Conclusion
The impact of the relocation operation on CPU usage.
The left part of Figure 1 reflects
the CPU constrained situation for the Linux™ guests
running the other workloads, as visible through the comparatively
high steal values.
Note: Each of the guests can at most consume the
processing capacity of one CPU because only one virtual CPU is configured
for each of them.
The center part of Figure 1 shows how a small impact of the relocation operation, as z/VM® needs additional processing resources to perform the relocation of the guest running the transactional database workload.
Once the CPU intensive workload is relocated to the target z/VM host, the source z/VM host now disposes of sufficient CPU resources to support the CPU demand of the remaining guests running the other workloads, as is apparent from the negligible steal value during the after relocation phase in Figure 1.
The unused CPU power represented by the grey area at the top of the diagram results from the file system I/O workload waiting for I/O operations to complete.