From mboxrd@z Thu Jan 1 00:00:00 1970 From: Artem Bityutskiy Subject: Re: New fast(?)-boot results on ARM Date: Sat, 15 Aug 2009 09:14:48 +0300 Message-ID: <4A865258.5090903@gmail.com> References: <20090814170228.GM13320@pengutronix.de> <1158166a0908141304y70300ab3p899b0d4609efded9@mail.gmail.com> Mime-Version: 1.0 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1158166a0908141304y70300ab3p899b0d4609efded9@mail.gmail.com> Sender: linux-embedded-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="utf-8"; format="flowed" To: Denys Vlasenko Cc: Robert Schwebel , linux-kernel@vger.kernel.org, linux-embedded@vger.kernel.org, Arjan van de Ven , Tim Bird , kernel@pengutronix.de On 08/14/2009 11:04 PM, Denys Vlasenko wrote: >> [ 2.742628]< 0.016050> 0x000000360000-0x000004000000 : "root" >> [ 3.058610]< 0.315982> UBI: attaching mtd7 to ubi0 >> [ 3.062878]< 0.004268> UBI: physical eraseblock size: 16384 b= ytes (16 KiB) >> [ 3.070601]< 0.007723> UBI: logical eraseblock size: 15360 b= ytes >> [ 3.070665]< 0.000064> UBI: smallest flash I/O unit: 512 >> [ 3.078564]< 0.007899> UBI: VID header offset: 512 (al= igned 512) >> [ 3.078609]< 0.000045> UBI: data offset: 1024 >> [ 5.006609]< 1.928000> UBI: attached mtd7 to ubi0 >> [ 5.013157]< 0.006548> UBI: MTD device name: "root" > > As others commented, ubi looks slow and you probably need to find out= why. Right. UBI is rather slow in attaching MTD devices. Everything is expla= ined here: http://www.linux-mtd.infradead.org/doc/ubi.html#L_scalability http://www.linux-mtd.infradead.org/doc/ubifs.html#L_scalability There is not very much you can do to speed it up but implement UBI2. UB= IFS would stay intact. There were discussions about this and it does not se= em to be impossibly difficult to do UBI2. Here are few ideas: http://www.linux-mtd.infradead.org/faq/ubi.html#L_attach_faster --=20 Best Regards, Artem Bityutskiy (=D0=90=D1=80=D1=82=D1=91=D0=BC =D0=91=D0=B8=D1=82=D1=8E= =D1=86=D0=BA=D0=B8=D0=B9)