From owner-freebsd-current@FreeBSD.ORG Sun Aug 21 03:27:27 2011 Return-Path: Delivered-To: current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id EB1D9106566B for ; Sun, 21 Aug 2011 03:27:27 +0000 (UTC) (envelope-from kaduk@mit.edu) Received: from dmz-mailsec-scanner-4.mit.edu (DMZ-MAILSEC-SCANNER-4.MIT.EDU [18.9.25.15]) by mx1.freebsd.org (Postfix) with ESMTP id 9D3A98FC0C for ; Sun, 21 Aug 2011 03:27:27 +0000 (UTC) X-AuditID: 1209190f-b7b44ae000000a24-1e-4e5076fe356d Received: from mailhub-auth-2.mit.edu ( [18.7.62.36]) by dmz-mailsec-scanner-4.mit.edu (Symantec Messaging Gateway) with SMTP id 79.7B.02596.EF6705E4; Sat, 20 Aug 2011 23:09:51 -0400 (EDT) Received: from outgoing.mit.edu (OUTGOING-AUTH.MIT.EDU [18.7.22.103]) by mailhub-auth-2.mit.edu (8.13.8/8.9.2) with ESMTP id p7L3CORk004212; Sat, 20 Aug 2011 23:12:25 -0400 Received: from multics.mit.edu (MULTICS.MIT.EDU [18.187.1.73]) (authenticated bits=56) (User authenticated as kaduk@ATHENA.MIT.EDU) by outgoing.mit.edu (8.13.6/8.12.4) with ESMTP id p7L3CM7x012531 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT); Sat, 20 Aug 2011 23:12:24 -0400 (EDT) Received: (from kaduk@localhost) by multics.mit.edu (8.12.9.20060308) id p7L3CLwN026684; Sat, 20 Aug 2011 23:12:21 -0400 (EDT) Date: Sat, 20 Aug 2011 23:12:21 -0400 (EDT) From: Benjamin Kaduk To: Rick Macklem In-Reply-To: <1522286016.115315.1313878060040.JavaMail.root@erie.cs.uoguelph.ca> Message-ID: References: <1522286016.115315.1313878060040.JavaMail.root@erie.cs.uoguelph.ca> User-Agent: Alpine 1.10 (GSO 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; format=flowed; charset=US-ASCII X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFvrGIsWRmVeSWpSXmKPExsUixG6novu/LMDPYE6KxYQrP5gsbrWvYra4 PHUpm8XDZdeYHFg8Znyaz+Lxe/NepgCmKC6blNSczLLUIn27BK6M4+sushQ8Za34/+wCWwPj cZYuRk4OCQETicYLzawQtpjEhXvr2boYuTiEBPYxSux61sEO4WxglJi6tIMRwjnAJLF18X0m CKeBUeL+nOfMIP0sAtoSC5YdZgSx2QRUJGa+2cgGYosIqEtsXt0PVsMs4C7xfMJlJhBbWEBB YsLddWA2p0CAxKOzp4Fu4uDgFXCQ+LO7GCQsJOAvMW9nA1irqICOxOr9U8DO5hUQlDg58wkL xEhLiX9rf7FOYBSchSQ1C0lqASPTKkbZlNwq3dzEzJzi1GTd4uTEvLzUIl0TvdzMEr3UlNJN jKDg5ZTk38H47aDSIUYBDkYlHt5fl/z9hFgTy4orcw8xSnIwKYnysgNDX4gvKT+lMiOxOCO+ qDQntfgQowQHs5IIr5MQUI43JbGyKrUoHyYlzcGiJM7buMPBT0ggPbEkNTs1tSC1CCYrw8Gh JMH7C2SoYFFqempFWmZOCUKaiYMTZDgP0PBSkBre4oLE3OLMdIj8KUZFKXHeHyAJAZBERmke XC8subxiFAd6RZh3LUgVDzAxwXW/AhrMBDRYapcPyOCSRISUVAOj+JF3Ef9dLZ5mXlWwMHde 0r6jTvPMtwmlpiYmaokP5avMHd8tb5Cp91x5UPlNuVL54RLnZPlLP8suV51uOquZENJw0b7X nGlv2c8j8/4vvVKaEjdHkvN0+E43Je4PSneFcjj/bdi1OejbzTcXluc8PKWx84rK4ZNsfVu2 f7qS2vO7vWzfiaXvlFiKMxINtZiLihMBrHRJ5QkDAAA= Cc: pjd@freebsd.org, current@freebsd.org Subject: Re: fsid change of ZFS? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 21 Aug 2011 03:27:28 -0000 On Sat, 20 Aug 2011, Rick Macklem wrote: >> Yes, using vfs_getnewfsid() does not solve the issue. >> >> I noticed that Solaris looked up a fixed array vfssw[] exactly for >> the purpose. I think a table like it is a good solution for fixing >> fsid for each file system. >> >> -- Hiroki > If anyone thinks using a fixed table to assign vfc_typenum for known > file system types is a bad idea, please let us know. Fixed table sounds like a good plan. Is there a reason for/against using a hash table for types that are not in the fixed table? The advantage would be that out-of-tree filesystems get a consistent typenum (modulo hash collisions), but there would be more overhead in maintaining the table. -Ben Kaduk