A more efficient up2date service using binary diffs

[Kyrre Ness Sjobak]

man, 14.03.2005 kl. 20.25 skrev Paul A. Houle:
> 	I was thinking about this stuff four years ago when I couldn't get DSL at  
> home and it was absolutely painful to update RH 7 (or was it 8?) with  
> up2date.
> 
> 	The most obscene case was that up2date made me download 20 megs of font  
> files to fix a a bad configuration file.
> 
> 	If we were designing this kind of system as if users mattered,  it might  
> make more sense to make it files-centric rather than rpm-centric.  I  
> really hate the idea of making the system count on having rpms available,   
> because I'm not so good about keeping the original disks around.  (Plus  
> the survival of optical disks is hit-or-miss.  I've had some disks that  
> lasted 8 years after getting treated with moderate care,  and I've had  
> other ones that I couldn't read after walking them across campus.)
> 
> 	It seems just as feasable to send diffs of the ~files~ rather than diffs  
> of the ~rpms~;  if we're going to go through the bother of implementing  
> something like this,  it makes sense to make something that "just works"  
> rather than another one of these things that almost works (or rather,   
> works if you have the disks,  works if you are ready to pull the disks out  
> if you have yum,  kinda might work if you have a network install,  maybe  
> it won't work.)
> 
>        This should be thought of as an optimization.  If the files on the  
> disk don't checksum match the rpm database,  we ought to download and  
> install the new rpm.
> 
> ----
> 
> 	I've always wondered if the Red Hat Network would have been more  
> profitable if it had been less wasteful of bandwidth.

Files: think scripts that are run when the rpm is installed...

_I_ think we should let rpm be rpm, and rather focus about how to *get*
the new rpm's to the users, not how we can hack up rpm itself to do some
weird half-baked thing.

Harddisk are cheap those days, compared to internet, if you are on a
dial-up. So i guess most dialup users will be satisfyed with an option
to copy all the base rpm's to the harddrive, even if it migth be a waste
of disk space. Those on broadband migth chose to save themselves some
diskspace, and rather download more (exactly like they do today).

When i was on dialup (untill christmas this year), i used to first
download the rpm's to my laptop at scool, carry them home on its
harddrive (never underestimate the bandwith of a bus with a laptop
rolling down a small road!), copy them over to /var/cache/{apt|yum}, and
update. It worked. Kindof. But some kind of prpm would be better.

Kyrre