Maybe it's just me, but after the huge set of world-changing things in 1978's CACM, it seems like not so much in 1979. Also, in minor grumbles, I didn't find a picture I liked in either of the papers I decided to cover.
One that inevitably caught my eye because of the first author is David Cheriton's Thoth. It's a complete, though fairly simple, OS, designed and built with the goal of being portable across machine architectures. It includes (and depends on) a compiler for a custom language. The language is apparently named "Eh", but they refer to it as "the base language" throughout the paper. It's a descendant of B & BCPL, which should put it closer to C than not, but the syntax is actually rather different. It assumes that integer pointers are themselves consecutive integers; the language doesn't support the notion of a byte pointer, because at least one of the machines they wanted to target didn't support byte pointers.
The file system is a tree that supports UNIX-like mount points, cleverly called "grafts", but otherwise the file naming seems like something from a parallel universe, when viewed from 2025. Among other things, the root of the FS is called "*", so "*/src" refers to what in UNIX terms would be "/src".
There is a function for creating a "process", but its first argument is a pointer to a function. Their "processes" are actually closer to modern threads, and share an address space. The OS includes support for multiple address spaces; the set of "processes" in one address space is a "team". Support for multiple teams can be compiled in or out, assuming the hardware has an MMU and virtual memory.
There is no support for multiprocessors, though they claim and I believe that it wouldn't be too hard in the OS itself. A process runs until it blocks, so multitasking is cooperative.
They achieved the goal of portability of software and the OS; Thoth ran on both the Data General Nova 2 (released in 1973, already not a new machine by the time of this paper) and the TI 990/10, both 16-bit machines, and so Thoth was designed around those limitations despite the goal of portability. I think it's arguable whether the system would meet the goal of portability to a later architecture; I would say it was focused on that pair of specific systems rather than truly working toward a system with open-ended future portability.
Overall, maybe not so much to write home about, though Cheriton's later work on V is claimed to be a "successor" to Thoth, and is of huge importance in the history of distributed systems.
Of note for similar reasons is Dorothy Denning's proposal for a hardware gadget that does RSA encryption and allows a PC to encrypt data it sends to a centralized file server (CF), as well as to securely exchange files with another PC via the CF. Some of the functions appear to be transparent to the PC, others don't. Ultimately using RSA as the only encryption mechanism is computationally intensive, although at the time, according to Denning, Rivest himself claimed there would soon be high-performance hardware implementations.
There were a few other things here in there in 1979, but nothing that really compels me to talk about. As always, of course, my primary strength is the systems work; I can't comment as fluidly or recognize the importance as clearly when dealing with algorithms and theory.
(On a personal note, I think 1979 was the year I got my TRS-80 Model 1, using a Zilog Z80 16-bit CPU. A simple and interesting machine.)
