info > CHCPU

man perldoc info pydoc3 ri search

🏷️ NAME

chcpu — configure CPUs

🚀 Quick Reference

Use Case	Command	Description
Configure CPUs	chcpu -c cpu-list	Assign CPUs from hypervisor pool to virtual hardware
Disable CPUs	chcpu -d cpu-list	Set CPUs offline
Enable CPUs	chcpu -e cpu-list	Set CPUs online (must be configured first)
Deconfigure CPUs	chcpu -g cpu-list	Return CPUs to hypervisor pool (must be offline first)
Set dispatch mode	chcpu -p mode	Change CPU polarization (horizontal/vertical)
Rescan CPUs	chcpu -r	Detect newly attached CPUs
Show help	chcpu -h	Display help text and exit
Show version	chcpu -V	Display version information and exit

📋 SYNOPSIS

chcpu -c|-d|-e|-g cpu-list
chcpu -p mode
chcpu -r|-h|-V

📖 DESCRIPTION

chcpu can modify the state of CPUs. It can enable or disable CPUs, scan for new CPUs, change the CPU dispatching mode of the underlying hypervisor, and request CPUs from the hypervisor (configure) or return CPUs to the hypervisor (deconfigure).

Some options have a cpu-list argument. Use this argument to specify a comma-separated list of CPUs. The list can contain individual CPU addresses or ranges of addresses. For example, 0,5,7,9-11 makes the command applicable to the CPUs with the addresses 0, 5, 7, 9, 10, and 11.

⚙️ OPTIONS

• -c, --configure cpu-list — Configure the specified CPUs. Configuring a CPU means that the hypervisor takes a CPU from the CPU pool and assigns it to the virtual hardware on which your kernel runs.
• -d, --disable cpu-list — Disable the specified CPUs. Disabling a CPU means that the kernel sets it offline.
• -e, --enable cpu-list — Enable the specified CPUs. Enabling a CPU means that the kernel sets it online. A CPU must be configured, see -c, before it can be enabled.
• -g, --deconfigure cpu-list — Deconfigure the specified CPUs. Deconfiguring a CPU means that the hypervisor removes the CPU from the virtual hardware on which the Linux instance runs and returns it to the CPU pool. A CPU must be offline, see -d, before it can be deconfigured.
• -p, --dispatch mode — Set the CPU dispatching mode (polarization). This option has an effect only if your hardware architecture and hypervisor support CPU polarization. Available modes are:
  • horizontal — The workload is spread across all available CPUs.
  • vertical — The workload is concentrated on few CPUs.
• -r, --rescan — Trigger a rescan of CPUs. After a rescan, the Linux kernel recognizes the new CPUs. Use this option on systems that do not automatically detect newly attached CPUs.
• -V, --version — Display version information and exit.
• -h, --help — Display help text and exit.

🚪 Exit Status

• 0 — success
• 1 — failure
• 64 — partial success

👤 AUTHORS

Heiko Carstens <heiko.carstens AT de.com>

©️ COPYRIGHT

Copyright IBM Corp. 2011

🔗 SEE ALSO

lscpu(1)

🐛 REPORTING BUGS

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

📦 AVAILABILITY

The chcpu command is part of the util-linux package which can be downloaded from Linux Kernel Archive <https://www.kernel.org/pub/linux/utils/util-linux/>.

🏷️ NAME 🚀 Quick Reference 📋 SYNOPSIS 📖 DESCRIPTION ⚙️ OPTIONS 🚪 Exit Status 👤 AUTHORS ©️ COPYRIGHT 🔗 SEE ALSO 🐛 REPORTING BUGS 📦 AVAILABILITY