hpc_eff

Energy Optimization Governor for HPC systems.
Reads power, price, and CO₂ intensity data, then sets the min and max frequency based on a calculated rating.

All the functionality and code logic located in src/hpc_eff stem from https://gitlab.cesnet.cz/dexter/hpc_eff.

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Overview

hpc_eff is designed to be run periodically (e.g., via cron every few minutes) under root.
It evaluates current energy conditions, prints debug logs if enabled, and sets the min and max CPU frequencies accordingly.

Main steps performed:

1. Load configuration from /etc/hpc_eff/config.ini
2. Fetch current electricity price
3. Read current power usage via a configured shell command
4. Read current CPU frequency
5. Retrieve available CPU frequencies and governors
6. Fetch historical energy price averages and classify current price
7. Fetch last 24h CO₂ values and calculate rating
8. Apply min and max CPU frequencies based on rating

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Logging & Monitoring

The application maintains two types of logs:

• SQLite Database: Detailed historical logs stored at /var/lib/hpc_eff/history.db.
• JSON State File: A consolidated state file at /var/lib/hpc_eff/state.json containing:
  • static: System metadata (score, power command, active plugins).
  • current: Latest evaluation results (rating, price, power, temp, etc.).
  • history: A rolling history of previous evaluations.

These can be configured in /etc/hpc_eff/config.ini:

[logging]
db_path = /var/lib/hpc_eff/history.db
state_json_path = /var/lib/hpc_eff/state.json
history_length = 10

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Installation

1. Clone the repository:

   git clone git@github.com:CESNET/hpc_eff.git
   cd hpc_eff

2. Install the dependencies:

   sudo dnf install ipmitool cpufrequtils make kernel-tools rpm-build rpmdevtools -y

3. Build and install:

   make

4. Configure with your API key from nowtricity:

   sudo vi /etc/hpc_eff/config.ini

5. To read from the created database:

   sudo cp /var/lib/hpc_eff/history.db ~/history.db
   sqlite3 ~/history.db

   Inspect tables and data:

   .tables
   .schema cpu_settings_log 
   SELECT * FROM cpu_settings_log LIMIT 10;
   

6. You can enable or disable a system cronjob using command-line switches.

   hpc-eff --enable
   hpc-eff --disable
   

   By default, the cronjob runs every 10 minutes and is installed at /etc/cron.d/hpc-eff. You can customize the path and interval:

   hpc-eff --enable --cron-path /custom/path --cron-interval 5