From owner-freebsd-stable@freebsd.org Tue Nov 24 14:30:36 2015 Return-Path: Delivered-To: freebsd-stable@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 C94C2A36353 for ; Tue, 24 Nov 2015 14:30:36 +0000 (UTC) (envelope-from mike@sentex.net) Received: from smarthost1.sentex.ca (smarthost1.sentex.ca [IPv6:2607:f3e0:0:1::12]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (Client CN "smarthost.sentex.ca", Issuer "smarthost.sentex.ca" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 8B4941A71 for ; Tue, 24 Nov 2015 14:30:36 +0000 (UTC) (envelope-from mike@sentex.net) Received: from [IPv6:2607:f3e0:0:4:f025:8813:7603:7e4a] (saphire3.sentex.ca [IPv6:2607:f3e0:0:4:f025:8813:7603:7e4a]) by smarthost1.sentex.ca (8.15.2/8.15.2) with ESMTP id tAOEUYBq029422; Tue, 24 Nov 2015 09:30:34 -0500 (EST) (envelope-from mike@sentex.net) Subject: Re: ZFS - poor performance with "large" directories To: Albert Cervin , freebsd-stable@freebsd.org References: From: Mike Tancsa Organization: Sentex Communications Message-ID: <5654747B.10902@sentex.net> Date: Tue, 24 Nov 2015 09:30:19 -0500 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.3.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.75 X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 24 Nov 2015 14:30:36 -0000 On 11/24/2015 9:00 AM, Albert Cervin wrote: > However, we are seeing en exponential decrease in performance to write to > the file server when the number of files in the directory grows (when it > goes up to ~6000 files it becomes unusable and the write time has gone from > a fraction of a second to ten seconds). Have you tried adjusting vfs.zfs.arc_meta_limit to a higher value ? Do you have any memory pressures on your server ? Have a look at this thread https://lists.freebsd.org/pipermail/freebsd-fs/2013-February/016492.html ---Mike -- ------------------- Mike Tancsa, tel +1 519 651 3400 Sentex Communications, mike@sentex.net Providing Internet services since 1994 www.sentex.net Cambridge, Ontario Canada http://www.tancsa.com/