UNIX* on IBM machines running VM

[Ian F. Darwin]

>I am interested in information about UNIX running on IBM machines.
>I am particularly interested in the new AT&T product SYSTEM V-VM and
>how it compares with the Amdol implementation.

The Amdahl (note spelling) port IS the AT&T System V-VM under
a new name. Same product, same performance, same completeness.

This product is now available as Amdahl's UTS/V, running under
VM/SP. There is a `real soon now' version called UTS/N, that runs
native mode; it is only supported on Amdahl hardware (you thought
the diffs between PDP-11 CPUs were bad? look at the diffs between
IBM/370 series CPUs - not in the instruction set so much as in
the `machine check' (hardware error) handling).
A more interesting comparison would be between the Amdahl/AT&T
port and the IBM port, `IX-370'. Among the salient differences,
the Amdahl one supports IBM 3270 terminals, while the IBM one
does not! However, the Amdahl one is not supported on IBM 3705
front-end processors, since Amdahl doesn't own one to test it on.

Anybody have a full, reasonably unbiased comparison between
the two commercially-available ports (there are others, such
as one done for a heavily-modified TSS, that are not really
available outside certain parts of AT&T)?