lscpu(1)

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 [-a|-b|-c|-J] [-x] [-y] [-s directory] [-e[=list]|-p[=list]]
10       lscpu -h|-V
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DESCRIPTION

13       lscpu  gathers  CPU  architecture information from sysfs, /proc/cpuinfo
14       and any applicable architecture-specific  libraries  (e.g.  librtas  on
15       Powerpc).   The command output can be optimized for parsing or for easy
16       readability by humans.  The information includes, for example, the num‐
17       ber  of  CPUs,  threads,  cores, sockets, and Non-Uniform Memory Access
18       (NUMA) nodes.  There is also information about the CPU caches and cache
19       sharing, family, model, bogoMIPS, byte order, and stepping.
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21       In virtualized environments, the CPU architecture information displayed
22       reflects the configuration of the guest operating system which is typi‐
23       cally different from the physical (host) system.  On architectures that
24       support retrieving physical topology information, lscpu  also  displays
25       the number of physical sockets, chips, cores in the host system.
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27       Options  that result in an output table have a list argument.  Use this
28       argument to customize the command output.   Specify  a  comma-separated
29       list  of  column labels to limit the output table to only the specified
30       columns, arranged in the specified order.  See COLUMNS for  a  list  of
31       valid column labels.  The column labels are not case sensitive.
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33       Not  all columns are supported on all architectures.  If an unsupported
34       column is specified, lscpu prints the column but does not  provide  any
35       data for it.
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38   COLUMNS
39       Note  that  topology  elements  (core,  socket,  etc.) use a sequential
40       unique ID starting from zero, but CPU logical numbers follow the kernel
41       where there is no guarantee of sequential numbering.
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43       CPU    The logical CPU number of a CPU as used by the Linux kernel.
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45       CORE   The logical core number.  A core can contain several CPUs.
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47       SOCKET The logical socket number.  A socket can contain several cores.
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49       BOOK   The logical book number.  A book can contain several sockets.
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51       DRAWER The logical drawer number.  A drawer can contain several books.
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53       NODE   The  logical NUMA node number.  A node can contain several draw‐
54              ers.
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56       CACHE  Information about how caches are shared between CPUs.
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58       ADDRESS
59              The physical address of a CPU.
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61       ONLINE Indicator that shows whether the Linux instance currently  makes
62              use of the CPU.
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64       CONFIGURED
65              Indicator  that shows if the hypervisor has allocated the CPU to
66              the virtual hardware on which the  Linux  instance  runs.   CPUs
67              that  are  configured  can  be set online by the Linux instance.
68              This column contains data  only  if  your  hardware  system  and
69              hypervisor support dynamic CPU resource allocation.
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71       POLARIZATION
72              This  column  contains data for Linux instances that run on vir‐
73              tual hardware with a hypervisor that can  switch  the  CPU  dis‐
74              patching mode (polarization).  The polarization can be:
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76              horizontal  The workload is spread across all available CPUs.
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78              vertical    The workload is concentrated on few CPUs.
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80              For  vertical  polarization, the column also shows the degree of
81              concentration, high, medium, or low.  This column contains  data
82              only  if  your hardware system and hypervisor support CPU polar‐
83              ization.
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85       MAXMHZ Maximum megahertz value for the CPU. Useful when lscpu  is  used
86              as  hardware  inventory information gathering tool.  Notice that
87              the megahertz value is  dynamic,  and  driven  by  CPU  governor
88              depending on current resource need.
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90       MINMHZ Minimum megahertz value for the CPU.
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OPTIONS

93       -a, --all
94              Include lines for online and offline CPUs in the output (default
95              for -e).  This option may only be specified together with option
96              -e or -p.
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98       -b, --online
99              Limit  the  output to online CPUs (default for -p).  This option
100              may only be specified together with option -e or -p.
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102       -c, --offline
103              Limit the output to offline CPUs.  This option may only be spec‐
104              ified together with option -e or -p.
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106       -e, --extended[=list]
107              Display the CPU information in human-readable format.
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109              If  the  list argument is omitted, all columns for which data is
110              available are included in the command output.
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112              When specifying the list argument, the string of  option,  equal
113              sign  (=),  and list must not contain any blanks or other white‐
114              space.  Examples: '-e=cpu,node' or '--extended=cpu,node'.
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116       -h, --help
117              Display help text and exit.
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119       -p, --parse[=list]
120              Optimize the command output for easy parsing.
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122              If the list argument is omitted, the command output is  compati‐
123              ble  with earlier versions of lscpu.  In this compatible format,
124              two commas are used to separate CPU cache columns.   If  no  CPU
125              caches are identified the cache column is omitted.
126              If the list argument is used, cache columns are separated with a
127              colon (:).
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129              When specifying the list argument, the string of  option,  equal
130              sign  (=),  and list must not contain any blanks or other white‐
131              space.  Examples: '-p=cpu,node' or '--parse=cpu,node'.
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133       -s, --sysroot directory
134              Gather CPU data for a Linux instance  other  than  the  instance
135              from which the lscpu command is issued.  The specified directory
136              is the system root of the Linux instance to be inspected.
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138       -x, --hex
139              Use hexadecimal masks for  CPU  sets  (for  example  0x3).   The
140              default is to print the sets in list format (for example 0,1).
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142       -y, --physical
143              Display  physical  IDs  for  all  columns with topology elements
144              (core,  socket,  etc.).   Other  than  logical  IDs,  which  are
145              assigned  by  lscpu,  physical  IDs are platform-specific values
146              that are provided by the kernel. Physical IDs are not  necessar‐
147              ily  unique and they might not be arranged sequentially.  If the
148              kernel could not retrieve a physical ID  for  an  element  lscpu
149              prints the dash (-) character.
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151              The CPU logical numbers are not affected by this option.
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153       -V, --version
154              Display version information and exit.
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BUGS

157       The  basic  overview  of CPU family, model, etc. is always based on the
158       first CPU only.
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160       Sometimes in Xen Dom0 the kernel reports wrong data.
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162       On virtual hardware the number of cores per socket, etc. can be wrong.
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AUTHOR

165       Cai Qian <qcai@redhat.com>
166       Karel Zak <kzak@redhat.com>
167       Heiko Carstens <heiko.carstens@de.ibm.com>
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AVAILABILITY

173       The lscpu command is part of the util-linux package  and  is  available
174       from https://www.kernel.org/pub/linux/utils/util-linux/.
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178util-linux                       November 2015                        LSCPU(1)