On Mon, Jul 20, 2020 at 7:51 AM Larry McVoy wrote: > This isn't quite the same but Victor Yodaiken wrote a real time kernel > that ran all of Linux as a user process. Super cool idea and it worked > great, he would demo it sampling the parallel port while Linux was running > some X11 perf thing, tarring up /usr and untarring on nfs://server/tmp/usr > and doing a ftp transfer. Basically beating the crap out of Linux as > hard as he could while running a real time sampler and it never missed. > > Clem should pay attention, in my opinion, this is how you do Unix and > real time. Because Unix is time sharing and throughput, that is the > opposite of what real time is. Wedging real time into Unix is a mistake. > > http://mcvoy.com/lm/papers/rtlmanifesto.pdf As often true, I really don't disagree with you. Around the time I left Masscomp for Stellar we were working on a rewrite with some ex-CMU folks (Doug ... I don't remember is his last name now) that used a preemptive RT microkernel under the covers and then supplied RTU system calls. Tom and I left for Stellar and a couple of other people left too. This was time of the reign of Mr. Potato Head (ex-IBM guy that was named CEO) and things blew up.