🚀 go-pugleaf

In article <1993Jan25.121021.1787@macc.wisc.edu> anderson@macc.wisc.edu (Jess  
Anderson) writes:
> In article <SCOTT.93Jan24203511@nic.gac.edu>
> scott@nic.gac.edu (Scott Hess) writes:
> >In my experience, zip (or gzip) would reduce the disk needs
> >by up to %40, which is a pretty substantial improvement.  Furthermore,
> >compression is free and works even if new disk space is purchased,
> >so investment in a reasonable compression scheme is going to keep
> >paying back in the future.
> 
> Unquestionably better compression technologies are a wise
> investment.  They pay back not only for the servers, but for
> the user community as well, because most of us are anything
> but swimming in extra disk space.
>
> There are significant labor costs in this dimension too.
> F'rinstance, were I to update my MS-DOS archive, which is
> stored on 800 floppy disks, from ARC to ZIP, I'd be looking
> at the time it takes to do this on a 12 MHz AT clone,
> feeding the disks one at a time.  [...]

Another benefit of compression, not mentioned yet, is that it
could reap benefits _immediately_.  Even if the schools can accept
the gift of disk space, it may take quite a while for whatever
process needs to be gone through to complete, plus additional time
to install/setup the new drive.

Also, Jess's example, while I can sympathize with it, having once
converted a mere 50 full floppies to a new compression scheme, is
perhaps somewhat misleading.  Floppies need constant attention to
feed them, as he notes, but the hard drive does not.  A script
could easily be set up to travel through the archive, replacing
compressed files with their gzip'd counterparts.

An informal test that I ran earlier today indicates that a wholesale
conversion of the archives from compress to gzip may immediately
generate 80-110 MB of free space on the disk, taking perhaps one
CPU-day (a questionable unit of work, I admit).  Some of the data:
sonata.cc> du 1.0-release		; no compression
26488   1.0-release/source
30004   1.0-release/binaries
4835    1.0-release/demos
61330   1.0-release
sonata.cc> du 1.0-release		; compress (current)
9366    1.0-release/source
16388   1.0-release/binaries
2580    1.0-release/demos
28337   1.0-release
sonata.cc> du 1.0-release		; gzip -9
6373    1.0-release/source
12069   1.0-release/binaries
1978    1.0-release/demos
20423   1.0-release
[I chose the 1.0-release directory as a representative sample of
source and binary files.  Obviously, some other types of files, tiffs
for instance, will compress more or less than any "average" implied
here.]

Of course, actually getting someone to do this will probably being
like getting someone to pull their own tooth...

I don't mean to say that people should stop sending pledges to Jess. As
noted before, simple re-compression is a solution with a finite lifetime.

Christopher Kane
kane@sonata.cc.purdue.edu