Mike ... you said: > I looked at VMWare and liked it, I liked it a lot - but it doesn't "really" > present a virtual machine with virtual hardware like mainframe VM does, at > least not 100%. ...
I've got to take issue with this, the terminology. >From the definition of virtualization that I know, what VMware does *is* the real thing. That is, it lets the guest operating system run on the underlying hardware until there is an exception. Lack of (or limitted) PCMCIA support is a great point, but it is a fault which z/VM shares, if you consider such things as the sysplex timer or FCP (on releases of z/VM prior to the last two). So the point is that "virtual machines" are virtual in the same sense as "virtual memory" is virtual: it is real (possibly with translation) until there is a fault. This gives a clear and useful delineation between hypervisors and emulators. By this definition, what Java uses is not a virtual machine. That's bad. Can't do much about that. Quite frustrating. Nothing wrong with that the Java guys are doing per se, just hard to convey the value of a hypervisor with overloaded terms. > If they ever support dedicating NICs and PCMCIA devices to "virtual > machines" I'll definitely give it another look. ... I share the sentiment, the need for this feature. (That is one of the reasons for starting the thread, which has strayed somewhat!) A generic hypervisor "attach" command would be a great tool to have, something that would work the same on VMware as it does already on z/VM. -- R;
