[Yum-devel] yum on an olpc machine (slooooooooooow)

[Michael Stenner]

On Sun, Dec 17, 2006 at 09:59:58PM -0500, seth vidal wrote:
> we store the checksum of the old db (compressed and uncompressed) as
> well as the new db file in repomd.xml
> 
> yum would download repomd.xml - if the checksum of its sqlite db files
> is the same as the old checksum, then it downloads the sqlite
> transaction diff b/c it can use it. when it doesn't match then grab the
> whole file.
> 
> does that make sense to everyone?

This seems safe, meaning that it shouldn't lead to corruption or
ambiguity.  Whether it provides practical improvement depends upon
usage patterns.  In the limit that yum is run much more frequently
than the repo changes, then a full download should be rare.  Do we
know that to be the case?  If it's not, then keeping multiple diffs is
always possible, although I think we all agree that the concept gets
ugly fast and that should be avoided unless it provides a substantial
benefit.
					-Michael
-- 
  Michael D. Stenner                            mstenner at ece.arizona.edu
  ECE Department and Optical Sciences Center                520-626-1619
  University of Arizona                                         ECE 524G