Your OSF/1 link makes a lot of references to Mach 2.5 which still required the Unix portions to be in kernel memory space so it was still a monolithic kernel. This was the same as NeXTSTEP which is the basis for the current Mac OS X. It looks like OSF/1 did move to Mach 3.0 which was a microkernel but I'm not sure if the Digital Unix / Tru64 moved to that or not.
As for AIX, I used it on an RT around 1990 and then POWER based RS/6000 machines in the 1990's. It was a monolithic kernel.
Your own link mentions the failed Mach based Workplace OS and all the different "personalities."
From your link:
Internal discussion at IBM focused on AIX. Finally, at Comdex in 1993, IBM Chairman Louis Gerstner announced that the microkernel would not replace AIX. IBM realized that many AIX users would not accept performance penalties associated with microkernel systems. IBM was also concerned with the microkernel presenting a competitive impediment against high performance HP or Sun Unix systems than ran directly on the hardware. Instead, Gerstner told AIX customers that they would be able to migrate to Workplace OS, later if they were interested.
> With the introduction of the ESA/390 architecture, AIX/370 was replaced by AIX/ESA[28] in 1991, which was based on OSF/1, and also ran on the System/390 platform.
I think another way to look at it is that "AIX" is a larger term for a family of operating systems. The one that I used and probably the most popular was the monolithic kernel based on System V Unix that ran on the RT and POWER architectures.
The AIX version that would run on Mach for workstations was never commercially released. The AIX version for mainframes was based on Mach but AIX/ESA. You can see other versions like AIX/386
As for AIX, I used it on an RT around 1990 and then POWER based RS/6000 machines in the 1990's. It was a monolithic kernel.
Your own link mentions the failed Mach based Workplace OS and all the different "personalities."
From your link:
Internal discussion at IBM focused on AIX. Finally, at Comdex in 1993, IBM Chairman Louis Gerstner announced that the microkernel would not replace AIX. IBM realized that many AIX users would not accept performance penalties associated with microkernel systems. IBM was also concerned with the microkernel presenting a competitive impediment against high performance HP or Sun Unix systems than ran directly on the hardware. Instead, Gerstner told AIX customers that they would be able to migrate to Workplace OS, later if they were interested.
https://en.wikipedia.org/wiki/IBM_AIX#IBM_mainframes
> With the introduction of the ESA/390 architecture, AIX/370 was replaced by AIX/ESA[28] in 1991, which was based on OSF/1, and also ran on the System/390 platform.
I think another way to look at it is that "AIX" is a larger term for a family of operating systems. The one that I used and probably the most popular was the monolithic kernel based on System V Unix that ran on the RT and POWER architectures.
The AIX version that would run on Mach for workstations was never commercially released. The AIX version for mainframes was based on Mach but AIX/ESA. You can see other versions like AIX/386