[erik_seaberg]

Sounds like IMS runs on Z system mainframes with redundant hot-swappable CPUs and memory. They pay IBM a lot of money for the illusion of a single reliable machine, when a different OS would manage it as a small cluster.

We economize by using racks of cheap, flaky commodity hardware, but we have to be ready for one computer to die by failing each application over to another.

[kragen]

in 01973 the s/360 did not have hot-swappable cpus or memory

even in the 01990s i don't think ibm had such an offering, though tandem did (but it couldn't run ims)

[jpgvm]

it didn't run ims but it ran nonstop SQL instead which was a rdbms designed for their redundant hw architecture

[kragen]

right, i didn't mean to imply it didn't support acid