XO-1 to switch back to JFFS2

[Daniel Drake]

Hi,

I'm planning on moving the XO-1 back to JFFS2 for 12.1.0 - and likely
for the future too.

The reasons being:

1. UBIFS is considerably less space-efficient than JFFS2.

http://www.linux-mtd.infradead.org/faq/ubifs.html#L_jffs2_space

We needed the disk space already, and we're battling constant growth
of the Fedora platform. Deployments will also appreciate not losing
50mb of space which can be used for content, user data, etc.


2. UBIFS is less robust in the face of bad blocks.

At image creation time, UBIFS allocates a number of blocks that are
used when other blocks go bad. When that allocation is exceeded (i.e.
when blocks go bad), UBI goes read-only and there is no simple
recovery except another reflash.
JFFS2 is more robust here.


The ubifs_image module will remain in olpc-os-builder for those who
wish to try it, but the OLPC configs and images will switch back to
JFFS2 (which is what we've used in all stable releases til now).

Comments/objections?

Thanks,
Daniel