Base Processor?

[Don W.]

When you set up the directory entry for a z/OS guest with multiple virtua
l
CPU's (e.g. CPU 00, CPU 01) and you QUERY CPUS, CPU 00 shows as BASE. Wha
t
is the difference between a BASE CPU and a non-BASE CPU? Does it really m
ake
any difference in this environment. In terms of real processors, at one t
ime
the base processor had to do the I/O. I do not believe that is true any
more. Am I correct? and when did that stop being the case?