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SMP_CPU_BITMAP is a system parameter that indicates that the corresponding CPU is a bitmap representing up to 1024 CPUs. Each bit set in this bitmap indicates that the corresponding CPU automatically attempts to join the active set in an OpenVMS symmetric multiprocessing environment when the instance is booted. A cleared bit indicates that the corresponding CPU is ignored only at boot time; if it is otherwise viable, the CPU can be started at a later time. SMP_CPU_BITMAP defaults to all bits set. (CPU 0 through CPU 1023 are enabled for multiprocessing.) Note that the primary processor is always booted regardless of the setting of the corresponding bit in the CPU bitmap. To change the value of SMP_CPU_BITMAP in SYSBOOT or SYSGEN, specify a list of individual bits or contiguous groups of bits. For example: SYSGEN> SET SMP_CPU_BITMAP 0,5,17-21 The command in this example sets bits 0, 5, 17, 18, 19, 20, and 21 in the bitmap and clears all other bits. This parameter replaces the SMP_CPUS parameter.