hwloc-distances(1) [centos man page]

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

NAME

       hwloc-distances - Displays distance matrices

SYNOPSIS

       hwloc-distances [options]

OPTIONS

       -l --logical
	      Display hwloc logical indexes (default) instead of physical/OS indexes.

       -p --physical
	      Display OS/physical indexes instead of hwloc logical indexes.

       -i <file>, --input <file>
	      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.

       -i <directory>, --input <directory>
	      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.

       -i <specification>, --input <specification>
	      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.

       --if <format>, --input-format <format>
	      Enforce the input in the given format, among xml, fsroot and synthetic.

       --restrict <cpuset>
	      Restrict the topology to the given cpuset.

       -v --verbose
	      Verbose messages.

       --version
	      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)

1.7								   Apr 07, 2013 						HWLOC-DISTANCES(1)

HWLOC-GATHER-TOPOLOGY(1)					       hwloc						  HWLOC-GATHER-TOPOLOGY(1)

NAME

       hwloc-gather-topology - Saves the relevant Linux topology files and the lstopo output for later (possibly offline) usage

SYNOPSIS

       hwloc-gather-topology [options] <path>

OPTIONS

       -h --help display help message and exit

DESCRIPTION

       hwloc-gather-topology  saves  all  the relevant topology files into an archive (<path>.tar.bz2) and the lstopo output (<path>.output).  The
       utility for example stores the /proc/cpuinfo file and the entire /sys/devices/system/node/ directory tree.

       These files can be used later to explore the machine topology offline.  Once the tarball has been extracted, it may for instance  be  given
       to  some  hwloc	command-line  utilities through their --input option.  It is also possible to override the default topology that the hwloc
       library will read by setting the extracted path in the HWLOC_FSROOT environment variable.

       Both archive and lstopo output may also be submitted to hwloc developers to debug issues remotely.

       hwloc-gather-topology is a Linux specific tool, it is not installed on other operating systems.

       NOTE: It is highly recommended that you read the hwloc(7) overview page before reading this man page.

EXAMPLES

       To store topology information to be used later (possibly on a different host) please run:

	    hwloc-gather-topology /tmp/myhost

       It will store all relevant topology files in the /tmp/myhost.tar.bz2 archive and the lstopo output in the /tmp/myhost.output  file.   These
       files can be transferred on another host for later/offline analysis and/or as the input to various hwloc utilities.

       To use these data with hwloc utilities you have to unpack myhost.tar.bz2 archive first:

	    tar jxvf /tmp/myhost.tar.bz2

       A new directory named myhost now contains all topology files.  Then you ask various hwloc utilities to use this topology instead of the one
       of the real machine by passing --input myhost.  To display the topology just run:

	    lstopo --input ./myhost

       It is not necessary that the topology is extracted in the current directory, absolute or relative paths are also supported:

	    lstopo --input /path/to/remote/host/extracted/topology/

       To see how hwloc would distribute 8 parallel jobs on the original host:

	    hwloc-distrib --input myhost --single 8

       To get the corresponding physical indexes in the previous command:

	    hwloc-calc --input myhost --po --li --proclist $(hwloc-distrib --input myhost --single 8)

       Any program may actually override the default topology with a given archived  one  even	if  it	does  not  have  a  --input  option.   The
       HWLOC_FSROOT environment variable should be used to do so:

	    HWLOC_FSROOT=myhost hwloc-calc --po --li --proclist $(hwloc-distrib --single 8)

       All  these commands will produce the same output as if executed directly on the host on which the topology information was originally gath-
       ered by the hwloc-gather-topology script.

RETURN VALUE

       Upon successful execution, hwloc-gather-topology will exit with the code 0.

       hwloc-gather-topology will return nonzero exit status if any kind of error occurs, such as (but not limited to) failure to create  the  ar-
       chive or output file.

SEE ALSO

       hwloc(7), lstopo(1), hwloc-calc(1), hwloc-distrib(1)

1.7								   Apr 07, 2013 					  HWLOC-GATHER-TOPOLOGY(1)