1LSCPU(1) User Commands LSCPU(1)
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6 lscpu - display information about the CPU architecture
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9 lscpu [-a|-b|-c|-J] [-x] [-y] [-s directory] [-e[=list]|-p[=list]]
10 lscpu -h|-V
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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.
20 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.
26 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.
32 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.
36 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.
42 CPU The logical CPU number of a CPU as used by the Linux kernel.
44 CORE The logical core number. A core can contain several CPUs.
46 SOCKET The logical socket number. A socket can contain several cores.
48 BOOK The logical book number. A book can contain several sockets.
50 DRAWER The logical drawer number. A drawer can contain several books.
52 NODE The logical NUMA node number. A node can contain several draw‐
54 ers.
55 CACHE Information about how caches are shared between CPUs.
57 ADDRESS
59 The physical address of a CPU.
60 ONLINE Indicator that shows whether the Linux instance currently makes
62 use of the CPU.
63 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.
70 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:
75 horizontal The workload is spread across all available CPUs.
77 vertical The workload is concentrated on few CPUs.
79 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.
84 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.
89 MINMHZ Minimum megahertz value for the CPU.
91
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.
97 -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.
101 -c, --offline
103 Limit the output to offline CPUs. This option may only be spec‐
104 ified together with option -e or -p.
105 -e, --extended[=list]
107 Display the CPU information in human-readable format.
108 If the list argument is omitted, all columns for which data is
110 available are included in the command output.
111 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'.
115 -h, --help
117 Display help text and exit.
118 -J, --json
120 Use JSON output format for the default summary or extended out‐
121 put (see --extended).
122 -p, --parse[=list]
124 Optimize the command output for easy parsing.
125 If the list argument is omitted, the command output is compati‐
127 ble with earlier versions of lscpu. In this compatible format,
128 two commas are used to separate CPU cache columns. If no CPU
129 caches are identified the cache column is omitted.
130 If the list argument is used, cache columns are separated with a
131 colon (:).
132 When specifying the list argument, the string of option, equal
134 sign (=), and list must not contain any blanks or other white‐
135 space. Examples: '-p=cpu,node' or '--parse=cpu,node'.
136 -s, --sysroot directory
138 Gather CPU data for a Linux instance other than the instance
139 from which the lscpu command is issued. The specified directory
140 is the system root of the Linux instance to be inspected.
141 -x, --hex
143 Use hexadecimal masks for CPU sets (for example 0x3). The
144 default is to print the sets in list format (for example 0,1).
145 -y, --physical
147 Display physical IDs for all columns with topology elements
148 (core, socket, etc.). Other than logical IDs, which are
149 assigned by lscpu, physical IDs are platform-specific values
150 that are provided by the kernel. Physical IDs are not necessar‐
151 ily unique and they might not be arranged sequentially. If the
152 kernel could not retrieve a physical ID for an element lscpu
153 prints the dash (-) character.
154 The CPU logical numbers are not affected by this option.
156 -V, --version
158 Display version information and exit.
159
161 The basic overview of CPU family, model, etc. is always based on the
162 first CPU only.
163 Sometimes in Xen Dom0 the kernel reports wrong data.
165 On virtual hardware the number of cores per socket, etc. can be wrong.
167
169 Cai Qian <qcai@redhat.com>
170 Karel Zak <kzak@redhat.com>
171 Heiko Carstens <heiko.carstens@de.ibm.com>
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174 chcpu(8)
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177 The lscpu command is part of the util-linux package and is available
178 from https://www.kernel.org/pub/linux/utils/util-linux/.
179util-linux November 2015 LSCPU(1)