delta rpms - can we turn them off

[John Reiser]

> Doesn't the current process assume that xz always produces the same
> output?

Yes, the deltarpm process depends on xz giving the same output
when run by the consumer of the .drpm as when run by the producer.
If not, then deltarpm gives a warning and ignores the .drpm --
the entire new .rpm must be downloaded.

> 
> What would happen if a newer version of xz/lzma comes out which (for
> example) produces better compressed output while still remaining
> compatible with the file format and older decompression tools?

Then there would be a "one-time" event where none of the .drpm
could be used, until xz on the consumer machine matches (catches up to)
xz on the producer machine.