Path: utzoo!attcan!uunet!sco!johnwe From: johnwe (John Weber, Celtic sysmom) Newsgroups: comp.arch Subject: Re: Transputer based systems. Summary: Transputer problems Keywords: transputer, inmos, unix Message-ID: <1133@scovert.sco.COM> Date: 23 Sep 88 21:40:34 GMT References: <253@uceng.UC.EDU> Reply-To: johnwe (John Weber, Celtic sysmom) Followup-To: comp.arch Distribution: na Organization: The Santa Cruz facility for the curably sane Lines: 49 In comp.arch, rsexton@uceng.UC.EDU (robert sexton) discourses on Transputer based systems., thusly: > being a fan of parallel system and their advantages, I was wondering why > the transputer has not gotten off the ground as a viable system. It seems > pretty feasable, as well as very cost-effective. I imagine a machine with > several transputers, each running unix. The major problem with transputers in a multi user (UN*X ish OS) environment is the complete lack of memory management, or any provision for external memory management. While this is all well and good for a single user PC, where nobody really cares if one process stomps another process, it is not really the acceptable answer for a multiuser system or a system on a network. If a process breaks in just the right way, it could take out the whole network. There is also the problem that a user can control task switching, and can effectively shut it off, with a little thought. This is also a bad thing. The processor also has a few design things which I personally feel a bit uncomfortable with, such as a lack of a barrel or funnel shifter combined with a bit of a problem in the microcode which causes the processor to hang for a LONG time if you try to left shift 7fffffffh, or distinctly too few registers. I also have a bit of a problem with the message security. On the other hand, they are wonderful chips for parallel processors, controllers, and PCs. Massively fast, hardware multitasking, and other wonderful things. Basically, in any aplication where interprocess security is not needed they, are great. > Thanks in advance for your input. > No prob... > > Robert Sexton, University of Cincinnati > rsexton@uceng.uc.edu tut.cis.ohio-state.edu!uccba!uceng!rsexton > Box Full O' Transputers... The Breakfast with MIPS > I do not speak for UC, They don't speak for me. -- "In the fields of Hell, John Weber, ...!uunet!sco!johnwe where the grass grows high, @ucscc.ucsc.EDU:johnwe@sco.COM are the graves of dreams, allowed to die." -- Author unknown Celtic sysmom with an ATTITUDE! Any opinions expressed are my own, and bear no relationship to those of my employers, to the best of my knowlege.