From owner-freebsd-fs@FreeBSD.ORG Mon Feb 25 17:34:05 2013 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.FreeBSD.org [8.8.178.115]) by hub.freebsd.org (Postfix) with ESMTP id 4CD5A9D1 for ; Mon, 25 Feb 2013 17:34:05 +0000 (UTC) (envelope-from daniel@digsys.bg) Received: from smtp-sofia.digsys.bg (smtp-sofia.digsys.bg [193.68.3.230]) by mx1.freebsd.org (Postfix) with ESMTP id BA86DA6C for ; Mon, 25 Feb 2013 17:34:04 +0000 (UTC) Received: from dcave.digsys.bg (dcave.digsys.bg [192.92.129.5]) (authenticated bits=0) by smtp-sofia.digsys.bg (8.14.5/8.14.5) with ESMTP id r1PHXsbF029070 (version=TLSv1/SSLv3 cipher=DHE-RSA-CAMELLIA256-SHA bits=256 verify=NO) for ; Mon, 25 Feb 2013 19:33:54 +0200 (EET) (envelope-from daniel@digsys.bg) Message-ID: <512BA082.3070605@digsys.bg> Date: Mon, 25 Feb 2013 19:33:54 +0200 From: Daniel Kalchev User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:10.0.12) Gecko/20130125 Thunderbird/10.0.12 MIME-Version: 1.0 To: freebsd-fs@freebsd.org Subject: Re: Improving ZFS performance for large directories References: <19DB8F4A-6788-44F6-9A2C-E01DEA01BED9@dragondata.com> <20130201192416.GA76461@server.rulingia.com> <19E0C908-79F1-43F8-899C-6B60F998D4A5@dragondata.com> <5124AC69.6010709@FreeBSD.org> <237DCD81-5CAB-466B-8BF4-543D195FA545@dragondata.com> In-Reply-To: <237DCD81-5CAB-466B-8BF4-543D195FA545@dragondata.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 25 Feb 2013 17:34:05 -0000 On 25.02.13 19:00, Kevin Day wrote: > I've been hesitating to increase the arc size because we've only got 64GB of memory here and I can't add any further. The processes running on the system themselves need a fair chunk of ram, so I'm trying to figure out how we can either upgrade this motherboard to something newer or reduce our memory size. I've got a feeling I'm going to need to do this, but since this is a non-commercial project it's kinda hard to spend that much money on it. :) Just make vfs.zfs.arc_meta_limit as big as arc_max. This is safe. By default it is 25% of arc_max I believe. In your case, you are better caching more metadata than file data anyway. Daniel