Re: [PATCH] INITRAMFS: Add option to preserve mtime from INITRAMFS cpio images

[Frans Meulenbroeks]

2008/9/4 Nye Liu <nyet@xxxxxxx>:
> On Wed, Sep 03, 2008 at 03:22:31PM -0700, Andrew Morton wrote:
>> > From: Nye Liu <nyet@xxxxxxxx>
>> >
>> > When unpacking the cpio into the initramfs, mtimes are not preserved by
>> > default. This patch adds an INITRAMFS_PRESERVE_MTIME option that allows mtimes
>> > stored in the cpio image to be used when constructing the initramfs. For
>> > embedded applications that run exclusively out of the initramfs, this is
>> > invaluable.
>>
>> Why is it "invlauable".  Please explain this value in full detail -
>> it's the whole reason for merging the patch!
>
> When building embedded application initramfs images, its nice to know
> when the files were actually created during the build process - that
> makes it easier to see what files were modified when so we can compare
> the files that are being used on the image with the files used during
> the build process. This might help (for example) to determine if the
> target system has all the updated files you expect to see w/o having to
> check MD5s etc.

Hm.

"Invaluable" != "nice to know".

What worries me is that this code is executed at boot time (when
populating the ramfs).
For embedded systems a fast boot time is often important.
I admit that the net effect of this on boot time is marginal (but some
might consider having mtime a marginal benefit), and 100 cents also
make a dollar, so my suggestion would be to either reject this patch
or make it optional (e.g. depending on some debug config flag).

Best regards, Frans.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/