1LSCPU(1)                         User Commands                        LSCPU(1)
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NAME

6       lscpu - display information about the CPU architecture
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SYNOPSIS

9       lscpu [options]
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DESCRIPTION

12       lscpu  gathers  CPU  architecture information from sysfs, /proc/cpuinfo
13       and any applicable architecture-specific  libraries  (e.g.  librtas  on
14       Powerpc).   The command output can be optimized for parsing or for easy
15       readability by humans.  The information includes, for example, the num‐
16       ber  of  CPUs,  threads,  cores, sockets, and Non-Uniform Memory Access
17       (NUMA) nodes.  There is also information about the CPU caches and cache
18       sharing, family, model, bogoMIPS, byte order, and stepping.
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20       In virtualized environments, the CPU architecture information displayed
21       reflects the configuration of the guest operating system which is typi‐
22       cally different from the physical (host) system.  On architectures that
23       support retrieving physical topology information, lscpu  also  displays
24       the number of physical sockets, chips, cores in the host system.
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26       Options  that result in an output table have a list argument.  Use this
27       argument to customize the command output.   Specify  a  comma-separated
28       list  of  column labels to limit the output table to only the specified
29       columns, arranged in the specified order.  See COLUMNS for  a  list  of
30       valid column labels.  The column labels are not case sensitive.
31
32       Not  all columns are supported on all architectures.  If an unsupported
33       column is specified, lscpu prints the column but does not  provide  any
34       data for it.
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36       The  default  output  formatting on terminal maybe optimized for better
37       readability.  The output  for  non-terminals  (e.g.,  pipes)  is  never
38       affected  by this optimization and it is always in "Field: data\n" for‐
39       mat.
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41       The cache sizes are reported as summary from all  CPUs.   The  versions
42       before v2.34 reported per-core sizes, but this output was confusing due
43       to complicated CPUs topology and the way how caches are shared  between
44       CPUs. For more details about caches see --cache.
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46   COLUMNS
47       Note  that  topology  elements  (core,  socket,  etc.) use a sequential
48       unique ID starting from zero, but CPU logical numbers follow the kernel
49       where there is no guarantee of sequential numbering.
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51       CPU    The logical CPU number of a CPU as used by the Linux kernel.
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53       CORE   The logical core number.  A core can contain several CPUs.
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55       SOCKET The logical socket number.  A socket can contain several cores.
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57       BOOK   The logical book number.  A book can contain several sockets.
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59       DRAWER The logical drawer number.  A drawer can contain several books.
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61       NODE   The  logical NUMA node number.  A node can contain several draw‐
62              ers.
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64       CACHE  Information about how caches are shared between CPUs.
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66       ADDRESS
67              The physical address of a CPU.
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69       ONLINE Indicator that shows whether the Linux instance currently  makes
70              use of the CPU.
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72       CONFIGURED
73              Indicator  that shows if the hypervisor has allocated the CPU to
74              the virtual hardware on which the  Linux  instance  runs.   CPUs
75              that  are  configured  can  be set online by the Linux instance.
76              This column contains data  only  if  your  hardware  system  and
77              hypervisor support dynamic CPU resource allocation.
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79       POLARIZATION
80              This  column  contains data for Linux instances that run on vir‐
81              tual hardware with a hypervisor that can  switch  the  CPU  dis‐
82              patching mode (polarization).  The polarization can be:
83
84              horizontal  The workload is spread across all available CPUs.
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86              vertical    The workload is concentrated on few CPUs.
87
88              For  vertical  polarization, the column also shows the degree of
89              concentration, high, medium, or low.  This column contains  data
90              only  if  your hardware system and hypervisor support CPU polar‐
91              ization.
92
93       MAXMHZ Maximum megahertz value for the CPU. Useful when lscpu  is  used
94              as  hardware  inventory information gathering tool.  Notice that
95              the megahertz value is  dynamic,  and  driven  by  CPU  governor
96              depending on current resource need.
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98       MINMHZ Minimum megahertz value for the CPU.
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OPTIONS

