Kernel mods and RTIngres

[Joe Kalash]

> > ... RTI has to support their system on a multitude of systems.
> 
> Bogus!  Other vendors seem to be able to design software to cope
> with a variety of systems without asking one to modify his kernel.
> For example, one can write per-system-type user-mode "lock"
> interface modules that work acceptably well.

Really, how does one write such wonderful beasties? Indeed, what
do you mean? You have lots of buzz words, but you didn't say anything.

> 
> Not only that, but when RTI made our Ingres users install their
> lock driver, it turned out that their software still didn't
> support concurrent database updates!  What was the point of the
> lock driver??

The point of the lock driver is to keep two people from updating
the same relation at the same time. If I do a "give everyone a
10% raise", at the same time you are doing a "Give everyone in
the shoe department a 5% raise", if these two updates do not
start and finish independently some employees in the shoe dept.
could get a 10% raise, some could get a 5% raise, and some could
get a 15.5% raise. Not uselly considered useful.

			Joe Kalash
			kalash at berkeley
			ucbvax!kalash