From owner-freebsd-questions@freebsd.org Thu Feb 18 20:30:28 2016 Return-Path: Delivered-To: freebsd-questions@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id B661EAAC5DF for ; Thu, 18 Feb 2016 20:30:28 +0000 (UTC) (envelope-from paul@ifdnrg.com) Received: from smtp.thepharmacycentre.com (pharmacycentre.ifdnrg.com [193.200.98.77]) by mx1.freebsd.org (Postfix) with ESMTP id 62B783B7 for ; Thu, 18 Feb 2016 20:30:26 +0000 (UTC) (envelope-from paul@ifdnrg.com) Received: from [192.168.0.100] (cpc14-sgyl28-2-0-cust626.18-2.cable.virginm.net [82.39.86.115]) (authenticated bits=0) by smtp.thepharmacycentre.com (8.15.2/8.14.9) with ESMTPSA id u1IKHgop066609 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NO) for ; Thu, 18 Feb 2016 20:17:43 GMT (envelope-from paul@ifdnrg.com) X-Authentication-Warning: smtp.thepharmacycentre.com: Host cpc14-sgyl28-2-0-cust626.18-2.cable.virginm.net [82.39.86.115] claimed to be [192.168.0.100] To: freebsd-questions@freebsd.org From: Paul Macdonald Subject: ZFS + dovecot Message-ID: <56C62724.60201@ifdnrg.com> Date: Thu, 18 Feb 2016 20:18:44 +0000 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 18 Feb 2016 20:30:28 -0000 Hi, I'm starting to see reduced performance on a 2 disk SATA server with a mirrored 2TB pool running dovecot. -Concurrent logged in users are ~ 1000. -lucene plugin for indexing minimal CPU and RAM usage (8GB, but will be increasing to 16GB for ZFS), only hit swap once in 2 years ( recently) a few processes showing of zio->i under top. I'm about to add a 460GB SSD as an L2ARC cache and hoping but note entirely sure that will help given that most people want to see new mail fast. Does anyone have any performance tips for this workload? TIA Paul. -- ------------------------- Paul Macdonald IFDNRG Ltd Web and video hosting ------------------------- t: 0131 5548070 m: 07970339546 e: paul@ifdnrg.com w: http://www.ifdnrg.com ------------------------- IFDNRG 40 Maritime Street Edinburgh EH6 6SA ---------------------------------------------------- High Specification Dedicated Servers from £100.00pm ----------------------------------------------------