From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.nokia.com ([131.228.20.172] helo=mgw-ext13.nokia.com) by canuck.infradead.org with esmtps (Exim 4.63 #1 (Red Hat Linux)) id 1ITDOV-0002wg-Qu for linux-mtd@lists.infradead.org; Thu, 06 Sep 2007 05:11:27 -0400 Subject: Re: General performance of NAND operations i.e mount and ls From: Artem Bityutskiy To: Konstantin Kletschke In-Reply-To: <20070906084418.GC2164@z1.synertronixx> References: <20070906081215.GA5693@anita.doom> <1189067241.14370.23.camel@sauron> <20070906084418.GC2164@z1.synertronixx> Content-Type: text/plain; charset=utf-8 Date: Thu, 06 Sep 2007 12:11:04 +0300 Message-Id: <1189069864.14370.34.camel@sauron> Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Cc: linux-mtd@lists.infradead.org Reply-To: dedekind@infradead.org List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, 2007-09-06 at 10:44 +0200, Konstantin Kletschke wrote: > > Well, JFFS2 scans on mount, so no wonder it is that long. Summary shoul= d > > improves the situation - do you have it enabled? >=20 > Summary is enabled in Kernel but I created the files with flash_eraseall > and mounted the block device as jffs2 and copied the files onto it in > system. So no summaryze, is that right? Yup, summaries are there then. > > I do not think you may make JFFS2 work faster on such big flash with > > such big files, at least it will be difficult and would require core > > jffs2 changes. >=20 > Okay, I wanted to check if the time is okay for 520MHz core with 104MHz > Bus and 8Bit flash. If this is the case my Hardware driver is okay. > There is no urge to improve this stat() time and fragtree building at > the moment. If it takes so long and the driver is okay it wioll take so > long (arguing with boss and customers :-)). Try to measure raw R/W, e.g with dd. But beware dd will fail at the first met bad block. Something like: Read: dd if=3D/dev/mtd4 of=3D/dev/null bs=3D4096 count=3D512 Write: dd if=3D/dev/zero of=3D/dev/mtd4 bs=3D4096 count=3D512 It'll print raw R/W speed. But beware dd will fail at the first bad block, so yo may have to play with count=3D or skip=3D for read and seek=3D for write to find a large enough contiguous area without bad blocks. --=20 Best regards, Artem Bityutskiy (=D0=91=D0=B8=D1=82=D1=8E=D1=86=D0=BA=D0=B8=D0=B9 =D0=90= =D1=80=D1=82=D1=91=D0=BC)