Command-line options

Primbench benchmarks accept command-line options that override the corresponding fields in the settings struct. When a value is set both programmatically through settings and on the command line, the command-line value takes precedence.

For details on setting values programmatically before parsing the command line, see Configure benchmark settings. For the settings struct and the rest of the benchmark API, see Primbench API.

Options reference

Option	Type / Default	Description
--help	Flag	Prints usage information and exits.
--size	size_t / 128 * MiB	Input array size in bytes. Must be greater than 0. Accepts KiB, MiB, or GiB suffixes, for example --size 256MiB.
--hot	bool / false	When set, cache clearing before kernel launches is skipped. Boolean options take no value.
--seed	uint32_t / 42	Seed used for input array generation.
--json-out	string / "results.json"	Output JSON file path.
--csv-out	string / ""	Output CSV file path. No CSV is written when empty.
--filter	string / ""	Regex filter applied to specialization names. Only matching specializations are benchmarked.
--dry	bool / false	Perform a dry run without executing kernels. Boolean options take no value.
--min-gpu-ms-per-batch	double / 10.0	Minimum GPU time in milliseconds for each batch. Must be greater than 0.
--min-secs	double / 1.0	Minimum total benchmark duration in seconds. Must be greater than 0. Must be less than or equal to --noise-timeout-secs.
--noise-timeout-secs	double / 10.0	Maximum duration in seconds before a noisy benchmark times out. Must be greater than 0.
--batch-window-size	size_t / 10	Number of recent batches used in the noise-reduction sliding window. Must be greater than 0.
--noise-tolerance-percent	double / 1.0	Noise tolerance percentage for early stopping. Must be greater than 0. Batching continues until the measurement noise falls below this threshold or the noise timeout is reached.
--min-gpu-temp	uint16_t / 50	Minimum GPU temperature in degrees Celsius. Must be less than or equal to --max-gpu-temp. If the GPU is below this temperature, Primbench runs warmup workloads until it reaches this threshold before starting a specialization.
--max-gpu-temp	uint16_t / 60	Maximum GPU temperature in degrees Celsius. If the GPU exceeds this temperature, Primbench waits for it to cool below this threshold before starting a specialization.
--max-warming-secs	double / 60.0	Maximum time in seconds to spend warming the GPU. Must be greater than 0.
--max-cooling-secs	double / 60.0	Maximum time in seconds to spend cooling the GPU. Must be greater than 0.
--output-batches	bool / false	When set, per-batch details are included in the output. Boolean options take no value.
--spaces-per-indent	uint32_t / 4	Number of spaces per indentation level in JSON output. Must be less than or equal to 8. Set to 0 for compact, unformatted JSON.
--stream-blocking-timeout-secs	double / 10.0	Maximum duration in seconds before stream blocking times out. Must be greater than 0.

Size suffixes

The --size option accepts an optional suffix to specify the unit:

• KiB, kibibytes, 1024 bytes

• MiB, mebibytes, 1024 × 1024 bytes

• GiB, gibibytes, 1024 × 1024 × 1024 bytes

When no suffix is provided, the value is interpreted as raw bytes.

Programmatic defaults and CLI precedence

Each option corresponds to a field in the settings struct. You can set default values programmatically before passing settings to the executor. Any value supplied on the command line overrides the programmatic default. See Configure benchmark settings for examples of combining programmatic and command line configuration.