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Sharing Devices Under z/VM

When z/OS runs as a guest under z/VM, the way z/VM handles reserve/release processing can affect the integrity of resources needed by z/OS. Therefore, take these factors into account when you are running z/OS as a z/VM guest:

• Make sure that host z/VM systems forward serialization requests to DASD hardware so that the DASD hardware can perform serialization.

  This process, which serializes access among several real processors that are sharing a device, is known as real reserve/release processing.

• Use the z/VM virtual reserve/release processing feature to serialize access among systems that are running as guests under the same z/VM operating system.