Systems software technology and business
“People’s distrust of the high-pressure engines was confirmed when the boiler of a stationary engine exploded at Greenwich on 8 September 1803. It was the usual tale; the boy who had been trained to work the engine went off to catch eels and a labourer stopped the engine without releasing the safety valve.” Richard Hills, [...]
The subject of priority inheritance has come up again on the Linux kernel mailing list and Torvalds correctly notes
“Friends don’t let friends use priority inheritance”. Just don’t do it. If you really need it, your system is broken anyway.
“Priority inheritance” is similar to “soft real-time” in that both are efforts to avoid building software to [...]
A couple of years ago, one of our salesmen asked us to comment on a comparison between VxWorks and RTLinux performance that had a prospective customer worried. When we tracked down the article, we were dumbfounded that it was being taken seriously. The article was a student paper from a mid-level class in Networks with [...]
You can find an article on writing real-time control loops in RTLinux inside the giant Hristu-Varsakelis, Levine Handbook of Networked and Embedded Control. The article is by Edgar Hilton, Matt Sherer and myself and covers simple loops, loops with data and control going to the non-real-time “client” and loops using the Interface Kit [...]
One of the longstanding problems with operating systems is that there is no way to validate their correctness in the same way that engineers can calculate the ability of a beam to carry a weight or a wire to carry a current. Well, the problem is worse than that, because we don’t even have a [...]