LSTOPO(1) hwloc LSTOPO(1)NAME
lstopo, lstopo-no-graphics - Show the topology of the system (note that
hwloc-bind(1) provides a detailed explanation of the hwloc system; it
should be read before reading this man page).
SYNOPSIS
lstopo [ options ]... [ filename ]
lstopo-no-graphics [ options ]... [ filename ]
OPTIONS--of <format>, --output-format <format>
Enforce the output in the given format. See the OUTPUT FORMATS
section below.
-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.
-v --verbose
Include additional detail.
-s --silent
Reduce the amount of details to show.
-l --logical
Display hwloc logical indexes instead of physical/OS indexes
(default for console output). These indexes are prefixed with
"L#". The physical indexes of some objects (PU and Node by
default, all objects if verbose) will appear as object attribute
"P#...".
-p --physical
Display OS/physical indexes instead of hwloc logical indexes
(default for graphical output). These indexes are prefixed with
"P#" instead of "L#" in the console output.
-c --cpuset
Display the cpuset of each object.
-C --cpuset-only
Only display the cpuset of each object; do not display anything
else about the object.
--taskset
Show CPU set strings in the format recognized by the taskset
command-line program instead of hwloc-specific CPU set string
format. This option should be combined with --cpuset or
--cpuset-only, otherwise it will imply --cpuset.
--only <type>
Only show objects of the given type in the textual output.
--ignore <type>
Ignore all objects of type <type> in the topology.
--no-caches
Do not show caches.
--no-useless-caches
Do not show caches which do not have a hierarchical impact.
--no-icaches
Do not show Instruction caches, only Data and Unified caches are
displayed.
--whole-system
Do not consider administration limitations.
--merge
Do not show levels that do not have a hierarchical impact.
--restrict <cpuset>
Restrict the topology to the given cpuset.
--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_THISSYS‐
TEM set to 1 in the environment).
--no-io
Do not show any I/O device or bridge. By default, common
devices (GPUs, NICs, block devices, ...) and interesting bridges
are shown.
--no-bridges
Do not show any I/O bridge except hostbridges. By default, com‐
mon devices (GPUs, NICs, block devices, ...) and interesting
bridges are shown.
--whole-io
Show all I/O devices and bridges. 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 in the graphical output (in Green, see the
COLORS section below). If 0 is given as pid, the current bind‐
ing for the lstopo process will be shown.
--ps --top
Show existing processes as misc objects in the output. To avoid
uselessly cluttering the output, only processes that are
restricted to some part of the machine are shown. On Linux,
kernel threads are not shown. If many processes appear, the
output may become hard to read anyway, making the hwloc-ps pro‐
gram more practical.
--fontsize <size>
Set size of text font.
--gridsize <size>
Set size of margin between elements.
--horiz, --horiz=<type1,...>
Horizontal graphical layout instead of nearly 4/3 ratio. If a
comma-separated list of types is given, the layout only applies
to the corresponding containers.
--vert, --vert=<type1,...>
Vertical graphical layout instead of nearly 4/3 ratio. If a
comma-separated list of types is given, the layout only applies
to the corresponding containers.
--no-legend
Remove the text legend at the bottom.
--version
Report version and exit.
DESCRIPTION
lstopo and lstopo-no-graphics are capable of displaying a topological
map of the system in a variety of different output formats. The only
difference between lstopo and lstopo-no-graphics is that graphical out‐
puts are only supported by lstopo, to reduce dependencies on external
libraries.
If no filename is specified and the DISPLAY environment variable is
set, lstopo displays the map in a graphical window. If no filename is
specified and the DISPLAY environment variable is not set, a text sum‐
mary is displayed.
The filename specified directly implies the output format that will be
used; see the OUTPUT FORMATS section, below. Output formats that sup‐
port color will indicate specific characteristics about individual CPUs
by their color; see the COLORS section, below.
OUTPUT FORMATS
The filename on the command line usually determines the format of the
output. There are a few filenames that indicate specific output for‐
mats and devices (e.g., a filename of "-" will output a text summary to
stdout), but most filenames indicate the desired output format by their
suffix (e.g., "topo.png" will output a PNG-format file).
The format of the output may also be changed with "--of". For
instance, "--of pdf" will generate a PDF-format file on the standard
output, while "--of fig toto" will output a Xfig-format file named
"toto".
