[Fedora-livecd-list] RFC- improving livecd installer efficiency

[Mark McLoughlin]

Hi,
	I've lost track of the all the details here but ...

On Tue, 2007-07-10 at 06:07 -0500, Douglas McClendon wrote:
> Question:  Does the current livecd installer inefficiently write lots of 0's to 
> the destination drive that it doesn't need to?
> 
> I think it might.  The os.img on the F7 livecd is a 4G sparse file with about 
> 2.3G of data.  Anaconda's livecdcopy backend uses python's os.read/write.  I 
> would guess that that means that 4G of data is getting written, when 
> theoretically only 2.3G needs to.

	... how about something like this:

  http://www.gnome.org/~markmc/code/e2cp.c

	i.e. read the ext3 metadata and copy everything but the  unallocated
blocks.

	(One thing from the above code you don't want to do is the
check_all_zeros() bit - if an allocated block is all zeros, you *do*
want to copy the zeros to the disk)

Cheers,
Mark.