From owner-freebsd-performance@FreeBSD.ORG Fri Dec 28 21:40:50 2007 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 D728A16A468 for ; Fri, 28 Dec 2007 21:40:50 +0000 (UTC) (envelope-from bright@elvis.mu.org) Received: from elvis.mu.org (elvis.mu.org [192.203.228.196]) by mx1.freebsd.org (Postfix) with ESMTP id C7F0F13C4E8 for ; Fri, 28 Dec 2007 21:40:50 +0000 (UTC) (envelope-from bright@elvis.mu.org) Received: by elvis.mu.org (Postfix, from userid 1192) id BF9371A4D80; Fri, 28 Dec 2007 13:38:51 -0800 (PST) Date: Fri, 28 Dec 2007 13:38:51 -0800 From: Alfred Perlstein To: Alexandre Biancalana Message-ID: <20071228213851.GE76698@elvis.mu.org> References: <8e10486b0712191109n3d21b02cyf5183ee0cd01d8ce@mail.gmail.com> <20071221201625.GZ16982@elvis.mu.org> <8e10486b0712211249v4c5571ddud21b277f686992b2@mail.gmail.com> <20071221212808.GE16982@elvis.mu.org> <8e10486b0712211555n3efe8729qff14387be128cf10@mail.gmail.com> <20071222002535.GL16982@elvis.mu.org> <8e10486b0712251647uddf80f9sa6cacb42dfa94ff5@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8e10486b0712251647uddf80f9sa6cacb42dfa94ff5@mail.gmail.com> User-Agent: Mutt/1.4.2.3i Cc: freebsd-performance@freebsd.org Subject: Re: Bad performance when accessing a lot of small files 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: Fri, 28 Dec 2007 21:40:50 -0000 * Alexandre Biancalana [071225 16:45] wrote: > On 12/21/07, Alfred Perlstein wrote: > > > Have you tried the 'noatime' mount option? That should help. > > Yeah, the zfs set atime=off was already done.... > > > > > Can you provide a histogram of the count of files per directory? > > Excuse-me, but I don't understand.... Distribution of files per directory, example: 1000 files in 9 dirs 1001 files in 12 dirs find /path_to_root/ -type f | sed 's/\/[^/]*$//' | uniq -c | \ awk '{print $1}' | sort -n | uniq -c That will print out the number of files per dir. 2 98 3 102 1 103 2 105 Or something like that. -- - Alfred Perlstein