Re: [TUHS] First Unix-like OSes not derived from AT&T code?

in blue On Mon, May 2, 2022 at 2:57 AM Ron Natalie &lt;ron(a)ronnatalie.com&gt; wrote: Correct -- AIX for the 370 ISA and 386 were compiled from the same code base Not quite correct. TCF was based on the ideas from the Locus Distributed OS. But not the same code. The Locus Distributed OS was based on a research (V7) kernel originally on 11/70s; although I believe UCLA added BSDism over time and Vax support (I never saw that personally). But more importantly, AIX and TCF itself were also owned by IBM (*i.e.* it was a work for hire of LCC for IBM). Bruce Walker was the implementation lead for both (and one of Jerry's grad students). Locus TNC (which is what OpenSSI for Linux is based on[1]) - although the website seems to be taken down sadly - it never was ported beyond Linux 2.6 kernel) is a completely new implementation yet. I'm one of the architects of the same. We were 'firewalled' so Bruce and our peers could talk about things, but I was never allowed to actually look at the IBM code base. I could >>use<< it to try things out. After the IBM AIX contract ended, Bruce and the old AIX team at LCC was then given full access to TNC source trees which Locus owned the IP. The big difference between the 3 was the Locus was its own OS, that supported UNIX-like features. Whereas TFC was built into a modified/custom AIX kernel and special FS with ad hoc support for the different issues that allow process migration. One of the cool things as Ron pointed out was the TCF allowed the mixing of binaries from Intel and IBM ISAs and the kernel would use whatever processor it needed. With the 3rd generation TNC, the technology was split into 14 separate 'products' that used structured interfaces in the kernel. For instance, the process support was encapsulated in what we called VPROC (similar to the multiple FS style layers from Research and later Sun -* i.e.* the different VFS) and while it worked better if you used the Locus supplied cluster file system (which supported full Unix semantics), basic process migration within the constraints that NFS placed, also worked (the HP implementation was based on NFS, while DEC, Intel, and SRVR4 implementations used CFS). My personal role was much of CFS and some of the utility functions like the Cluster Management System (CMS). In fact, a small demonstration of TNC was done with OS/2 to show that the OS/2 process semantics and the UNIX process semantics could co-exist, but it was never completed as IBM did not buy it. However, some of the technology landed in the Rochesters AS/400 OS in their Posix emulator which Locus also had a hand in building. One of my favorite demos was at a trade show that had a LAN; our folks would bring a PS/2 with an empty hard disk and load a single floppy. Boot the kernel, and add it to the TCF cluster back at LCC. The system immediately was usable, although since the disk was not populated, all binaries had to come across the LAN/WAN. But the caching would start to take over in the background and slowly populated a local copy of /bin, /lib, and the like. Very cool ... Clem [1] Sadly, when I checked this AM, the OpenSSI website seemed to be taken down. I d not believe OpenSSI was ever beyond Linux 2.6 kernel. IMO: It was a shame that the upstream Linux kernel team had been willing to take the VPROC changes, it would have been a very interesting and exciting system enhancement. As Ron said, anyone that used TCF or TNC was pretty much hooked. I'll have to do some more poking to find out what happened.