Man Pages

lscpu(1) - phpMan lscpu(1) - phpMan

Command: man perldoc info search(apropos)  


LSCPU(1)                         User Commands                        LSCPU(1)



NAME
       lscpu - display information about the CPU architecture

SYNOPSIS
       lscpu [-a|-b|-c] [-x] [-s directory] [-e [=list]|-p [=list]]
       lscpu -h|-V

DESCRIPTION
       lscpu  gathers  CPU  architecture information from sysfs and /proc/cpuinfo. The command output can be optimized
       for parsing or for easy readability by humans.
       The information includes, for example, the number 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.

       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.


   COLUMNS
       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.

       NODE   The logical NUMA node number. A node may contain several books.

       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 hypervisor support dynamic CPU resource allocation.

       POLARIZATION
              This column contains data for Linux instances that run on virtual hardware with a  hypervisor  that  can
              switch the CPU dispatching 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 polarization.

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

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

       -c, --offline
              Limit the output to offline CPUs. This option may only be specified 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 information and exit.

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

              If the list argument is omitted, the command output is compatible with earlier  versions  of  lscpu.  In
              this  compatible format, two commas are used to separate CPU cache columns. If no CPU caches are identi-
              fied 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 0x3).  The default is to print the sets in  list  format
              (for example 0,1).

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

BUGS
       The basic overview about 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 <qcaiATredhat.com>
       Karel Zak <kzakATredhat.com>
       Heiko Carstens <heiko.carstensATde.com>

SEE ALSO
       chcpu(8)

AVAILABILITY
       The   lscpu   command   is   part   of   the   util-linux   package   and   is  available  from  ftp://ftp.ker-
       nel.org/pub/linux/utils/util-linux/.



util-linux                       February 2011                        LSCPU(1)