From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-bw0-f218.google.com ([209.85.218.218]) by bombadil.infradead.org with esmtp (Exim 4.69 #1 (Red Hat Linux)) id 1NxJ3f-0007qM-N5 for linux-mtd@lists.infradead.org; Thu, 01 Apr 2010 11:59:36 +0000 Received: by bwz10 with SMTP id 10so1464294bwz.2 for ; Thu, 01 Apr 2010 04:59:33 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: References: <6b5362aa1002260458j571852cbl2f2d86130828333a@mail.gmail.com> <1267559131.1883.1.camel@localhost.localdomain> Date: Thu, 1 Apr 2010 13:59:31 +0200 Message-ID: Subject: Re: Release of UBIL: ubi with log From: Corentin Chary To: Brijesh Singh Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Cc: Artem.Bityutskiy@nokia.com, dedekind1@gmail.com, linux-mtd@lists.infradead.org, rohitvdongre@gmail.com, David Woodhouse , Adrian Hunter List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, Apr 1, 2010 at 1:14 PM, Brijesh Singh w= rote: > Hi, > > On Wed, Mar 31, 2010 at 6:27 PM, Corentin Chary > wrote: >> On Tue, Mar 2, 2010 at 8:45 PM, Artem Bityutskiy w= rote: >>> On Fri, 2010-02-26 at 18:28 +0530, Brijesh Singh wrote: >>>> Hi, >>>> =A0It gives me great pleasure in sharing UBIL: ubi with log. =A0We hav= e >>>> added logging functionality to ubi for reducing mount time. >>>> UBIL uses the "same source base of UBI". The logging functionality can >>>> be added or removed at compile time using "make menuconfig option". >>>> >>>> We have seen mount time reduction of 50% in 1GB NAND. We are expecting >>>> even better results for larger flash memories. >>>> >>>> The source code of UBIL can be found in the following git tree: >>>> http://git.infradead.org/users/brijesh/ubi-2.6.git >>>> >>> >>> Sounds interesting! However, I'm out of office till end of March, and >>> won't be able to look closely at this. But hopefully others will try it= . >>> >> >> Hi, >> Didn't took the time =A0to read the code, I'll try to do so soon. >> Could you tell us more about what you did and how it works ? >> Is it similar to yaffs checkpoints ? When are the log written ? > Not sure with yaffs checkpoints. Yaffs works by writting it's internal memory representation on the nand while unmounting, so it seems to be different. > But commit writes only valid log entries. > Log is written when an eba mapping is changed or when ec of peb is change= d. How this affect write performances ? >> What will happen if you try to mount something that used UBIL with a >> kernel without UBIL support ? > It won't work. Could it work by using a separate UBI volume with the right flag ? Are the log per-volume ? --=20 Corentin Chary http://xf.iksaif.net