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

       --io   Also gather I/O related files.  The gathering may be much slower, and the generated archive may be
              much bigger.  --dmi Also gather DMI/SMBIOS related files.  The gathering requires root access, and
              the dmi-sysfs kernel module should be loaded.

       -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 gathered 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 archive or output file.

SEE ALSO

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

1.11.2                                            Dec 17, 2015                          HWLOC-GATHER-TOPOLOGY(1)