Timothy Sipples writes that in certain situations, software licensing charges for zVSE 4.1 on the mainframe will actually drop. The operating system, which stands for Virtual Storage Extended, is less common than z/OS, the mainframe’s major operating system. It tends to run on smaller versions of Big Iron but has been around for more than 40 years.

We wrote about zVSE 4.1 in March when it first became generally available. We quoted Pete Clark of CPR Systems, which provides education on mainframe operating systems, as saying that some customers might be able to get cheaper licensing costs under particular schemes.

The sub-capacity option allows mainframers to pay for the MIPS that they use on z/VSE, rather than being charged for how many total MIPS are on the box. Sipples really spells out those different schemes in his post.

Basically, by using the sub-capacity pricing option on zVSE, which is new with version 4.1, mainframe users can reduce their costs by staying within certain MIPS ceilings. You can dig into it yourself by checking out IBM’s Midrange Workload Licence Charges.

…if you buy a B01 and run z/VSE V4.1’s Central Functions, you can actually lower your software bill if you can live within a roughly 20 MIPS softcap. Previously the best you could do with z/VSE V3 was about 26 MIPS (z890 110 or z9 BC A01) full capacity. A 20 MIPS softcap inside a 38 MIPS machine is quite nice: you have room to grow, and softcaps allow temporary spikes above 20 MIPS.

Sipples concluded by saying that “it’s nice to see IBM offer a much better package for its smallest VSE customers.”