Hyperstar

For a MIMplex that has 3 or more active systems, performance of Virtual Control Files may be improved by activating the Hyperstar feature. When this feature is active, a client system does not always transfer the VCF back to the master system after completing its processing. Instead, CA MIM examines a ‘look ahead list’ of systems waiting for the VCF. If the list is not empty, and the client has a CTC or XCF path to the next system in the list, the client transfers the VCF directly to that system instead of the master. When the ‘look ahead list’ becomes empty, or when there is no path to the next system in the list, the client transfers the VCF back to the master.

The primary effect of Hyperstar is to reduce the amount of VCF I/O performed by the VCF master system, in many cases by more than 50 percent; this in turn reduces the amount of CPU time that is used on the master system, and can potentially reduce the control file access times for all systems in MIMplex.