CoreFreq

What CoreFreq is

CoreFreq is CPU monitoring software for Linux that combines a kernel module with a user-space daemon and command-line client. It reads processor frequencies and ratios, performance counters, instructions per cycle, C-states, temperature, and documented core-voltage readings. Its display identifies processor features, brand, and architecture, and maps the processor topology, including caches. The driver also exposes controls for Turbo Boost, power management, thermal limits, prefetchers, and hardware-controlled performance states. Monitoring views and JSON-encoded system information are available through its command-line client. The README lists Intel and AMD processor families, Arm A64, RISC-V RV64, and PowerPC64 LE among supported architectures. CoreFreq is free, available for Linux and self-hosted use, and licensed under GPL-2.0. It requires Linux kernel 3.3 or newer and GNU C Library. Users can build it from source or choose distribution options for ArchLinux, Gentoo, Debian, Ubuntu, TUXEDO, Fedora, AlmaLinux, and Rocky Linux. The project says shared memory is used to protect the kernel from the user-space component. Some virtual machines may not expose registers the driver needs; enabled kernel module signature verification requires users to sign the driver. Its interface renders best in an ASCII console or VT100-capable Xterm, and may stall in terminals under 80 columns.

Who it suits

CoreFreq suits Linux users who need detailed CPU readings and want access to processor controls across supported 64-bit architectures. It is also a fit for users comfortable building from source or installing through a listed Linux distribution option.

Limits

CoreFreq is free. Some virtual machines do not provide access to registers used by the driver, and the display can stall in terminals narrower than 80 columns.

Getting started

1. Visit https://www.cyring.fr/.
2. Build CoreFreq from source or use an option for your Linux distribution.
3. Meet the Linux kernel 3.3 or newer and GNU C Library requirements.
4. Sign the driver if kernel module signature verification is enabled.
5. Use its daemon and command-line client in an ASCII console or VT100-capable Xterm.

Verdict

Choose CoreFreq if you use Linux and want processor monitoring alongside controls for supported CPU settings. Its free, multi-architecture support is useful, while virtual machines without register access and narrow terminals can limit its use.