Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!wuarchive!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!dsinc!bagate!cbmvax!jesup From: jesup@cbmvax.commodore.com (Randell Jesup) Newsgroups: comp.unix.amiga Subject: Re: Adding Symmetric Multiprocessing to Amiga UNI Message-ID: <18351@cbmvax.commodore.com> Date: 31 Jan 91 08:20:36 GMT References: <994@swrinde.nde.swri.edu> > <20708@hydra.gatech.EDU> <1991Jan30.181208.1256@convex.com> Reply-To: jesup@cbmvax.commodore.com (Randell Jesup) Organization: Commodore, West Chester, PA Lines: 36 In article <1991Jan30.181208.1256@convex.com> swarren@convex.com (Steve Warren) writes: >I am assuming that an '040 board would include on-board memory designed >to function optimally with an '040. In this case you would want the '040 >to favor the coprocessor ram over the motherboard ram. You would also >want the '040 to release the bus on the motherboard when it is operating >out of coprocessor ram. Even a simple '040 implementation would have similar effects due to the large cache of the '040. An '040 with external cache would be even less affected, though probably still would be affected more than the local- memory version. An external cache might be faster having local '040 memory if the '030 isn't being used. >I/O processing should also be performed on the '030. The SCSI controller is >on the motherboard, and it just makes sense to put all the housekeeping out >on the secondary processor. Yes, though this requires a fair bit of coding... (understatement of the day). >It would be nice if some utilization of the custom chips were possible, since >they do have line drawing and other capabilities. For "simple" blits (scroll, etc) an '030/'040 is probably faster than the existing blitter ('040 wouldn't be much faster than '030). For complex blits, longish lines, patterned fills, etc, the blitter is faster. (Short lines and restricted-shape solid-filled polygons are faster on the processor, even in some cases for 68000's, assuming there's nothing else the CPU could be doing.) -- Randell Jesup, Keeper of AmigaDos, Commodore Engineering. {uunet|rutgers}!cbmvax!jesup, jesup@cbmvax.commodore.com BIX: rjesup The compiler runs Like a swift-flowing river I wait in silence. (From "The Zen of Programming") ;-)