lscpu

LSCPU(1)                         User Commands                        LSCPU(1)

NAME
       lscpu - display information about the CPU architecture

SYNOPSIS
       lscpu [options]

DESCRIPTION
       lscpu  gathers  CPU  architecture information from sysfs, /proc/cpuinfo
       and any applicable architecture-specific  libraries  (e.g.  librtas  on
       Powerpc).   The command output can be optimized for parsing or for easy
       readability by humans.  The information includes, for example, the num-
       ber  of  CPUs,  threads,  cores, sockets, and Non-Uniform Memory Access
       (NUMA) nodes.  There is also information about the CPU caches and cache
       sharing, family, model, bogoMIPS, byte order, and stepping.

       In virtualized environments, the CPU architecture information displayed
       reflects the configuration of the guest operating system which is typi-
       cally different from the physical (host) system.  On architectures that
       support retrieving physical topology information, lscpu  also  displays
       the number of physical sockets, chips, cores in the host system.

       Options  that result in an output table have a list argument.  Use this
       argument to customize the command output.   Specify  a  comma-separated
       list  of  column labels to limit the output table to only the specified
       columns, arranged in the specified order.  See COLUMNS for  a  list  of
       valid column labels.  The column labels are not case sensitive.

       Not  all columns are supported on all architectures.  If an unsupported
       column is specified, lscpu prints the column but does not  provide  any
       data for it.

       The  default  output  formatting on terminal maybe optimized for better
       readability.  The output for non-terminals (e.g. pipes)  is  never  af-
       fected by this optimization and it is always in "Field: data\n" format.

   COLUMNS
       Note  that  topology  elements  (core,  socket,  etc.) use a sequential
       unique ID starting from zero, but CPU logical numbers follow the kernel
       where there is no guarantee of sequential numbering.

       CPU    The logical CPU number of a CPU as used by the Linux kernel.

       CORE   The logical core number.  A core can contain several CPUs.

       SOCKET The logical socket number.  A socket can contain several cores.

       BOOK   The logical book number.  A book can contain several sockets.

       DRAWER The logical drawer number.  A drawer can contain several books.

       NODE   The  logical NUMA node number.  A node can contain several draw-
              ers.

       CACHE  Information about how caches are shared between CPUs.

       ADDRESS
              The physical address of a CPU.

       ONLINE Indicator that shows whether the Linux instance currently  makes
              use of the CPU.

       CONFIGURED
              Indicator  that shows if the hypervisor has allocated the CPU to
              the virtual hardware on which the  Linux  instance  runs.   CPUs
              that  are  configured  can  be set online by the Linux instance.
              This column contains data only if your hardware system  and  hy-
              pervisor support dynamic CPU resource allocation.

       POLARIZATION
              This  column  contains data for Linux instances that run on vir-
              tual hardware with a hypervisor that can  switch  the  CPU  dis-
              patching mode (polarization).  The polarization can be:

              horizontal  The workload is spread across all available CPUs.

              vertical    The workload is concentrated on few CPUs.

              For  vertical  polarization, the column also shows the degree of
              concentration, high, medium, or low.  This column contains  data
              only  if  your hardware system and hypervisor support CPU polar-
              ization.

       MAXMHZ Maximum megahertz value for the CPU. Useful when lscpu  is  used
              as  hardware  inventory information gathering tool.  Notice that
              the megahertz value is dynamic, and driven by CPU  governor  de-
              pending on current resource need.

       MINMHZ Minimum megahertz value for the CPU.

OPTIONS
       -a, --all
              Include lines for online and offline CPUs in the output (default
              for -e).  This option may only be specified together with option
              -e or -p.

       -B, --bytes
              Print the sizes in bytes rather than in a human-readable format.

       -b, --online
              Limit  the  output to online CPUs (default for -p).  This option
              may only be specified together with option -e or -p.

       -C, --caches[=list]
              Display details about CPU caches.  For details  about  available
              information see --help output.

              If  the  list argument is omitted, all columns for which data is
              available are included in the command output.

              When specifying the list argument, the string of  option,  equal
              sign  (=),  and list must not contain any blanks or other white-
              space.   Examples:  '-C=NAME,ONE-SIZE'  or   '--caches=NAME,ONE-
              SIZE'.

       -c, --offline
              Limit the output to offline CPUs.  This option may only be spec-
              ified together with option -e or -p.

       -e, --extended[=list]
              Display the CPU information in human-readable format.

              If the list argument is omitted, all columns for which  data  is
              available are included in the command output.

              When  specifying  the list argument, the string of option, equal
              sign (=), and list must not contain any blanks or  other  white-
              space.  Examples: '-e=cpu,node' or '--extended=cpu,node'.

       -h, --help
              Display help text and exit.

       -J, --json
              Use  JSON output format for the default summary or extended out-
              put (see --extended).

       -p, --parse[=list]
              Optimize the command output for easy parsing.

              If the list argument is omitted, the command output is  compati-
              ble  with earlier versions of lscpu.  In this compatible format,
              two commas are used to separate CPU cache columns.   If  no  CPU
              caches are identified the cache column is omitted.
              If the list argument is used, cache columns are separated with a
              colon (:).

              When specifying the list argument, the string of  option,  equal
              sign  (=),  and list must not contain any blanks or other white-
              space.  Examples: '-p=cpu,node' or '--parse=cpu,node'.

       -s, --sysroot directory
              Gather CPU data for a Linux instance  other  than  the  instance
              from which the lscpu command is issued.  The specified directory
              is the system root of the Linux instance to be inspected.

       -x, --hex
              Use hexadecimal masks for CPU sets (for example "ff").  The  de-
              fault  is  to  print  the sets in list format (for example 0,1).
              Note that before version 2.30 the mask has been printed with  0x
              prefix.

       -y, --physical
              Display  physical  IDs  for  all  columns with topology elements
              (core, socket, etc.).  Other than logical  IDs,  which  are  as-
              signed  by lscpu, physical IDs are platform-specific values that
              are provided by the kernel. Physical  IDs  are  not  necessarily
              unique and they might not be arranged sequentially.  If the ker-
              nel could not retrieve a physical ID for an element lscpu prints
              the dash (-) character.

              The CPU logical numbers are not affected by this option.

       -V, --version
              Display version information and exit.

       --output-all
              Output all available columns.  This option must be combined with
              either --extended, --parse or --caches.

BUGS
       The basic overview of CPU family, model, etc. is always  based  on  the
       first CPU only.

       Sometimes in Xen Dom0 the kernel reports wrong data.

       On virtual hardware the number of cores per socket, etc. can be wrong.

AUTHOR
       Cai Qian <qcai@redhat.com>
       Karel Zak <kzak@redhat.com>
       Heiko Carstens <heiko.carstens@de.ibm.com>

SEE ALSO
       chcpu(8)

AVAILABILITY
       The  lscpu  command  is part of the util-linux package and is available
       from https://www.kernel.org/pub/linux/utils/util-linux/.

util-linux                        March 2019                          LSCPU(1)