.. image:: https://upload.wikimedia.org/wikipedia/commons/f/f4/Logo_EPFL.svg
   :alt: EPFL logo
   :width: 75px
   :align: right

==============
decentralizepy
==============

decentralizepy is a framework for running distributed applications (particularly ML) on top of arbitrary topologies (decentralized, federated, parameter server).
It was primarily conceived for assessing scientific ideas on several aspects of distributed learning (communication efficiency, privacy, data heterogeneity etc.).

-------------------------
Setting up decentralizepy
-------------------------

* Fork the repository.
* Clone and enter your local repository.
* Check if you have ``python>=3.8``. ::

    python --version

* (Optional) Create and activate a virtual environment. ::

    python3 -m venv [venv-name]
    source [venv-name]/bin/activate

* Update pip. ::

    pip3 install --upgrade pip
    pip install --upgrade pip

* On Mac M1, installing ``pyzmq`` fails with `pip`. Use `conda <https://conda.io>`_.
* Install decentralizepy for development. (zsh) ::

    pip3 install --editable .\[dev\]

* Install decentralizepy for development. (bash) ::

    pip3 install --editable .[dev]

* Download CIFAR-10 using ``download_dataset.py``. ::

    python download_dataset.py

* (Optional) Download other datasets from LEAF <https://github.com/TalwalkarLab/leaf> and place them in ``eval/data/``.

----------------
Running the code
----------------

* Follow the tutorial in ``tutorial/``. OR,
* Generate a new graph file with the required topology using ``generate_graph.py``. ::

    python generate_graph.py --help

* Choose and modify one of the config files in ``eval/{step,epoch}_configs``.
* Modify the dataset paths and ``addresses_filepath`` in the config file.
* In eval/run.sh, modify arguments as required.
* Execute eval/run.sh on all the machines simultaneously. There is a synchronization barrier mechanism at the start so that all processes start training together.

------
Citing
------

Cite us as ::

    @inproceedings{decentralizepy,
   author = {Dhasade, Akash and Kermarrec, Anne-Marie and Pires, Rafael and Sharma, Rishi and Vujasinovic, Milos},
   title = {Decentralized Learning Made Easy with DecentralizePy},
   year = {2023},
   isbn = {9798400700842},
   publisher = {Association for Computing Machinery},
   address = {New York, NY, USA},
   url = {https://doi.org/10.1145/3578356.3592587},
   doi = {10.1145/3578356.3592587},
   booktitle = {Proceedings of the 3rd Workshop on Machine Learning and Systems},
   pages = {34-41},
   numpages = {8},
   keywords = {peer-to-peer, distributed systems, machine learning, middleware, decentralized learning, network topology},
   location = {Rome, Italy},
   series = {EuroMLSys '23}
   }

-------------------------
Built with DecentralizePy
-------------------------

.. _`Epidemic Learning`: https://arxiv.org/abs/2310.01972/

`Epidemic Learning`_
--------------------

Tutorial
    ``tutorial/EpidemicLearning``
Source files
    ``src/node/EpidemicLearning/``
Cite
    ``Martijn de Vos, Sadegh Farhadkhani, Rachid Guerraoui, Anne-Marie Kermarrec, Rafael Pires, and Rishi Sharma. Epidemic Learning: Boosting Decentralized Learning with Randomized Communication. In Thirty-seventh Conference on Neural Information Processing Systems (NeurIPS), 2023.``

.. _`Get More for Less in Decentralized Learning Systems`: https://ieeexplore.ieee.org/document/10272515/

`Get More for Less in Decentralized Learning Systems`_
------------------------------------------------------

Tutorial
    ``tutorial/JWINS``
Source files
    ``src/sharing/JWINS/``
Cite
    ``Akash Dhasade, Anne-Marie Kermarrec, Rafael Pires, Rishi Sharma, Jeffrey Wigger, and Milos Vujasinovic. Get More for Less in Decentralized Learning Systems. In IEEE 43rd International Conference on Distributed Computing Systems (ICDCS), 2023.``


------------
Contributing
------------

* ``isort`` and ``black`` are installed along with the package for code linting.
* While in the root directory of the repository, before committing the changes, please run ::

    black .
    isort .

-------
Modules
-------

Following are the modules of decentralizepy:

Node
----
* The Manager. Optimizations at process level.

Dataset
-------
* Static

Training
--------
* Heterogeneity. How much do I want to work?

Graph
-----
* Static. Who are my neighbours? Topologies.

Mapping
-------
* Naming. The globally unique ids of the ``processes <-> machine_id, local_rank``

Sharing
-------
* Leverage Redundancy. Privacy. Optimizations in model and data sharing.

Communication
-------------
* IPC/Network level. Compression. Privacy. Reliability

Model
-----
* Learning Model