Hacker News Reader

Comment by code_duck | Hacker News Reader

The 386 was not available in 1983... The 286 was released in 1982. Linus was partially working on Linux initially to get to know the processor in his new machine, the 386.

Anyhow, I don't know why a 386 processor is required for people to want to run Unix. Unix was well established as 'the' OS for serious computing, and MSDOS was not a great alternative. Actually, MicroSoft released a lousy *nix themselves in 1980: http://en.m.wikipedia.org/wiki/Xenix

So, the idea of running Unix on PC software was mot unusual and made plenty of sense. Not necessarily for home users, but for small businesses and education professionals, who have been a significant market for personal computers all along.

View on HN

The 386 has an MMU, making it feasible to do preemptive multitasking and virtual memory.

The 286 and 8086 had multitasking based on allowing small programs to run concurrently, but nothing that used a lot of memory.

The competing 68000 also lacked an MMU. The later 68010, I think, had the MMU.

The lack of preemptive multitasking didn't mean that people didn't want to run a Unix-like OS at home, if that's what you mean. MSDOS was horrible, and regardless of the capabilities of your machine one would probably rather use something else.

I had Amigas with 68000s, and one with a 68030. AmigaOS didn't have any special capabilities on a 68030 that it didn't have running on a 68000. AmigaOS was a Unix-like IS with full preemptive multitasking that could operate in 256k of address space, on a 68000.

Oh yeah, DOS sucked. I remember Xenix and MKS and some other unixy toolkit. Oh yeah also Coherent. I ran a shell called Gulam on an Atari, and it was nice. Fake pipes were better than no pipes :)

Did all the processes run in the same address space on the Amiga??

You could do preemptive multitasking with memory protection on a 286. IBM & MS did it in OS/2.

Actually looks like Xenix used that too. http://www.tenox.net/docs/microsoft_xenix_30_286_press_relea...

Really? I though OS/2 was on the 386. I thought that the 286 had some limit on the size of a process, but you could execute multiple processes. I don't know why, but I think it was 64k per process. Also, the other thing I recall was thinking that it was a nice idea.

I was only familiar with 68k so I'm probably wrong here.

Really.

The 286 is a 16-bit CPU so there would have been various memory limits. http://www.os2museum.com/wp/?page_id=313 has some details on what it can do, but not much mention of limits...

I ran minix on a 286.

[edit] Quick googling found instructions for installing on an XT with 1M RAM and a single 720k floppy:

http://www.minix3.org/iso.previous/Intel-2.0.3/xt/README

I had a 10MB hard drive, so didn't need to go through such gyrations (though I didn't upgrade to a 2nd MB of ram until later)

The 386 had both protected mode and a large enough address space to make that protected mode useful. The 286 had protected mode as well, but a 16-bit protected mode doesn't let you write programs large enough for it to be worthwhile.

Reply on news.ycombinator.com