i7z

Start i7z (needs to be run in superuser mode)

$ sudo i7z

i7z [-c] [-d] [-e] [-i secs] [-l] [-m] [-n count] [-p pid] [-R] [-t] [-v] [-V] [-z]

-c, --cpuinfo
    Display CPU model information only and exit

-d, --dump
    Dump statistics to CSV file (csv-i7z-*.csv)

-e, --extended
    Show extended stats like Turbo (Sandy Bridge+)

-h, --help
    Show help message

-i --interval=secs
    Refresh interval in seconds (default: 1)

-l, --load
    Display system load averages

-m, --memory
    Show memory usage statistics

-n --samples=count
    Number of samples (default: 20)

-p --pid=pid
    Monitor usage for specific process ID

-R, --rapl
    Show RAPL power data (Sandy Bridge+)

-t, --temp
    Show temperatures only

-v, --voltage
    Show core voltages

-V, --version
    Print version information

-z, --ziplock
    Show zip cores (Core 2 only)

i7z is a lightweight, command-line utility for monitoring performance metrics on Intel Core i7 processors and compatible architectures, such as Core 2 Duo/Quad, i3, i5, i7, and certain Xeons. It provides detailed per-core statistics including CPU utilization, bus clock (BCLK), multipliers, temperatures, voltages, and power draw (RAPL on newer chips).

Unlike general tools like top or htop, i7z accesses low-level Model-Specific Registers (MSRs) via the msr kernel module, delivering precise, real-time data ideal for overclockers, benchmarkers, and sysadmins troubleshooting thermal throttling or turbo boost issues.

By default, it runs interactively, refreshing every 1 second for 20 samples, displaying a scrolling table of core activity. Options allow customization: single-shot CPU info, process-specific monitoring, CSV dumps for analysis, or focused views like temperatures only. It supports extended stats on Sandy Bridge and later, including turbo ratios and C-states.

Essential for laptops and desktops under load, i7z helps identify uneven core loading or hotspots. Output is color-coded for quick visual parsing, with busier cores highlighted. While powerful, it requires root access and Intel hardware support.

Requires msr kernel module (sudo modprobe msr) and root privileges or CAP_SYS_RAWIO. Intel CPUs only; limited/no support for newest/AMD. May fail if MSR access denied. High CPU overhead during runs.

i7z -i 2 -n 5
Runs 5 samples, 2-sec intervals.

Debian/Ubuntu: sudo apt install i7z
Compile from source: github.com/phortas/i7z

Developed by Pedro A. Hortas starting 2010 as open-source tool for Core i7 monitoring. Hosted on GitHub (phortas/i7z). Major updates through 2016 adding RAPL/extended support; sporadic maintenance since.

top(1), htop(1), turbostat(8), lm-sensors(1), powertop(8), mpstat(1)