VMS Help Sys Parameters, SMP_SANITY_CNT  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    SMP_SANITY_CNT establishes, in 10-millisecond intervals, the
    timeout period for each CPU in a symmetric multiprocessing (SMP)
    system. Each CPU in an SMP system monitors the sanity timer of
    one other CPU in the configuration to detect hardware or software
    failures. If allowed to go undetected, these failures could cause
    the cluster to hang. A timeout causes a CPUSANITY bugcheck.

    The default value is 300 milliseconds (30 10-millisecond
    intervals).