [121.73.161.240]) by smtp4.clear.net.nz (CLEAR Net Mail) with ESMTP id <0JXL00ESHCHOZM00@smtp4.clear.net.nz>; Wed, 12 Mar 2008 13:10:38 +1300 (NZDT) Date: Wed, 12 Mar 2008 13:10:23 +1300 From: Mark Kirkwood In-reply-to: To: Ivan Voras Message-id: <47D71F6F.2090600@paradise.net.nz> MIME-version: 1.0 Content-type: text/plain; charset=UTF-8; format=flowed Content-transfer-encoding: 7bit References: <571396.91912.qm@web50512.mail.re2.yahoo.com> User-Agent: Thunderbird 2.0.0.9 (X11/20071203) Cc: freebsd-performance@freebsd.org Subject: Re: pgbench results X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 12 Mar 2008 00:25:57 -0000 Ivan Voras wrote: > > The thing is - I *do* have a similar setup here: HP DL370 G5, 2x4-core > 1.86 GHz, 4 GB RAM, 6 drives in RAID10, 512 MB cache (can pull > 200 > MB/s off the array), with all settings like in the posted link except > shared_buffer=1900 MB, and I "only" get this: > > tps = 2834.026175 (including connections establishing) > tps = 2839.080739 (excluding connections establishing) > > This is still far bellow ~~ 4500 trans/s from the link and I wonder if > my results are within what I should be getting. The benchmark in the > link above was done with faster CPUs (but I'm not CPU bound - at least > 30% idle), but with 3 times the memory and I'm guessing more memory > would help here, but I'm not sure. > > What's strange is that toggling synchronous_commit doesn't have a > significant effect on performance (it does increase CPU idle time). With > synchronous_commit=off, I get: > > tps = 2886.980477 (including connections establishing) > tps = 2891.776081 (excluding connections establishing) > > The article refers to a controller with a battery backed write cache - that could easily explain the difference if you do not have one (he's paying nothing for fsync wheres you are). regards Mark