Re: [OE-core] [PATCH 3/9] mtd-utils: disable LZO by default

[richard.purdie@linuxfoundation.org]

On Wed, 2022-05-25 at 10:34 +0000, Ross Burton wrote:
> > This and kernel compression are the two pieces that worry me a
> > little.
> > LZO is still probably one of the best speed/size compromises and
> > was
> > the reason it was added to jffs2. I'm not sure there are many
> > devices
> > that still use flash directly via jffs2 but this probably still
> > does
> > have a use there. Obviously it would still be in meta-oe but I'm
> > worried the "off by default" will catch out a few old BSPs and be a
> > pain to enable. At lot of this history was paged out in long term
> > storage!
> 
> Enabling should just be a matter of pulling in meta-oe and flipping
> the packageconfigs, so I don’t see this as a huge problem.

My worry is that it changes the task checksums for the native tools and
means the BSP can never be YP Compat.

> Looking in the time machine that is meta-handheld, I see the zaurus
> machines turn on LZO in the JFFS2 kernel module, but they also build
> UBIFS images which explicitly use zlib instead of lzo.  UBIFS also
> support Zstd now, so that’s probably a better option all around: it
> compresses almost as well as zlib but almost as fast as lzo[1].

If the zaurus moved to ubifs, there is probably less of an issue and
just the kernel boot time remains but I'd hope zstd is being used there
too now (or will be).

Cheers,

Richard