hwloc-info(1) hwloc hwloc-info(1)
NAME
hwloc-info - Show some information about some objects or about a topology
or about support features
SYNOPSIS
hwloc-info [ options ]... <object>...
hwloc-info [ options ]...
Note that hwloc(7) provides a detailed explanation of the hwloc system
and of valid <object> formats; it should be read before reading this man
page.
OPTIONS
--objects
Report information specific objects. This is the default if some
objects are given on the command-line.
--topology
Report a summary of the topology instead of about some specific
objects. This is the default if no object is given on the
command-line.
--support
Report the features that are supported by hwloc on the topology.
The features are those available through the
hwloc_topology_get_support() function. This is useful for
verifying which CPU or memory binding options are supported by the
current hwloc installation.
-i <path>, --input <path>
Read the topology from <path> instead of discovering the topology
of the local machine.
If <path> is a file and XML support has been compiled in hwloc, it
may be a XML file exported by a previous hwloc program. If <path>
is "-", the standard input may be used as a XML file.
On Linux, <path> may be a directory containing the topology files
gathered from another machine topology with hwloc-gather-topology.
On x86, <path> may be a directory containing a cpuid dump gathered
with hwloc-gather-cpuid.
When the archivemount program is available, <path> may also be a
tarball containing such Linux or x86 topology files.
-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, cpuid
and synthetic.
-v --verbose
Include additional detail.
-s --silent
Reduce the amount of details to show. A single summary line per
object is displayed.
--ancestors
Display information about the object as well as about all its
ancestors up to the root of the topology.
--ancestor <type>
Only display the object ancestors that match the given type.
--children
Display information about the object children.
--descendants <type>
Display information about the object descendants that match the
given type.
--local-memory
Display information about the NUMA nodes that are local to the
given object.
--local-memory-flags
Change the flags used to select local NUMA nodes. Flags may be
given as numeric values or as a comma-separated list of flag names
that are passed to hwloc_get_local_numanode_objs(). Those names
may be substrings of actual flag names as long as a single one
matches. The default is 3 (or smaller,larger) which means NUMA
nodes are displayed if their locality either contains or is
contained in the locality of the given object.
This option enables --local-memory.
--best-memattr <name>
Enable the listing local memory nodes with --local-memory, but
only display the local node that has the best value for the memory
attribute given by <name> (or as an index). If the memory
attribute values depend on the initiator, the object given to
hwloc-info is used as the initiator.
-n When outputting object information, prefix each line with the
index of the considered object within the input. For instance, if
three cores were given in input, the output lines will be prefixed
with "0: ", "1: " or "2: ". If --ancestor is also used, the
prefix will be "X.Y: " where X is the index of the considered
object within the input, and Y is the parent index (0 for the
object itself, increasing towards the root of the topology).
--disallowed
Include objects disallowed by administrative limitations.
--restrict <cpuset>
Restrict the topology to the given cpuset.
--restrict nodeset=<nodeset>
Restrict the topology to the given nodeset, unless
--restrict-flags specifies something different.
--restrict binding
Restrict the topology to the current process binding. This option
requires the use of the actual current machine topology (or any
other topology with --thissystem or with HWLOC_THISSYSTEM set to 1
in the environment).
--restrict-flags <flags>
Enforce flags when restricting the topology. Flags may be given
as numeric values or as a comma-separated list of flag names that
are passed to hwloc_topology_restrict(). Those names may be
substrings of actual flag names as long as a single one matches,
for instance bynodeset,memless. The default is 0 (or none).
--filter <type>:<kind>, --filter <type>
Filter objects of type <type>, or of any type if <type> is "all".
"io", "cache" and "icache" are also supported.
<kind> specifies the filtering behavior. If "none" or not
specified, all objects of the given type are removed. If "all",
all objects are kept as usual. If "structure", objects are kept
when they bring structure to the topology. If "important" (only
applicable to I/O and Misc), only important objects are kept. See
hwloc_topology_set_type_filter() for more details.
--no-icaches
Do not show Instruction caches, only Data and Unified caches are
considered. This is identical to --filter icache:none.
--no-io
Do not show any I/O device or bridge. This is identical to
--filter io:none. By default, common devices (GPUs, NICs, block
devices, ...) and interesting bridges are shown.
--no-bridges
Do not show any I/O bridge except hostbridges. This is identical
to --filter bridge:none. By default, common devices (GPUs, NICs,
block devices, ...) and interesting bridges are shown.
--whole-io
Show all I/O devices and bridges. This is identical to --filter
io:all. By default, only common devices (GPUs, NICs, block
devices, ...) and interesting bridges are shown.
--thissystem
Assume that the selected backend provides the topology for the
system on which we are running. This is useful when using
--restrict binding and loading a custom topology such as an XML
file.
--pid <pid>
Detect topology as seen by process <pid>, i.e. as if process <pid>
did the discovery itself. Note that this can for instance change
the set of allowed processors. Also show this process current CPU
binding by marking the corresponding PUs (in Green in the
graphical output, see the COLORS section below, or by appending
(binding) to the verbose text output). If 0 is given as pid, the
current binding for the lstopo process will be shown.
-p --physical
Use OS/physical indexes instead of logical indexes for input.
-l --logical
Use logical indexes instead of physical/OS indexes for input
(default).
--version
Report version and exit.
-h --help
Display help message and exit.
DESCRIPTION
hwloc-info displays information about the specified object. It is
intended to be used with tools such as grep for filtering certain
attribute lines. When no object is specified, or when --topology is
passed, hwloc-info prints a summary of the topology. When --support is
passed, hwloc-info lists the supported features for the topology.
Objects may be specified as location tuples, as explained in hwloc(7).
However hexadecimal bitmasks are not accepted since they may correspond
to multiple objects.
NOTE: It is highly recommended that you read the hwloc(7) overview page
before reading this man page. Most of the concepts described in hwloc(7)
directly apply to the hwloc-calc utility.
EXAMPLES
To display information about each package:
$ hwloc-info package:all
Package L#0
logical index = 0
...
To display information about the core whose physical index is 2:
$ hwloc-info -p core:2
Core L#1
logical index = 1
os index = 2
...
To list the NUMA nodes that are local a PU:
$ hwloc-info --local-memory pu:25
NUMANode L#6 = local memory #0 of PU L#25
type = NUMANode
...
NUMANode L#7 = local memory #1 of PU L#25
type = NUMANode
...
To show the best-bandwidth node among NUMA nodes local to a PU:
$ hwloc-info --local-memory --best-memattr bandwidth pu:25
NUMANode L#7 = local memory #1 of PU L#25
type = NUMANode
...
SEE ALSO
hwloc(7), lstopo(1), hwloc-calc(1), hwloc-bind(1), hwloc-ps(1)
2.8.0 June 29, 2022 hwloc-info(1)
hwloc 2.8.0 - Generated Sun Aug 28 14:39:20 CDT 2022