NAME¶

numa-preplace - A user-level program that provides NUMA placement advice

SYNOPSIS¶

numa-preplace [-w NCPUS[:MB]]

DESCRIPTION¶

numa-preplace is a program that scans NUMA topology and resource usage, and then returns information to assist management applications with initial manual binding of CPU and memory resources for their processes.

OPTIONS¶

-C <0|1>

This option controls whether or not numa-preplace treats inactive file cache as available memory. By default, numa-preplace assumes it can count inactive file cache as "free" memory when considering resources to match with processes. Specify -C 0 if numa-preplace should instead consider inactive file cache as a consumed resource. Does not apply for hugetlbfs pages.

-d

Debug output in log, sets the log level to LOG_DEBUG. Same effect as -l 7.

-h

Display usage help information and then exit.

-l <log_level>

Sets the log level to <log_level>. Reasonable choices are 5, 6, or 7. The default value is 5.

-R <CPU_LIST>

Specify a list of CPUs that numa-preplace should assume are reserved for non-numa-preplace use. No processes will be bound to the specified CPUs by numa-preplace.

-t <logical_CPU_percent>

Specify the resource value of logical CPUs. Hardware threads typically share most core resources, and so logical CPUs add only a fraction of CPU power for many workloads. By default numa-preplace considers logical CPUs to be only 20 percent of a dedicated hardware core.

-v

Verbose output in log, sets the log level to LOG_INFO. Same effect as -l 6.

-V

Display version information and exit.

-w <NCPUS[:MB]>

Queries numa-preplace for the best NUMA nodes to bind an entity that needs <NCPUS>. The amount of memory (in MBs) is optional, but should normally be specified as well <:MB> so numa-preplace can recommend NUMA nodes with available CPU capacity and adequate free memory. Output of this option is a string that contains a NUMA node list. For example: 2-3,6. The recommended node list could be saved in a shell variable (e.g., NODES) and then used as the node list parameter in a
numactl -m $NODES -N $NODES ...
command. See numactl(8).

FILES¶

/usr/sbin/numa-preplace

ENVIRONMENT VARIABLES¶

None.

EXAMPLES¶

/usr/bin/numa-preplace -w 4:4096

AUTHORS¶

Claudio Fontana <claudio.fontana@suse.com> derived from numad by Bill Gray <bgray@redhat.com>

SEE ALSO¶

numactl(8)