Received: from localhost (unknown [200.46.204.187]) by postgresql.org (Postfix) with ESMTP id 6F59E9F9B1E for ; Sat, 8 Sep 2007 18:06:06 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.187]) (amavisd-maia, port 10024) with ESMTP id 31962-06 for ; Sat, 8 Sep 2007 18:05:56 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.5 Received: from nabagan.bluegap.ch (nabagan.bluegap.ch [88.198.58.248]) by postgresql.org (Postfix) with ESMTP id 0DA3E9F9B15 for ; Sat, 8 Sep 2007 18:05:59 -0300 (ADT) Received: from [192.168.77.28] (p54BD86AD.dip0.t-ipconnect.de [::ffff:84.189.134.173]) (AUTH: CRAM-MD5 markus@bluegap.ch) by nabagan.bluegap.ch with esmtp; Sat, 08 Sep 2007 23:47:18 +0200 id 0040A950.46E31866.00001DC7 Message-ID: <46E30EB4.7020304@bluegap.ch> Date: Sat, 08 Sep 2007 23:05:56 +0200 From: Markus Schiltknecht User-Agent: Icedove 1.5.0.12 (X11/20070607) MIME-Version: 1.0 To: Tom Lane CC: pgsql-hackers@postgreSQL.org Subject: Re: WIP patch for latestCompletedXid method of computing snapshot xmax References: <3018.1189214811@sss.pgh.pa.us> <28198.1189282917@sss.pgh.pa.us> In-Reply-To: <28198.1189282917@sss.pgh.pa.us> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200709/363 X-Sequence-Number: 107515 Hello Tom, Tom Lane wrote: > So on the strength of that, I'm going to go ahead and commit the patch, > but I'd be interested to see benchmarks from people with access to > better hardware. I've just completed two dbt2 test runs on a mid-level system, with 4GB RAM and a 7 disk SATA RAID 1+0 w/ BBU. Once with code as of 2007/09/05 18:00 (which is *before* the first lazy xid commit) and once with cvs HEAD (2007/09/08 +latestCompletedXid.patch. Here are the results from the first test run (test run 33, without lazy xid): > $ cat 33/driver/results.out > Response Time (s) > Transaction % Average : 90th % Total Rollbacks % > ------------ ----- --------------------- ----------- --------------- ----- > Delivery 3.97 3.745 : 7.844 11844 0 0.00 > New Order 45.35 3.844 : 7.692 135192 1352 1.01 > Order Status 3.95 2.728 : 6.371 11764 0 0.00 > Payment 42.74 2.649 : 6.349 127415 0 0.00 > Stock Level 4.00 2.172 : 5.634 11915 0 0.00 > ------------ ----- --------------------- ----------- --------------- ----- > > 1103.45 new-order transactions per minute (NOTPM) > 120.1 minute duration > 0 total unknown errors > 1003 second(s) ramping up And that's with HEAD +latestCompletedXid.patch (test run 34): > $ cat 34/driver/results.out > Response Time (s) > Transaction % Average : 90th % Total Rollbacks % > ------------ ----- --------------------- ----------- --------------- ----- > Delivery 3.96 3.843 : 8.223 11760 0 0.00 > New Order 45.28 4.049 : 8.451 134398 1300 0.98 > Order Status 3.97 2.877 : 6.815 11777 0 0.00 > Payment 42.80 2.745 : 6.718 127027 0 0.00 > Stock Level 4.00 2.280 : 6.129 11859 0 0.00 > ------------ ----- --------------------- ----------- --------------- ----- > > 1097.71 new-order transactions per minute (NOTPM) > 120.1 minute duration > 0 total unknown errors > 1003 second(s) ramping up Both tests ran for two hours, had 100 warehouses and 50 connections. shared_buffers were set to 1024MB, effective_cachesize = 3800MB, all other settings were standard. Regards Markus