From owner-freebsd-fs@FreeBSD.ORG Thu Mar 11 13:00:15 2010 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id AD0CB10656AE; Thu, 11 Mar 2010 13:00:15 +0000 (UTC) (envelope-from md@scoutsengidsenvlaanderen.be) Received: from scoutsengidsenvlaanderen.be (mail.scoutsengidsenvlaanderen.be [81.83.17.184]) by mx1.freebsd.org (Postfix) with ESMTP id 9AB3F8FC2E; Thu, 11 Mar 2010 13:00:13 +0000 (UTC) Received: from [192.168.1.163] (account md [192.168.1.163] verified) by scoutsengidsenvlaanderen.be (CommuniGate Pro SMTP 5.3.3) with ESMTPA id 34078327; Thu, 11 Mar 2010 14:00:11 +0100 Message-ID: <4B98E95B.90806@scoutsengidsenvlaanderen.be> Date: Thu, 11 Mar 2010 14:00:11 +0100 From: Michiel Detailleur User-Agent: Thunderbird 2.0.0.23 (Windows/20090812) MIME-Version: 1.0 To: Pawel Jakub Dawidek References: <4B97A963.9040300@scoutsengidsenvlaanderen.be> <20100310174411.GE1715@garage.freebsd.pl> In-Reply-To: <20100310174411.GE1715@garage.freebsd.pl> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-fs@freebsd.org Subject: Re: [Spam? ] Re: ZFS snapshot name length limit? (File name too long) X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 11 Mar 2010 13:00:15 -0000 Pawel Jakub Dawidek wrote: > On Wed, Mar 10, 2010 at 03:14:59PM +0100, Michiel Detailleur wrote: > >> This seems to imply a maximum length of 72 characters (snapshot '@' sign >> excluded) for *usable* snapshots? (usable in the sense that we can >> mount/look into them) >> >> What limit am I (we?) hitting here? Is this a problem with ZFS itself or >> with FreeBSD? Sure looks like a silly limit for the filesystem that >> touts 'biggest everything'. >> > > From looking at the code, I think you hitting this limit: > > This is FreeBSD limit caused by statfs structure: > > /* > * filesystem statistics > */ > [...] > #define MNAMELEN 88 /* size of on/from name bufs */ > [...] > > ZFS mounts snapshots on lookup and this is this mount that fails. > So all that would need to be done to allow mounting snapshots with longer names would be to increase this value? (I'm not a C programmer, so bear with me :) ) Is that something you could commit a change for as the ZFS committer? Or is there more to it than that? In any case: thanks for your answer and for all your hard work in getting ZFS in FreeBSD! :) Michiel