🍉 Melon

Melon is a lightweight distributed job scheduler written in Rust, inspired by Slurm but with added job extension capabilities.

Key Features

• Job submission and management
• Resource allocation and limitations (using cgroups on Linux)
• Job extension functionality
• Simple web UI for job monitoring

Quick Start

1. Clone the repo

   git clone git@github.com:protortyp/melon.git
   cd melon

2. Install tools to /usr/local/bin (will ask for sudo access to move the tools to /usr/local/bin/)

   install.sh
   

3. Set up the scheduler daemon (see Setting up the scheduler)

4. Set up the worker (see Setting up the Worker)

5. Submit a job:

   echo '#!/bin/bash
   #MBATCH -c 4
   #MBATCH -t 0-06:00
   #MBATCH -m 1G
   
   echo "Hello, Melon!"
   ' > job.sh
   
   mbatch job.sh

6. Manage jobs:

   • List jobs: mqueue
   • Extend job time: mextend $JOBID -t 1-00-00
   • Cancel job: mcancel $JOBID
   • Show job details: mshow $JOBID or mshow $JOBID -p for json output

7. Start the UI:

   cd ui
   docker build -t melon-ui .
   docker run -p 80:80 melon-ui

Setting up the Scheduler

Create a new user melond:

sudo adduser melond --no-create-home --disabled-login

Create the configuration file with your preferred settings:

sudo mkdir /var/lib/melon
sudo chown -R melond:melond /var/lib/melon
sudo cp crates/melond/configuration/base.yaml /var/lib/melon
sudo tee /var/lib/melon/production.yaml > /dev/null << EOF
application:
  port: 8080
  host: "127.0.0.1"
database:
  path: "/var/lib/melon/melon.sqlite"
api:
  port: 8088
  host: "127.0.0.1"
EOF

Then, create a new file /etc/systemd/system/melond.service with the following content.

[Unit]
Description=Melon Scheduler
After=network.target

[Service]
Environment=APP_ENVIRONMENT=production
Environment=RUST_LOG=info
Environment="CONFIG_PATH=/var/lib/melon"
ExecStart=/usr/local/bin/melond
User=melond
Restart=always

[Install]
WantedBy=multi-user.target

Start and enable the scheduler:

sudo systemctl daemon-reload
sudo systemctl start melond
sudo systemctl enable melond

Setting up the Worker Cgroups Permissions

Run the setup script using sudo:

sudo bash setup_mworker.sh

Then, create a new file /etc/systemd/system/mworker.service with the following content:

[Unit]
Description=Melon Worker
After=network.target

[Service]
Environment=MELOND_ENDPOINT=127.0.0.1:8080
Environment=MWORKER_PORT=8082
Environment=RUST_LOG=info
ExecStart=/usr/local/bin/mworker --api_endpoint ${MELOND_ENDPOINT} --port ${MWORKER_PORT}
User=mworker
Restart=always

[Install]
WantedBy=multi-user.target

Start and enable the Melon worker:

sudo systemctl daemon-reload
sudo systemctl start mworker
sudo systemctl enable mworker

You can check the status of the service with:

sudo systemctl status mworker

Finally, allow the worker to read from directories using ACLs:

sudo setfacl -R -m u:mworker:rx /home
sudo setfacl -R -d -m u:mworker:rx /home

This will allow the mworker to read job files created by users.