# Energy Benchmarking Tool

The energy benchmarking Rust crate can be added to your project with `cargo add energy-bench`.
The tool is continuously being updated, so please make sure you are using the most recent version.

Tool for benchmarking the energy consumption of programs.
Idle energy consumption, as well as energy consumed by data generation and cleanup, are not subtracted from the results.
A new benchmark builder is created with `EnergyBenchBuilder::new()`.

Check out the `example` folder for a few examples, and check the `.gitlab-ci.yml` for an example of how to run the
Software Energy Lab pipeline.

Some programs are too short-running to provide accurate energy measurements.
To avoid this, the benchmark can be repeated until a given amount of time has passed: `set_min_measurement_duration`.
By default, benchmarks are run for at least 100ms.

## RAPL permissions

If you want to run this locally, you will likely need elevated permissions for reading RAPL energy data.

I suggest adding a new `rapl` group.

```bash
sudo addgroup rapl
sudo usermod -aG rapl $(whoami)
```

And then adding entries to `/etc/sysfs.conf` for your RAPL domains and subdomains.
Check your folder hierarchy in `/sys/class/powercap/` to determine which domains
you have available to your CPU.

Then for each domain, add the following lines to `/etc/sysfs.conf`.
(Requires `sysfsutils` to be installed.)

For example, for package 0:

```bash
mode class/powercap/intel-rapl:0/energy_uj = 0440
owner class/powercap/intel-rapl:0/energy_uj = root:rapl
```

And for its first subdomain:

```bash
mode class/powercap/intel-rapl:0:0/energy_uj = 0440
owner class/powercap/intel-rapl:0:0/energy_uj = root:rapl
```

Finally, restart the `sysfsutils` service.

```bash
sudo systemctl restart sysfsutils
```
