[Buildroot] Why can't I see any effects by different rootfs compression methods ??

[Arnout Vandecappelle]

On 06/02/14 10:19, Frank Ihle wrote:
> Hi,
> 
> I'm using Buildroot to generate a uImage with a kernel, which in the end
> starts busybox. I tried the different compression modes (kernel
> compression, built-in initramfs compression and the rootfs compression).
> The first 2 options worked quiet well but when it comes to apply
> different compression methodes (e.g. LZMA, bzip2) on  rootfs in make
> menuconfig nothing changes, neither size nor decompress time.
> 
> Why is it like that ? And how can I extract files of the generated
> uImage, so that i can see what really has been compressed ?

 The rootfs compression only affects the rootfs image that is generated
in output/images, not the initramfs that is linked into the kernel. The
latter is purely controlled by kernel options (which you did).

 Note that built-in initramfs compression is pointless, because it will
be compressed again with the kernel compression method - and that usually
increases the size rather than decreasing it.


 Regards,
 Arnout


-- 
Arnout Vandecappelle                          arnout at mind be
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