PHYSICAL_MEMORY specifies the amount of physical memory available
    for use. The default setting is -1, which equates to all memory
    in the system. Decreasing this parameter allows you to test
    smaller configurations of memory without having to remove memory
    boards.

    This special parameter is used by VSI and is subject to change. Do
    not change this parameter unless VSI recommends that you do so.

    Because of hardware configuration requirements on the AlphaServer
    ES47/ES80/GS1280 systems, VSI does not recommend altering the
    setting of the system parameter PHYSICAL_MEMORY from its default
    setting of -1. Artificially reducing the amount of memory can
    produce unpredictable results on these systems.

    PHYSICAL_MEMORY is an AUTOGEN parameter.