[RFC PATCH v2 0/4] Add support for LZ4-compressed kernel

[Russell King - ARM Linux]

On Wed, Feb 27, 2013 at 04:36:47PM +0900, Kyungsik Lee wrote:
> Compiler: Linaro ARM gcc 4.6.2
> 2. ARMv7, 1.7GHz based board
>    Kernel: linux 3.7
>    Uncompressed Kernel Size: 14MB
>          Compressed Size  Decompression Speed
>     LZO  6.0MB            34.1MB/s            Old
>          ----------------------------------------
>          6.0MB            34.7MB/s            New
>          6.0MB            52.2MB/s(UA)
>     =============================================
>     LZ4  6.5MB            86.7MB/s
> UA: Unaligned memory Access support

That is pretty conclusive - it shows an 8% increase in image size vs a
66% increase in decompression speed.  It will take a _lot_ to offset
that increase in decompression speed.

So, what I think is that yes, we should accept LZ4 and drop LZO from
the kernel - the "fast but may not be small" compression title has
clearly been taken by LZ4.

Akpm - what's your thoughts?