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HWLOC-DISTANCES(1) hwloc HWLOC-DISTANCES(1)

NAME

hwloc-distances - Displays distance matrices

SYNOPSIS

hwloc-distances [options]

OPTIONS

Display hwloc logical indexes (default) instead of physical/OS indexes.
Display OS/physical indexes instead of hwloc logical indexes.
Read topology from XML file <file> (instead of discovering the topology on the local machine). If <file> is "-", the standard input is used. XML support must have been compiled in to hwloc for this option to be usable.
Read topology from the chroot specified by <directory> (instead of discovering the topology on the local machine). This option is generally only available on Linux. The chroot was usually created by gathering another machine topology with hwloc-gather-topology.
Simulate a fake hierarchy (instead of discovering the topology on the local machine). If <specification> is "node:2 pu:3", the topology will contain two NUMA nodes with 3 processing units in each of them. The <specification> string must end with a number of PUs.
Enforce the input in the given format, among xml, fsroot and synthetic.
Restrict the topology to the given cpuset.
Verbose messages.
Report version and exit.

DESCRIPTION

hwloc-distances displays also distance matrices attached to the topology. A breadth-first traversal of the topology is performed starting from the root to find all distance matrices.

NOTE: lstopo may also display distance matrices in its verbose textual output. However lstopo only prints matrices that cover the entire topology while hwloc-distances also displays matrices that ignore part of the topology.

EXAMPLES

On a quad-socket opteron machine:


$ hwloc-distances
Latency matrix between 4 NUMANodes (depth 2) by logical indexes:
index 0 1 2 3
0 1.000 1.600 2.200 2.200
1 1.600 1.000 2.200 2.200
2 2.200 2.200 1.000 1.600
3 2.200 2.200 1.600 1.000

RETURN VALUE

Upon successful execution, hwloc-distances returns 0.

hwloc-distances will return nonzero if any kind of error occurs, such as (but not limited to) failure to parse the command line.

SEE ALSO

hwloc(7), lstopo(1)

July 30, 2012 1.5