VSHARE consists of three basic components:

• The first component executes in the batch programs area—it intercepts the I/O requests and ships them to the second component of VSHARE residing in CICS

• The second component of VSHARE resides in the CICS region owning the VSAM files—it performs all of the VSAM I/O on behalf of the batch job



• The third component of VSHARE also resides in the CICS region—it comprises a series of online programs providing the following functions:
• Define CICS regions to use VSHARE
• Define jobs eligible to use VSHARE
• Monitor active jobs currently using VSHARE
• Suspend a job that is currently active
• Restart a job previously suspended
• Cancel a job
• Reduce the rate of I/O requests being sent to CICS in the event of heavy online activity
• Review prior executions of batch jobs

VSHARE communicates using VTAM and z/OS Cross Memory Services

• VTAM can be used when the batch job and the CICS regions reside on the same or different CPUs.

• Cross Memory Services provides a performance boost but the batch job and the CICS region must be in the same z/OS system.

z/OS 2.3 Compatible