[CentOS-virt] compress raw image
cpolish at surewest.net
Tue Aug 9 19:19:35 EDT 2011
Rainer Traut wrote:
> Am 08.08.2011 18:51, schrieb Momo:
> > Hi
> > No, he's talking filling with zeros unused blocks. That's a prerequisite
> > to optimize for a sparse image _on the other side_ and/or compression
> > during the transfer.
> > I know of an ext2/3/4 utility that does precisely that. I have no idea
> > if such an utility exists for NTFS.
> > It exists for NTFS, have a look at "sdelete.exe" with -c option.
> Sorry for getting back so late.
> Yes, guys, exactly what I meant was filling unused space with zeros.
> The linux tools to compress and transfer cannot read the ntfs data
> structure and compress every garbage. But if unused blocks are filled
> with zeros one can achieve much better compression.
> I looked into sdelete.exe, this really is helpful but obviously works in
> running instance.
> My idea is to mount the raw image with ntfs3g and create a big file with
> zeros. This should be sufficient, like Marco said.
Don't forget rsync's parms --bwlimit=0 --compress-level=1
More information about the CentOS-virt