From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jamie Lokier Date: Sun, 20 Apr 2008 18:29:37 +0100 Subject: [U-Boot-Users] ubi and u-boot In-Reply-To: <1208709853.6654.23.camel@vader.jdub.homelinux.org> References: <4808AE6F.4030505@largestprime.net> <1208536808.6654.6.camel@vader.jdub.homelinux.org> <20080418165957.GG31520@shareable.org> <1208546341.6654.8.camel@vader.jdub.homelinux.org> <20080420160413.GC14268@shareable.org> <1208709853.6654.23.camel@vader.jdub.homelinux.org> Message-ID: <20080420172937.GA16184@shareable.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Josh Boyer wrote: > > Hamish Moffatt wrote (Message-ID: <20080407073227.GA6317@cloud.net.au>): > > > Sorry I should've said 512MiB perhaps: 512 megabytes. > > > UBI attach time appears to be about 6 seconds. > > > > If 6 seconds is as fast as it can be done, annoying but fair enough. > > You should read that thread a bit more carefully. The scan time is > highly dependent upon the NAND driver beneath UBI. For example, a UBI > scan/attach on a 1GiB device on OLPC was 2 seconds. Ah, I intended to quote the 2 seconds too but forgot, sorry. I think 2 seconds per gigabyte is a significant time, too, but not so much. The followup suggested it was due to the speed of the chip, not so much the driver. > > Adding _another_ 6 seconds to the boot time seems a lot to me. > > You mean adding another "X amount of time depending on factors outside > of UBI's control." Well, yes, that would be a reason to consider whether doing it is a good idea :-) > > I can understand the hesitation, but I think 6 seconds just to find > > the kernel - especially when doing a 'disk resume' - is quite a lot. > > You should really stop quoting this 6 second number. Let's call it 2 seconds per gigabyte, then. > > Note that I haven't tried UBI myself yet. I'm going on what has been > > written to the list so far, as quoted above. > > Maybe you should try it :). I will when good looking figures are being quoted on the list ;-) -- Jamie