Write power measurements to a CSV file. A header line is written once, then one row per second is appended.
-o, --overwrite
When used with -f, overwrite the file on each write instead of appending. Only the latest measurement is kept in the file. Useful when another program is polling the file.
-i, --numeric
Print only a bare numeric value (watts, two decimal places) with no labels or ANSI formatting. Useful for piping or scripting. The value printed is total power by default, or the selected component if -c is set.
-s, --silent
Suppress all terminal output. CSV export, ring buffer, and API remain active. Useful when running in the background.
-r, --ringbuffer
Write power data to a shared-memory ring buffer every second. See Exporting Power Data for paths and data layout.
--api-port <PORT>
Start an HTTP and WebSocket API server on the given port. Requires the api feature. See Exporting Power Data for endpoint details.
Restrict output to a single hardware component. Use cpu for CPU-only power, gpu for GPU-only power. When set, only that component’s power is shown on the terminal and written to CSV or numeric output.
These options subtract idle CPU power before attributing energy to a process or application. This gives a more accurate picture of how much power the workload itself is consuming, rather than including the base system cost.
Option
Description
--cpu-idle-baseline <WATTS>
Subtract a fixed value (in watts) from CPU power before calculating process or application attribution.
--calibrate-cpu-idle-baseline
Automatically measure idle CPU power. Joular Core collects 5 samples at 1-second intervals before starting the main monitoring loop, averages them, and uses the result as the baseline.
--cpu-idle-baseline and --calibrate-cpu-idle-baseline are mutually exclusive.
How often (in seconds) to rescan running processes when monitoring an application by name with -a. Setting this to 0 disables caching and rescans on every second. Lower values catch short-lived processes faster at the cost of more frequent process enumeration.
Path to a JSON file containing a custom SBC power model. If unset, built-in models for supported boards are used. The file format must match the Joular Power Models Database schema.