Summary of Key Findings
This section summarizes key z/VM 7.1 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 7.1.
To compare the performance of z/VM 7.1 to the performance of previous releases, IBM ran a variety of workloads on the two systems. For the base case, IBM used z/VM 6.4 plus all Control Program (CP) PTFs available as of February 1, 2018. For the comparison case, IBM used z/VM 7.1 at the internal May 24, 2018 level. The runs were done on a mix of z13 and z14.
Regression measurements comparing these two z/VM levels showed z/VM 7.1 parity compared to z/VM 6.4. ETRR had mean 1.001 and standard deviation 0.023. ITRR had mean 1.010 and standard deviation 0.051.
Key Performance Improvements
In our dump enhancements article we describe the performance effect of several recent improvements to dumping. As workloads' storage footprints have become larger, it has become increasingly important to improve the performance of dumping. The article shows that for a sizeable workload run in a 1024 GB LPAR, dump size was reduced by 99% and time to dump was reduced by 97%.
Other Functional Enhancements
With the change to continuous delivery, functional enhancements are delivered as SPEs instead of holding them for a release boundary. To read about enhancements delivered as SPEs on top of z/VM 6.4, see the z/VM 6.4 report.