alt Hacker NewsThe 286 worked perfectly fine. If you take a 16-bit unix and you run it on a 286 with enough memory then it runs fine.
Where it went wrong is in two areas: 1) as far as I know the 286 does not correct restart all instruction if they reference a segment that is not present. So swapping doesn't really work as well as people would like.
The big problem however was that in the PC market, 808[68] applications had access to all (at most 640 KB) memory. Compilers (including C compilers) had "far" pointers, etc. that would allow programs to use more than 64 KB memory. There was no easy way to do this in 286 protected mode. Also because a lot of programs where essentially written for CP/M. Microsoft and IBM started working on OS/2 but progress was slow enough that soon the 386 became available.
The 386 of course had the complete 286 architecture, which was also extended to 32-bit. Even when flat memory is used through paging, segments have to be configured.
The 286 worked perfectly fine as an improved 8086, for running MS-DOS, an OS designed for 8088/8086, not for 286.
Nobody has ever used the 286 "protected mode" in the way intended by its designers.
The managers of "extended memory", like HIMEM.SYS, used briefly the "protected mode", but only to be able to access memory above 1 MB.
There were operating systems intended for 286, like XENIX and OS/2 1.x, but even those used only a small subset of the features of the 286 "protected mode". Moreover, only a negligible fraction of the 286 computers have been used with OS/2 1.x or XENIX, in comparison with those using MS-DOS/DR-DOS.