ext2/3/4 group size

[Yioryos Asprobounitis]

--- On Thu, 3/31/11, Arnd Bergmann <arnd at arndb.de> wrote:

> From: Arnd Bergmann <arnd at arndb.de>
> Subject: Re: ext2/3/4 group size
> To: devel at lists.laptop.org
> Cc: "Yioryos Asprobounitis" <mavrothal at yahoo.com>
> Date: Thursday, March 31, 2011, 3:34 AM
> On Thursday 31 March 2011 08:45:24
> Yioryos Asprobounitis wrote:
> > 
> > I was wondering if it makes any sense when making an
> ext fs on an SDcard 
> > to try to align the erase block of the card with the
> ext2 group size. 
> > eg assuming a card with a 4KB pages and 4MB erase
> blocks, try something
> > like `mkfs.ext3 -b 4096 -g 1024'

...and a last one on this.
apparently you can not have 1024 groop blocks in ext2/3

$ mkfs.ext3 -b 4096 -g 1024 /dev/mmcblk0p1 
mke2fs 1.41.12 (17-May-2010)
/dev/mmcblk0p1: Cannot create filesystem with requested number of inodes while setting up superblock