On Thu, 11 Jun 2020 at 14:45, David Brownlee <a...@absd.org> wrote: > > The big issue with the Hydra was its lack of cache coherency between > processors, which made conventional SMP somewhat... challenging. You > could do very cool multiprocessor stuff with it, just not in a > conventional SMP capable OS (I remember talking to someone trying to > use it under NetBSD at the time :)
Oh my word! It reminds me of the late-generation MacOS-license-programme multiprocessor Mac clones such as the Daystar Genesis MP: https://everymac.com/systems/daystar/mp_plus/genesis_mp466_plus.html https://everymac.com/systems/daystar/mp_plus/genesis_mp932_plus.html A multiprocessor machine dedicated solely to running a single-processor OS... so that the extra CPUs could only be used by a handful of specialised apps, such as image filters. I think the Mac clones were basically designed to run a couple of specific Adobe Photoshop filters very very fast and basically nothing else. The chap that wrote the wonderful XPostFacto tool that got early versions of Mac OS X running on old, unsupported models of Mac did get OS X booting on some of the clones, but only on 1 CPU. It's a pity -- a maxed-out 4-CPU MP might have been a rather nice box for running MacOS 10.2 or 10.3 on. https://eshop.macsales.com/OSXCenter/XPostFacto/Framework.cfm?page=XPostFacto3.html -- Liam Proven – Profile: https://about.me/liamproven Email: lpro...@cix.co.uk – gMail/gTalk/gHangouts: lpro...@gmail.com Twitter/Facebook/LinkedIn/Flickr: lproven – Skype: liamproven UK: +44 7939-087884 – ČR (+ WhatsApp/Telegram/Signal): +420 702 829 053