[Yum-devel] Integrating drpm support

[Zdenek Pavlas]

Hi,

The native drpm support is complete enough to be used and tested.
I'm quite satisfied with the performance, but the applydeltarpm
backend needs more work.  I'm going to make a rawhide release
today.

- download of .drpm and .rpm files now may run in parallel.

- with --downloadonly, both drpm downloads and delta rebuilds
  run without holding the yum lock.

- code is much simpler (less than 200 LOCs, from 679 in plugin).
  changing the DL process from 2-pass to (mostly) 1-pass seems
  to be a win.  Deltainfo parsing is much faster and uses less
  memory.  Some local file checksumming was saved, too.

The biggest con ATM is that applydeltarpm runs from DL checkfunc
callback, and is not parallelized.  It does, however, overlap
with package downloads but does not use multiple cores.