From mboxrd@z Thu Jan 1 00:00:00 1970 From: Al Viro Subject: Re: Question regarding to store file system metadata in database Date: Sun, 19 Mar 2006 19:47:23 +0000 Message-ID: <20060319194723.GA27946@ftp.linux.org.uk> References: <4ae3c140603182048k55d06d87ufc0b9f0548574090@mail.gmail.com> <441CE71E.5090503@gmail.com> <4ae3c140603190948s4fcd135er370a15003a0143a8@mail.gmail.com> <1142791121.31358.21.camel@localhost.localdomain> <4ae3c140603191011r7b68f4aale01238202656d122@mail.gmail.com> <1142792787.31358.28.camel@localhost.localdomain> <4ae3c140603191050k3bf7e960q9b35fe098e2fbe35@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: mingz@ele.uri.edu, mikado4vn@gmail.com, linux-kernel , linux-fsdevel@vger.kernel.org Return-path: Received: from zeniv.linux.org.uk ([195.92.253.2]:11155 "EHLO ZenIV.linux.org.uk") by vger.kernel.org with ESMTP id S1750790AbWCSTr0 (ORCPT ); Sun, 19 Mar 2006 14:47:26 -0500 To: Xin Zhao Content-Disposition: inline In-Reply-To: <4ae3c140603191050k3bf7e960q9b35fe098e2fbe35@mail.gmail.com> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Sun, Mar 19, 2006 at 01:50:22PM -0500, Xin Zhao wrote: > Last, database-based file system is not so complex. As first step, I > am just proposing to store pathanem-to-inode number in database. So it > is basically a simple table. We don't really need any fancy features > provided by db system. That's why I said a reduced db system is > enough. So the only difference betwen db-based file system and a > regular one is that regular file system use directory file to store > entries, but db-based file system use database to achieve the same > goal. Looks like db will be a more efficient way. ;-) Define "database". And explain how any of existing filesystems manages to _not_ qualify your definition. As for "more efficient"... 300 lookups per second is less than an improvement. It's orders of magnitude worse than e.g. ext2; I don't know in which world that would be considered more efficient, but I certainly glad that I don't live there.