Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753620AbWKDTSV (ORCPT ); Sat, 4 Nov 2006 14:18:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753664AbWKDTSV (ORCPT ); Sat, 4 Nov 2006 14:18:21 -0500 Received: from artax.karlin.mff.cuni.cz ([195.113.31.125]:29099 "EHLO artax.karlin.mff.cuni.cz") by vger.kernel.org with ESMTP id S1753619AbWKDTSV (ORCPT ); Sat, 4 Nov 2006 14:18:21 -0500 Date: Sat, 4 Nov 2006 20:18:20 +0100 (CET) From: Mikulas Patocka To: Grzegorz Kulewski Cc: dean gaudet , =?iso-8859-1?Q?J=F6rn?= Engel , linux-kernel@vger.kernel.org Subject: Re: New filesystem for Linux In-Reply-To: Message-ID: References: <20061102235920.GA886@wohnheim.fh-wedel.de> X-Personality-Disorder: Schizoid MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1355 Lines: 35 On Sat, 4 Nov 2006, Grzegorz Kulewski wrote: > On Sat, 4 Nov 2006, Mikulas Patocka wrote: >>> > If it overflows, it increases crash count instead. So really you have > >>> 2^47 >>> > transactions or 65536 crashes and 2^31 transactions between each crash. >>> >>> it seems to me that you only need to be able to represent a range of the >>> most recent 65536 crashes... and could have an online process which goes >>> about "refreshing" old objects to move them forward to the most recent >>> crash state. as long as you know the minimm on-disk crash count you can >>> use it as an offset. >> >> After 65536 crashes you have to run spadfsck --reset-crash-counts. Maybe I >> add that functionality to kernel driver too, so that it will be formally >> corect. > > Is there any reason you can not make these fields 64 or even 128 bits in size > to increase these "limits" dramatically? Yes First --- you need a table of 65536 entries. Table of 4G entries would be too large. Second --- it will make structures larger and thus some operations (like scanning directory with find) slower. Mikulas - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/