We run Linux guest images on z mainframe hardware. It’s extremely efficient and cost effective.
How does it compare to things like running Linux VMs on VMWare from a cost perspective? I realize that costs aren't really everything, as IBMs mainframe infrastructure is very mature, so things like backup, upgrades and stuff is well developed.
I remember back when IBM was first really starting to jump onto the Linux bandwagon, and they had a mainframe spin up some thousands of Linux images on one box. At the time, it was damned impressive demonstration IMO, even though there probably wasn't a whole lot of resources available for each individual instance. IBM has been doing LPARs for a long time.