From owner-freebsd-fs@freebsd.org Tue May 17 08:42:48 2016 Return-Path: Delivered-To: freebsd-fs@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 1D322B3D426 for ; Tue, 17 May 2016 08:42:48 +0000 (UTC) (envelope-from wjw@digiware.nl) Received: from smtp.digiware.nl (unknown [IPv6:2001:4cb8:90:ffff::3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id DB15418C0 for ; Tue, 17 May 2016 08:42:47 +0000 (UTC) (envelope-from wjw@digiware.nl) Received: from rack1.digiware.nl (unknown [127.0.0.1]) by smtp.digiware.nl (Postfix) with ESMTP id 24D29153402; Tue, 17 May 2016 10:42:45 +0200 (CEST) X-Virus-Scanned: amavisd-new at digiware.nl Received: from smtp.digiware.nl ([127.0.0.1]) by rack1.digiware.nl (rack1.digiware.nl [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id LKXrGJgCqvNe; Tue, 17 May 2016 10:42:44 +0200 (CEST) Received: from [IPv6:2001:4cb8:3:1:8c49:9de7:acf1:6a1f] (unknown [IPv6:2001:4cb8:3:1:8c49:9de7:acf1:6a1f]) by smtp.digiware.nl (Postfix) with ESMTP id 301D415340A; Tue, 17 May 2016 10:42:44 +0200 (CEST) Subject: Re: Bigger MAX_PATH (Was: Re: State of native encryption in ZFS) To: Peter Jeremy References: <5736E7B4.1000409@gmail.com> <57378707.19425.B54772B@s_sourceforge.nedprod.com> <57385356.4525.E728971@s_sourceforge.nedprod.com> <9ead4b28-9711-5e38-483f-ef9eaf0bc583@digiware.nl> <20160516200543.GC42426@server.rulingia.com> Cc: "freebsd-fs@FreeBSD.org" From: Willem Jan Withagen Organization: Digiware Management b.v. Message-ID: Date: Tue, 17 May 2016 10:42:32 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.1.0 MIME-Version: 1.0 In-Reply-To: <20160516200543.GC42426@server.rulingia.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 17 May 2016 08:42:48 -0000 On 16-5-2016 22:05, Peter Jeremy wrote: > On 2016-May-16 15:18:17 +0200, Willem Jan Withagen wrote: >> Trying to port Ceph is also running into the limit in: >> /usr/include/sys/syslimits.h: >> #define NAME_MAX 255 /* max bytes in a file name */ >> >> but I also found: >> /usr/include/stdio.h: >> #define FILENAME_MAX 1024 /* must be <= PATH_MAX */ >> >> So take a pick?? > > There are two distinct limits: The maximum number of characters in a > pathname component (ie the name seen in a directory entry): For UFS, > this is 255 because the length is stored on disk in a uint8_t (I don't > know the limit for ZFS). The other limit is the maximum number of > characters in a pathname - PATH_MAX. This is used to dimension various > buffers but isn't persistent on disk so you should be able to increase > it by changing the relevant #defines and rebuilding everything. Don't remeber if I did such an experiment. Got to talk to the local engineer of dutie here to see if I can get a few more VMs to go compile and blow up. :) Getting the NAME_MAX size per fs is something I'm going to need in the long run for Ceph to make optimal usage of its capabilities. I think that Linux is now at 1024, and the underlaying store for Ceph is going to 4096..... --WjW