Functions Incompatible With Parallel Access Volumes; Parallel Access Volumes Shared Across Multiple Sysplexes; Considerations For Using Compatible Super Pav; Performance Design Of Compatible Super Pav - HPE XP7 User Manual

Functions incompatible with Parallel Access Volumes

Devices using Parallel Access Volumes, Hyper Parallel Access Volumes, or Compatible Super PAV
cannot be used concurrently with the following functions:
• Data Exchange
• Open Volume Management
• Cache Residency
• Business Copy (open system version)
• Continuous Access Synchronous (open system version)
• Continuous Access Journal (open system version)
• High Availability
The devices using any function other than Data Exchange of the functions listed above can coexist in the
same CU with devices using Parallel Access Volumes, Hyper Parallel Access Volumes, or Compatible
Super PAV. However, the devices using Data Exchange cannot coexist in the same CU with devices
using Parallel Access Volumes, Hyper Parallel Access Volumes, or Compatible Super PAV.

Parallel Access Volumes shared across multiple sysplexes

You can share Parallel Access Volumes functionality across multiple sysplexes on a storage system.
To share static PAV, all connected systems must be in compatibility mode. To share dynamic PAV, the
following requirements and restrictions apply:
• Only one sysplex must be running in Dynamic Alias Management mode. This master sysplex is the
only sysplex connected to the storage system that assigns aliases.
• For all other connected sysplexes, set the WLMPAV (HCD) and Dynamic Alias Management (WLM)
settings to No.
NOTE: If you have enabled Dynamic Alias Management for more than one sysplex, unsynchronized alias
transition and unpredictable response times may occur.
For more information about setting the WLM mode, Setting the WLM operational mode.

Considerations for using Compatible Super PAV

When using Compatible Super PAV, the following performance design, cautions, and restrictions are
required.

Performance design of Compatible Super PAV

The Compatible Super PAV feature enables you to use alias volumes in a different CU from the one that
contains base volumes. Therefore, when Hyper Parallel Access Volumes is used, if you enable
Compatible Super PAV, the throughput performance improvement can be expected by increasing I/O
multiplicity. On the other hand, as the I/O multiplicity for base volumes increases, the load on the
processor and the amount of data per unit time against base volume might be increased. These might
cause the following effects:
Effects on using Compatible Super PAV:
Functions incompatible with Parallel Access Volumes 15