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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 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.

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, --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 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 information and exit.

       -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 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 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 ftp://ftp.kernel.org/pub/linux/utils/util-linux/.



util-linux			 January 2013			      LSCPU(1)