[TUHS] CMU Mach sources?

[Theodore Ts'o]

On Mon, Jun 24, 2019 at 05:06:30PM -0700, Larry McVoy wrote:
> All interesting points but messy code is messy code.  I had a bunch of the
> FreeBSD folks over here for a BBQ a couple days ago (they want you at the
> next one Clem).  We got to talking about Mach and someone told me that in
> the FreeBSD tree the Mach code was gone through and 60% of was deleted and
> it still worked.  It just seems like the Mach folks wanted to try this,
> and that, and then next thing and never went back to clean up the mess.

Welcome to academic/research code.  :-)

I'm reminded of a description of the Coda File System by Peter Braam;
he said that it was irretrivably tainted by a dozen Ph.D. students
working on their thesis.  Naturally, once they had done the necessary
work for them to get their doctorate, any interest in doing the
necessary code cleanup for their various experimental efforts
evaporated.  He tried cleaning it up, and eventually gave up and
decided to the only solution was a rewrite and redesign from scratch....

I used to be annoyed when professors and their graduate students would
do their work based on same ancient version of Linux.  (In general,
the last version of Linux dating from the professor had time to hack
on code.)  I later decided that was a feature, not a bug, because it
meant no one would be tempted to take academic code and try to put it
into the mainline kernel...

						- Ted