PCA$HELP.HLB  —  Vectors  System Configurations
    The following illustrates the possible system configurations and
    their effect on performance:

    o  CPU1 and CPU2 with VVIEF support:

       Efficent for program development, but can be 3-5 times slower
       than the scalar performance. Cost-effective for parallel
       applications that do not use vector processing.

    o  CPU1 - CPU2 with Vector processor:

       Efficent vector performance: As soon as a processor issues its
       first vector instruction, VMS schedules it only for vector-
       present(VP) CPU2. If the process is executing on CPU1, VMS
       swaps out and gives it to CPU2. If CPU2 is not free, the
       process waits for it to become free: VMS does not use VVIEF
       on this system.

    o  CPU1 and CPU2:

       Fatal to vector programs. They will fail when the first vector
       instruction issues and neither VVIEF nor any other vector
       processors are present.

    o  CPU1 and CPU2 with Vector processors:

       Most efficent parallel-vector performance and cost-effective.

    o  CPU1 and CPU2 - CPU3 and CPU4 with Vector processors:

       Efficent parallel-vector performance.
Additional Information: explode extract
VVIEF on VAX Multiprocessors
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