From owner-freebsd-fs@FreeBSD.ORG Thu Apr 17 09:12:34 2014 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id C92DDA0 for ; Thu, 17 Apr 2014 09:12:34 +0000 (UTC) Received: from mail.bytecamp.net (mail.bytecamp.net [212.204.60.9]) by mx1.freebsd.org (Postfix) with ESMTP id 182B510E4 for ; Thu, 17 Apr 2014 09:12:33 +0000 (UTC) Received: (qmail 17495 invoked by uid 89); 17 Apr 2014 11:12:32 +0200 Received: from stella.bytecamp.net (HELO ?212.204.60.37?) (rs%bytecamp.net@212.204.60.37) by mail.bytecamp.net with CAMELLIA256-SHA encrypted SMTP; 17 Apr 2014 11:12:32 +0200 Message-ID: <534F9AFF.6010809@bytecamp.net> Date: Thu, 17 Apr 2014 11:12:31 +0200 From: Robert Schulze Organization: bytecamp GmbH User-Agent: Mozilla/5.0 (X11; Linux i686; rv:17.0) Gecko/20130330 Thunderbird/17.0.5 MIME-Version: 1.0 To: freebsd-fs@freebsd.org Subject: Re: NFS behavior on a ZFS dataset with no quota remaining References: <21327.21004.879860.960260@hergotha.csail.mit.edu> In-Reply-To: <21327.21004.879860.960260@hergotha.csail.mit.edu> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 17 Apr 2014 09:12:34 -0000 Hi, Am 17.04.2014 06:01, schrieb Garrett Wollman: > Recently one of our users managed to constipate one of our NFS servers > in an odd way. They hit the quota on their dataset, and rather than > having all of their writes error out as they should have, the NFS > server instead stopped responding to all requests. this behaviour is present since the beginnings of ZFS in FreeBSD. When a quota limit is reached, local reads are performing very bad or stall completely. The issue in combination with NFS is even more annoying, I've seen that happen quite often. IMHO this is a flaw which can easily be used to DOS any NFS server with quotas set. with kind regards, Robert Schulze -- /7\ bytecamp GmbH Geschwister-Scholl-Str. 10, 14776 Brandenburg a.d. Havel HRB15752, Amtsgericht Potsdam, Geschaeftsfuehrer: Bjoern Barnekow, Frank Rosenbaum, Sirko Zidlewitz tel +49 3381 79637-0 werktags 10-12,13-17 Uhr, fax +49 3381 79637-20 mail rs@bytecamp.net, web http://bytecamp.net/