Java on mainframes

Question

I work for a large corporation that works with a lot of x86-based servers on which we run the JVM.

We have successfully experimented with VMWare ESX to better utilize our data center. But they still consume a lot of power on the processor.

I had a crazy idea that we should resurrect mainframes, we could host either a lot of JVMs, or virtual machines.

Has anyone tried this? Are there any good benefits?

Are you losing flexibility? For example. we have mainframes in other parts of the company, but they seem to have a much tougher use of machines. Lots of change control, long lead times, etc.

Answer 1

All this assumes that you are talking about Java on Z / OS and not running Linux virtual machines on the mainframe to take advantage of the cost savings that come with fewer machines.

My thoughts on virtualization are at the end of this, and probably about which path you want to look at, but I start with Z / OS since then, with which mainframes are traditionally associated and with which I am familiar. I have some experience with the Java mainframe.

Short answer: it depends, but probably not. What are your apps? Mainframe is a complex environment compared to x86 servers. If you work with heavy I / O loads under something like Websphere, it may be worth the fact that your mainframe is underutilized.

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