From owner-freebsd-fs@FreeBSD.ORG  Thu Aug 28 23:13:05 2003
Return-Path: <owner-freebsd-fs@FreeBSD.ORG>
Delivered-To: freebsd-fs@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP
	id E3AF016A4BF; Thu, 28 Aug 2003 23:13:05 -0700 (PDT)
Received: from mailman.zeta.org.au (mailman.zeta.org.au [203.26.10.16])
	by mx1.FreeBSD.org (Postfix) with ESMTP
	id AE21843FBF; Thu, 28 Aug 2003 23:13:03 -0700 (PDT)
	(envelope-from bde@zeta.org.au)
Received: from gamplex.bde.org (katana.zip.com.au [61.8.7.246])
	by mailman.zeta.org.au (8.9.3p2/8.8.7) with ESMTP id QAA04036;
	Fri, 29 Aug 2003 16:12:54 +1000
Date: Fri, 29 Aug 2003 16:12:53 +1000 (EST)
From: Bruce Evans <bde@zeta.org.au>
X-X-Sender: bde@gamplex.bde.org
To: Sean Chittenden <seanc@freebsd.org>
In-Reply-To: <20030828171955.GE83759@perrin.nxad.com>
Message-ID: <20030829160907.L2783@gamplex.bde.org>
References: <3F4D5957.8000204@potentialtech.com>
	<Pine.NEB.3.96L.1030827225030.29532F-100000@fledge.watson.org>
	<20030828171955.GE83759@perrin.nxad.com>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
cc: freebsd-database@freebsd.org
cc: freebsd-fs@freebsd.org
cc: freebsd-performance@freebsd.org
cc: Robert Watson <rwatson@freebsd.org>
cc: Bill Moran <wmoran@potentialtech.com>
Subject: Re: Some additional tests run on my performance testing
X-BeenThere: freebsd-fs@freebsd.org
X-Mailman-Version: 2.1.1
Precedence: list
List-Id: Filesystems <freebsd-fs.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-fs>,
	<mailto:freebsd-fs-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-fs>
List-Post: <mailto:freebsd-fs@freebsd.org>
List-Help: <mailto:freebsd-fs-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-fs>,
	<mailto:freebsd-fs-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Fri, 29 Aug 2003 06:13:06 -0000

On Thu, 28 Aug 2003, Sean Chittenden wrote:

> For the sake of eating my own advice and in an attempt to verify the
> numbers you suggest above, I loaded a DB with 8k and 16K blocks
> (translation: almost all write activities).
>
> With 8K blocks:
> 15.188u 3.404s 7:12.27 4.2%     209+340k 1251+0io 0pf+0w
> 14.867u 3.686s 7:32.54 4.0%     201+327k 1252+0io 0pf+0w
>
> avg wall clock sec to complete: 442
>
> With 16K blocks:
> 15.192u 3.312s 6:44.43 4.5%     198+322k 1253+0io 0pf+0w
> 15.120u 3.330s 6:51.43 4.4%     205+334k 1254+0io 0pf+0w
>
> avg wall clock sec to complete: 407
>
> Which is different than what your results suggest, but I'll take the
> 35sec/8% speedup any day of the week and twice on Sunday.  Granted

How much faster is it with smaller block sizes (same or smaller block
size for the filesystem in all cases)?  Large block sizes are unlikely
to be more efficient if they are much larger than the average transaction
size.

Bruce