Re: [PATCH] INITRAMFS: Add option to preserve mtime from INITRAMFScpio images
From: nyet
Date: Thu Sep 04 2008 - 03:13:39 EST
Frans Meulenbroeks wrote:
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.
An earlier rev patch made it optional. I can resubmit of course.
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