davecb@yunexus.YorkU.CA (David Collier-Brown) (10/22/90)
lindsay@gandalf.cs.cmu.edu (Donald Lindsay) writes: >Multics needed hardware support for rings. The ring idea was long >ago replaced by capabilities - a concept that relates well to the >recent interest in objects. Multics also need hardware support for its cache (!)... All too many things pushed the state of the art at that time. Some capability/object machines have >been built, and even sold. (Does anyone know how to characterize the >Biin machine?) HOWEVER, I have seen a number of success stories >where capabilities were supported entirely in software. It would be >interesting to discuss efficency, and portable OSes, in this more >modern context. Interestingly, the Honeywell machine that replaced Multics was a DPS-8 woith capability hardware, running GCOS. It worked **so very well** that individual developers got private copies of ``shared'' so that their errors wouldn't crash the OS. Not too sucessfull an implementation, methinks (:-)) --dave -- David Collier-Brown, | davecb@Nexus.YorkU.CA, ...!yunexus!davecb or 72 Abitibi Ave., | {toronto area...}lethe!dave or just Willowdale, Ontario, | postmaster@{nexus.}yorku.ca CANADA. 416-223-8968 | work phone (416) 736-5257 x 22075