On Tue, 30 Jan 2018, Paul Ruizendaal wrote:
“One widely distributed (though undocumented) solution
to this hardware
limit on the model 40 was a version of Unix by Robert Sidebotham,
Faculty of Environmental Design, University of Calgary. His solution was
to move the I/O buffers out of kernel space.”
I wonder if that inspired the AUSAM buffer management? The current buffer
header was "b" (like "u") which got mapped by KISA5.
For the first time I was able to avoid our 11/40 deadlocking; I can't
remember all the devices that were on it, but there were a *lot*
(including the printer driver etc which used the buffer pool, not the
character queue).
--
Dave Horsfall DTM (VK2KFU) "Those who don't understand security will
suffer."