Re: [PATCH] x86/boot: Support uncompressed kernel

[Yinghai Lu]

On Thu, Mar 23, 2017 at 5:51 AM, Chao Peng <chao.p.peng@xxxxxxxxxxxxxxx> wrote:
> Compressed kernel has its own drawback: uncompressing takes time. Even
> though the time is short enough to ignore for most cases but for cases that
> time is critical this is still a big number. In our on-going optimization
> for kernel boot time, the measured overall kernel boot time is ~90ms while
> the uncompressing takes ~50ms with gzip.
>
> The patch adds a 'CONFIG_KERNEL_RAW' configure choice so the built binary
> can have no uncompressing at all. The experiment shows:
>
>     kernel               kernel size    time in decompress_kernel
>     compressed (gzip)    3.3M           53ms
>     uncompressed         14M            3ms

How about the time difference for bootloader to read kernel from
flash/disk/network to ram?

Thanks

Yinghai