From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [145.253.187.130] (helo=proxy.baslerweb.com) by pentafluge.infradead.org with esmtp (Exim 4.22 #5 (Red Hat Linux)) id 1A9joM-00024z-TN for ; Wed, 15 Oct 2003 12:27:26 +0100 From: Thomas Koeller To: David Woodhouse Date: Wed, 15 Oct 2003 13:30:02 +0200 References: <1065598642.12197.6.camel@famine> <200310151211.29172.thomas.koeller@baslerweb.com> <1066215157.14783.933.camel@hades.cambridge.redhat.com> In-Reply-To: <1066215157.14783.933.camel@hades.cambridge.redhat.com> MIME-Version: 1.0 Content-Disposition: inline Message-Id: <200310151330.02902.thomas.koeller@baslerweb.com> Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit cc: linux-mtd@lists.infradead.org cc: ecos-discuss@sources.redhat.com Subject: Re: [ECOS] Stress testing JFFS2 List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi David, thanks for your quick response. > All correct. But you miss the observation that we also keep a > raw_node_ref around for _obsolete_ nodes, which perhaps we could avoid. > In fact, we do this because the raw_node_ref is in a singly-linked list, > and it's going to be very inefficient to remove obsoleted nodes from > that list when they become obsolete. I do not think this path leads anywhere I want to go. The flash size was chosen to meet the expected storage requirements, which means that at some point the flash will be filled with valid data and consequently there will be few obsoleted nodes. I expect this to be true for most systems. > Omitting the 'totlen' field should be relatively simple if you're not > freeing obsolete refs. Observe that in 99% of cases, it's true that > > ref->totlen == ref_offset(ref->next_phys) - ref_offset(ref) > > Make it 100% and make me believe it, and you can remove totlen from the > structure. > I will consider that. tk -------------------------------------------------- Thomas Koeller, Software Development Basler Vision Technologies An der Strusbek 60-62 22926 Ahrensburg Germany Tel +49 (4102) 463-162 Fax +49 (4102) 463-239 mailto:thomas.koeller@baslerweb.com http://www.baslerweb.com ==============================