[EROS-Arch] Package handling...

[Karp, Alan]

The debate seems to be around finding the best time to delete an old version
of a component that may be used by several applications.  Why delete the old
versions at all?  The trend is the opposite, namely keep everything.  I'm
currently using backup software that runs in the background and saves a copy
to the server everytime I close a file.  The estimate is that 2,000 users at
HP Labs will produce far less than 1 TB per year with this approach.

Disks are getting bigger faster than we can fill them, at least with code
and text.  Since the days of Plan 9, studies have shown that disks are
getting emptier, not fuller.  Every time you upgrade your disk, you do it
for less money and at a time when you are farther from capacity.

If you never delete an old version of a component, you  don't need reference
counts.  You also don't have to worry that some application you only run
once every few years will fail because of an incompatibility.  The cost will
be a few percent of your disk space, and that percentage will decrease over
time.

_________________________
Alan Karp
Principal Scientist
Decision Technology Department
Hewlett-Packard Laboratories MS 1U-2
1501 Page Mill Road
Palo Alto, CA 94304
(650) 857-3967, fax (650) 857-6278
https://ecardfile.com/id/Alan_Karp
http://www.hpl.hp.com/personal/Alan_Karp/