Piston workers (slurm)

We have built a piston package to run IOI problems.

To launch a fleet of piston workers on a slurm cluster, you can adapt the paths in launch_piston_workers.sh and launch_single_piston.sh and run:

bash

slurm/piston/launch_piston_workers.sh (number of workers to launch)

This command will launch a slurm job for each worker, which will be called piston-worker-<port>, where <port> is the port where the worker will be listening.

First time setup

You will need to install the IOI package in the workers.

Launch a single worker:

bash

slurm/piston/launch_piston_workers.sh 1

Assuming it's running on ip-10-53-86-146:1234, send the package install request:

For IOI:

bash

curl -X POST http://ip-10-53-86-146:1234/api/v2/packages -H "Content-Type: application/json" -d '{"language": "cms_ioi", "version": "1.0.0"}'

For CodeForces:

bash

curl -X POST http://ip-10-53-86-146:1234/api/v2/packages -H "Content-Type: application/json" -d '{"language": "codeforces", "version": "1.0.0"}'

You can now launch more workers and due to the shared mounted packages directory, they should already have the package installed.

To have the main script find the workers automatically, you can export the following environment variable:

bash

export PISTON_ENDPOINTS=slurm

Alternatively your can add PISTON_ENDPOINTS=slurm to your .env file.

You can also change PISTON_MAX_REQUESTS_PER_ENDPOINT, which tries to limit how many simultaneous requests each worker will handle (1 by default). Keep in mind that this is a local limit and in distributed setups, as there is no global limit, workers might sometimes be overwhelmed when some processes hit the same worker.

If you would like to adapt the code to run without piston, please see the ioi repo. For CodeForces, you should implement the run and compile scripts.

Piston workers (local docker)

This will launch a single worker in a docker container. Consider launching multiple workers for better scalability. Replace 2000 with the port you want to use. Make sure to change /path/to/local/packages to the path you want to persist for package installs.

bash

docker run -d \
  --name piston_worker \
  -v /path/to/local/packages:/piston/packages \
  -e PORT=2000 \
  -e PISTON_COMPILE_TIMEOUT=60000 \
  -e PISTON_RUN_TIMEOUT=60000 \
  -e PISTON_OUTPUT_MAX_SIZE=1000000000 \
  -e PISTON_MAX_FILE_SIZE=1000000000 \
  -e PISTON_DISABLE_NETWORKING=true \
  -e PISTON_REPO_URL=https://github.com/guipenedo/piston/releases/download/pkgs/index \
  -p 2000:2000 \
  --entrypoint /bin/bash \
  ghcr.io/engineer-man/piston@sha256:63b5654156a89c5a2ad281aface21416615d62ec056d88efe8fcd307ce73575a \
  -c "sed -i '/app.use(body_parser.urlencoded/c\    app.use(body_parser.urlencoded({ extended: true, limit: \"512mb\" }));' src/index.js && \
      sed -i '/app.use(body_parser.json/c\    app.use(body_parser.json({ limit: \"512mb\" }));' src/index.js && \
      node src"

Install the package: For IOI:

bash

curl -X POST http://localhost:2000/api/v2/packages -H "Content-Type: application/json" -d '{"language": "cms_ioi", "version": "1.0.0"}'

For CodeForces:

bash

curl -X POST http://localhost:2000/api/v2/packages -H "Content-Type: application/json" -d '{"language": "codeforces", "version": "1.0.0"}'

Remember to set PISTON_ENDPOINTS:

bash

export PISTON_ENDPOINTS=http://localhost:2000/api/v2,http://localhost:2001/api/v2,http://localhost:2002/api/v2