[BBLISA] Backing up sparse files ... VM's and TrueCrypt ... etc

[Edward Ned Harvey]

> Could you accomplish what you want with xdelta? I've been interested
> in something like this for versioning whole disk images used with VMs
> and AMIs. Example follows which shows that xdelta is pretty speedy at
> least in my simplified 1 GB sparse file test. For the cost of some
> very small delta files I assume I could restore the image to any
> version. Shouldn't be too much work to script something around this.

I'll have to look into this.  Never heard of xdelta before.  Based on what
you wrote, the one thing that seems like it might be a problem, at first
glance is ...
It appears xdelta reads two files on disk and diff's them, right?  So you
couldn't generate the delta in less than 2x the time required to read your
sparse file once, right?  I am planning to consult the man pages etc ...
haven't done it yet ...