1CHCPU(8)                     System Administration                    CHCPU(8)
2
3
4

NAME

6       chcpu - configure CPUs
7

SYNOPSIS

9       chcpu -c|-d|-e|-g cpu-list
10
11       chcpu -p mode
12
13       chcpu -r|-h|-V
14

DESCRIPTION

16       chcpu can modify the state of CPUs. It can enable or disable CPUs, scan
17       for new CPUs, change the CPU dispatching mode of the underlying
18       hypervisor, and request CPUs from the hypervisor (configure) or return
19       CPUs to the hypervisor (deconfigure).
20
21       Some options have a cpu-list argument. Use this argument to specify a
22       comma-separated list of CPUs. The list can contain individual CPU
23       addresses or ranges of addresses. For example, 0,5,7,9-11 makes the
24       command applicable to the CPUs with the addresses 0, 5, 7, 9, 10, and
25       11.
26

OPTIONS

28       -c, --configure cpu-list
29           Configure the specified CPUs. Configuring a CPU means that the
30           hypervisor takes a CPU from the CPU pool and assigns it to the
31           virtual hardware on which your kernel runs.
32
33       -d, --disable cpu-list
34           Disable the specified CPUs. Disabling a CPU means that the kernel
35           sets it offline.
36
37       -e, --enable cpu-list
38           Enable the specified CPUs. Enabling a CPU means that the kernel
39           sets it online. A CPU must be configured, see -c, before it can be
40           enabled.
41
42       -g, --deconfigure cpu-list
43           Deconfigure the specified CPUs. Deconfiguring a CPU means that the
44           hypervisor removes the CPU from the virtual hardware on which the
45           Linux instance runs and returns it to the CPU pool. A CPU must be
46           offline, see -d, before it can be deconfigured.
47
48       -p, --dispatch mode
49           Set the CPU dispatching mode (polarization). This option has an
50           effect only if your hardware architecture and hypervisor support
51           CPU polarization. Available modes are:
52
53           horizontal
54               The workload is spread across all available CPUs.
55
56           vertical
57               The workload is concentrated on few CPUs.
58
59       -r, --rescan
60           Trigger a rescan of CPUs. After a rescan, the Linux kernel
61           recognizes the new CPUs. Use this option on systems that do not
62           automatically detect newly attached CPUs.
63
64       -h, --help
65           Display help text and exit.
66
67       -V, --version
68           Print version and exit.
69

EXIT STATUS

71       chcpu has the following exit status values:
72
73       0
74           success
75
76       1
77           failure
78
79       64
80           partial success
81

AUTHORS

83       Heiko Carstens <heiko.carstens@de.ibm.com>
84

86       Copyright IBM Corp. 2011
87

SEE ALSO

89       lscpu(1)
90

REPORTING BUGS

92       For bug reports, use the issue tracker at
93       https://github.com/util-linux/util-linux/issues.
94

AVAILABILITY

96       The chcpu command is part of the util-linux package which can be
97       downloaded from Linux Kernel Archive
98       <https://www.kernel.org/pub/linux/utils/util-linux/>.
99
100
101
102util-linux 2.38.1                 2022-05-11                          CHCPU(8)
Impressum