101       -a, --all
102              Include lines for online and offline CPUs in the output (default
103              for -e).  This option may only be specified together with option
104              -e or -p.
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106       -B, --bytes
107              Print the sizes in bytes rather than in a human-readable format.
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109       -b, --online
110              Limit  the  output to online CPUs (default for -p).  This option
111              may only be specified together with option -e or -p.
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113       -C, --caches[=list]
114              Display details about CPU caches.  For details  about  available
115              information see --help output.
116
117              If  the  list argument is omitted, all columns for which data is
118              available are included in the command output.
119
120              When specifying the list argument, the string of  option,  equal
121              sign  (=),  and list must not contain any blanks or other white‐
122              space.   Examples:  '-C=NAME,ONE-SIZE'  or   '--caches=NAME,ONE-
123              SIZE'.
124
125       -c, --offline
126              Limit the output to offline CPUs.  This option may only be spec‐
127              ified together with option -e or -p.
128
129       -e, --extended[=list]
130              Display the CPU information in human-readable format.
131
132              If the list argument is omitted, all columns for which  data  is
133              available are included in the command output.
134
135              When  specifying  the list argument, the string of option, equal
136              sign (=), and list must not contain any blanks or  other  white‐
137              space.  Examples: '-e=cpu,node' or '--extended=cpu,node'.
138
139       -h, --help
140              Display help text and exit.
141
142       -J, --json
143              Use  JSON output format for the default summary or extended out‐
144              put (see --extended).
145
146       -p, --parse[=list]
147              Optimize the command output for easy parsing.
148
149              If the list argument is omitted, the command output is  compati‐
150              ble  with earlier versions of lscpu.  In this compatible format,
151              two commas are used to separate CPU cache columns.   If  no  CPU
152              caches are identified the cache column is omitted.
153              If the list argument is used, cache columns are separated with a
154              colon (:).
155
156              When specifying the list argument, the string of  option,  equal
157              sign  (=),  and list must not contain any blanks or other white‐
158              space.  Examples: '-p=cpu,node' or '--parse=cpu,node'.
159
160       -s, --sysroot directory
161              Gather CPU data for a Linux instance  other  than  the  instance
162              from which the lscpu command is issued.  The specified directory
163              is the system root of the Linux instance to be inspected.
164
165       -x, --hex
166              Use hexadecimal masks for CPU  sets  (for  example  "ff").   The
167              default  is  to print the sets in list format (for example 0,1).
168              Note that before version 2.30 the mask has been printed with  0x
169              prefix.
170
171       -y, --physical
172              Display  physical  IDs  for  all  columns with topology elements
173              (core,  socket,  etc.).   Other  than  logical  IDs,  which  are
174              assigned  by  lscpu,  physical  IDs are platform-specific values
175              that are provided by the kernel. Physical IDs are not  necessar‐
176              ily  unique and they might not be arranged sequentially.  If the
177              kernel could not retrieve a physical ID  for  an  element  lscpu
178              prints the dash (-) character.
179
180              The CPU logical numbers are not affected by this option.
181
182       -V, --version
183              Display version information and exit.
184
185       --output-all
186              Output all available columns.  This option must be combined with
187              either --extended, --parse or --caches.
188

BUGS

190       The basic overview of CPU family, model, etc. is always  based  on  the
191       first CPU only.
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193       Sometimes in Xen Dom0 the kernel reports wrong data.
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195       On virtual hardware the number of cores per socket, etc. can be wrong.
196

AUTHOR

198       Cai Qian <qcai@redhat.com>
199       Karel Zak <kzak@redhat.com>
200       Heiko Carstens <heiko.carstens@de.ibm.com>
201

SEE ALSO

203       chcpu(8)
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AVAILABILITY

206       The  lscpu  command  is part of the util-linux package and is available
207       from https://www.kernel.org/pub/linux/utils/util-linux/.
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211util-linux                        March 2019                          LSCPU(1)
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