numa_mode(5)							File Formats Manual						      numa_mode(5)

NAME

       numa_mode - HP-UX kernel mode on NUMA servers

VALUES

   Default
   Allowed values
       Integer values or

DESCRIPTION

       HP-UX  can  operate  in	one  of two modes (LORA or SMP) when operating on ccNUMA (cache coherent Non-Uniform Memory Architecture) servers.
       LORA is the Locality-Optimized Resource Alignment mode.	SMP is the Symmetric Multiprocessor mode.  See for information on LORA mode.

       LORA mode is optimal when the underlying partition is configured according to the guidelines for  LORA  Partitions.  In	LORA  mode,  HP-UX
       attempts  to  align the allocation of memory and scheduling of processes within the minimal number of localities.  SMP mode is optimal when
       the partition does not meet the guidelines for LORA partitions. In SMP mode, HP-UX distributes the memory and CPU  allocations  across  all
       the localities.

       The tunable allows users to set the mode independent of the partition guidelines.

       There are 3 possible values for this tunable.

	      This value is the default value.
		     HP-UX evaluates the hardware configuration at boot time to determine the appropriate mode.  HP-UX automatically switches into
		     LORA mode when the partition meets the guidelines for LORA partitions; otherwise, it switches into  SMP  mode.   The  tunable
		     should also be set to zero to allow HP-UX to perform memory allocation in NUMA aware manner when HP-UX is set to LORA mode.

		     Use to determine the HP-UX mode of operation.

	      This value causes HP-UX to operate in LORA mode even if the partition does
		     not  meet LORA Partitions guidelines. It minimizes the number of localities used to meet the CPU and memory requirements of a
		     workload.

	      This value causes HP-UX to operate in SMP mode operation. It spreads the
		     load evenly across all the localities.

   Restrictions on Changing
       Changes to this tunable take effect upon next reboot.

   When Should the Value of This Tunable Be Changed to 1?
       should be changed to 1 if the partition is configured with more than 50% local memory but is not compliant with LORA guidelines.

   When Should the Value of This Tunable Be Changed to -1?
       should be set to -1 on NUMA server if the partition has been extensively tuned for NUMA by passing hints to APIs such as and  or  by  using
       commands such as The memory allocation policy should be appropriately set using the tunable.

WARNINGS

       All  HP-UX kernel tunable parameters are release specific.  This parameter may be removed or have its meaning changed in future releases of
       HP-UX.

       Installation of optional kernel software, from HP or other vendors, may cause changes to tunable  parameter  values.   After  installation,
       some  tunable  parameters may no longer be at the default or recommended values.  For information about the effects of installation on tun-
       able values, consult the documentation for the kernel software being installed.	For information about optional kernel  software  that  was
       factory installed on your system, see at

AUTHOR

       was developed by HP.

SEE ALSO

       mpsched(1), parconfig(1M), parcreate(1M), parmodify(1M), fadvise(2), shmget(2), mpctl(2), numa_policy(5), numa_sched_launch(5), lora(7).

       white paper at

							     Tunable Kernel Parameters						      numa_mode(5)