Summary of Key Findings
This section summarizes key z/VM 7.3 performance items and contains links that take the reader to more detailed information about each one.
Further, the Performance Improvements article gives information about other performance enhancements in z/VM 7.3.
For descriptions of other performance-related changes, see the z/VM 7.3 Performance Considerations and Performance Management sections.
To compare the performance of z/VM 7.3 to the performance of previous releases, IBM ran a variety of workloads on the two systems. For the base case, IBM used z/VM 7.2 plus all Control Program (CP) PTFs available as of March 14, 2022. For the comparison case, IBM used z/VM 7.3 at the internal April 27, 2022 level. The runs were done on z15.
Regression measurements comparing these two z/VM levels showed z/VM 7.3 parity compared to z/VM 7.2. ETRR had mean 1.002 and standard deviation 0.013. ITRR had mean 1.002 and standard deviation 0.012.
Key Performance Improvements
z/VM 7.3 is largely a rollup of service (PTFs) available for z/VM 7.2. Thus there are no big performance improvements in z/VM 7.3 per se. Among the performance PTFs for z/VM 7.2 were Dynamic Memory Downgrade, 4 TB Exploitation, and z/HPF I/O for Dumps. For discussions of the other z/VM 7.2 PTFs evaluated, refer to the z/VM 7.2 section in the table of contents.
Other service available for z/VM 7.2 extended the HyperPAV and z/HPF disk performance technologies to minidisks. For citations of these, see our z/VM 7.3 improvements page. We did not evaluate those specific PTFs because the performance properties of HyperPAV and z/HPF are already understood.
Other Functional Enhancements
Beyond work done for performance, to read about enhancements delivered as new-function APARs, see the z/VM new function page.