Reducing initramfs size and speed up the generation

[Adrien Nader]

On Tue, Jul 11, 2023, Michael Hudson-Doyle wrote:
> I was wondering if it make sense to construct a zstd dictionary for
> compressing kernel modules but I didn't realize they need to be available
> at decompression time, I'm not sure the kernel would support that.

I've tried to use the zstd --train and I don't think it is appropriate
here, or at least not without significant preparation of datasets. It's
more suited for many many small and similar files. We don't have that
many files and there are only clusters of similarities, not similarities
shared across every file. Moreover, since our files are big (at least
the one that matter for the overall size), they're already contributing
a lot to the live dictionary and the pre-built one has little overall
influence.

-- 
Adrien