The list of currently supported formats is given below. Any of them may
be used with "--of" or as a filename suffix.
default
Send the output to a window or to the console depending on the
environment.
console
Send a text summary to stdout. No color annotation for binding,
unallowed or offline processors is shown in this mode; see the
COLORS section, below.
txt Output an ASCII art representation of the map. If outputting to
stdout and if colors are supported on the terminal, the output
will be colorized.
fig Output a representation of the map that can be loaded in Xfig.
pdf If lstopo was compiled with the proper support, lstopo outputs a
PDF representation of the map.
ps If lstopo was compiled with the proper support, lstopo outputs a
Postscript representation of the map.
png If lstopo was compiled with the proper support, lstopo outputs a
PNG representation of the map.
svg If lstopo was compiled with the proper support, lstopo outputs
an SVG representation of the map.
synthetic
If the topology is symmetric, lstopo outputs a synthetic
description string. This output may be reused as an input syn‐
thetic topology description later.
xml If lstopo was compiled with the proper support, lstopo outputs
an XML representation of the map. It may be reused later, even
on another machine, with lstopo --input, the HWLOC_XMLFILE envi‐
ronment variable, or the hwloc_topology_set_xml() function.
The following special names may be used:
- Send a text summary to stdout.
/dev/stdout
Send a text summary to stdout. It is effectively the same as
specifying "-".
-.<format>
If the entire filename is "-.<format>", lstopo behaves as if
"--of <format> -" was given, which means a file of the given
format is sent to the standard output.
See the output of "lstopo --help" for a specific list of what graphical
output formats are supported in your hwloc installation.
COLORS
Individual CPUs are colored in the semi-graphical and graphical output
formats to indicate different characteristics:
Green The topology is reported as seen by a specific process (see
--pid), and the given CPU is in this process CPU binding mask.
White The CPU is in the allowed set (see below). If the topology is
reported as seen by a specific process (see --pid), the given
CPU is also not in this process CPU binding mask.
Red The CPU is not in the allowed set (see below).
Black The CPU is offline (not all OS's support displaying offline
CPUs).
The "allowed set" is the set of CPUs to which the current process is
allowed to bind. The allowed set is usually either inherited from the
parent process or set by administrative qpolicies on the system. Linux
cpusets are one example of limiting the allowed set for a process and
its children to be less than the full set of CPUs on the system.
Different processes may therefore have different CPUs in the allowed
set. Hence, invoking lstopo in different contexts and/or as different
users may display different colors for the same individual CPUs (e.g.,
running lstopo in one context may show a specific CPU as red, but run‐
ning lstopo in a different context may show the same CPU as white).
Some lstopo output modes, e.g. the console mode (default non-graphical
output), do not support colors at all. The above characteristics are
not shown in this case.
LAYOUT
In its graphical output, lstopo uses simple rectangular heuristics to
try to achieve a 4/3 ratio between width and height. However, in the
particular case of NUMA nodes, the layout is always a flat rectangle,
to avoid letting the user believe any particular NUMA topology (lstopo
is not able to render that yet).
EXAMPLES
To display the machine topology in textual mode:
lstopo-no-graphics
To display the machine topology in pseudo-graphical mode:
lstopo-no-graphics -.txt
To display in graphical mode (assuming that the DISPLAY environment
variable is set to a relevant value):
lstopo
To export the topology to a PNG file:
lstopo file.png
To export an XML file on a machine and later display the corresponding
graphical output on another machine:
machine1$ lstopo file.xml
<transfer file.xml from machine1 to machine2>
machine2$ lstopo --input file.xml
To save the current machine topology to XML and later reload it faster
while still considering it as the current machine:
$ lstopo file.xml
<...>
$ lstopo --input file.xml --thissystem
To restrict an XML topology to only physical processors 0, 1, 4 and 5:
lstopo --input file.xml --restrict 0x33 newfile.xml
To restrict an XML topology to only numa node whose logical index is 1:
lstopo --input file.xml --restrict $(hwloc-calc --input file.xml
node:1) newfile.xml
To display a summary of the topology:
lstopo -s
To get more details about the topology:
lstopo -v
To only show cores:
lstopo --only core
To show cpusets:
lstopo --cpuset
To only show the cpusets of sockets:
lstopo --only socket --cpuset-only
Simulate a fake hierarchy; this example shows with 2 NUMA nodes of 2
processor units:
lstopo --input "n:2 2"
To count the number of logical processors in the system
lstopo --only pu | wc -l
SEE ALSOhwloc-bind(1), hwloc-ps(1), hwloc-gather-topology(1)1.5 Jul 30, 2012 LSTOPO(1)
