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HWPREFS(1)                BSD General Commands Manual               HWPREFS(1)

NAME
     hwprefs -- inspect and control low-level system and processor parameters

SYNOPSIS
     hwprefs [-v] [-h] [cpu_count={1..N}] [cpu_enable {1..N}] [cpu_disable {1..N}] [cpu_l2_cache={true,
             false}] [cpu_l3_cache={true, false}] [cpu_nap={true, false}] [cpu_hwprefetch={0, 4, 8}]
             [cpu_nop_dsts={true, false}] [memctl_readbypass={true, false}] [os_class] [os_type]
             [machine_type] [memory_size] [cpu_type] [cpu_freq] [cpu_bus_freq] [memctl_type] [ioctl_type"]

DESCRIPTION
     hwprefs inspects and controls low-level system and processor parameters

     -v       verbose mode

     -h       display help message

     cpu_count={1..N}
              number of processors available for use by MacOS X

     cpu_enable {1..N}
              enable a specific processor

     cpu_disable {1..N}
              disable a specific processor

     cpu_nap={true, false}
              processor nap

     cpu_l2_cache={true, false}
              processor L2 cache

     cpu_l3_cache={true, false}
              processor L3 cache

     cpu_hwprefetch={0, 4, 8}
              prefetch engines used by hardware prefetcher (PPC970 only):

              0 - all prefetch engines disabled, DST instructions treated as NOPs

              4 - four automatic hardware prefetch engines, four used by DST instructions

              8 - eight automatic hardware prefetch engines, DST instructions treated as NOPs

     cpu_nop_dsts={true, false}
              treat DST instructions as nops

     memctl_readbypass={true, false}
              memory controller (U3 only) read-bypass optimization (allows read commands to memory to bypass
              straight to read memory request queue, saving a significant number of cycles)

     os_class
              displays OS class {Cheetah, Puma, Jaguar, Smeagol, Panther, Tiger}

     os_type  displays operating system type

     machine_type
              displays machine type

     memory_size
              displays system memory

     cpu_type
              displays processor type and version

     cpu_freq
              displays processor clock frequency

     cpu_bus_freq
              displays processor bus frequency

     memctl_type
              displays memory controller type

     ioctl_type
              displays io controller type

Darwin                         December 21, 2005                        Darwin