On Thu, Mar 10, 2011 at 12:09:08PM -0700, Joseph Hall wrote: > >Question 1: Why is my non-sparse file full of zeros, sitting inside >the filesystem inside the new sparse file, not taking up a lot of >space?
cp creates holes for sparse files from long sequences of 0's. This leads to a handy trick when you are copying a VM disk image. If the VM has been running for a while and writing/unlinking files, you can do: dd if=/dev/zero of=/tmp/foo; rm -f /tmp/foo Then shutdown the VM, copy the disk image with "cp --sparse=always", and your new disk image file should be much smaller. -Peter /* PLUG: http://plug.org, #utah on irc.freenode.net Unsubscribe: http://plug.org/mailman/options/plug Don't fear the penguin. */
