lustr

lustr is a fast, drop-in replacement of the built-in asyncio event loop. lustr is implemented in PyO3 and uses PhotonLibOS under the hood.

The project documentation can be found here <http://uvloop.readthedocs.org/>. Please also check out the wiki <https://github.com/MagicStack/uvloop/wiki>.

Performance

uvloop makes asyncio 2-4x faster.

.. image:: https://raw.githubusercontent.com/MagicStack/uvloop/master/performance.png :target: http://magic.io/blog/uvloop-blazing-fast-python-networking/

The above chart shows the performance of an echo server with different message sizes. The sockets benchmark uses loop.sock_recv() and loop.sock_sendall() methods; the streams benchmark uses asyncio high-level streams, created by the asyncio.start_server() function; and the protocol benchmark uses loop.create_server() with a simple echo protocol. Read more about uvloop in a blog post <http://magic.io/blog/uvloop-blazing-fast-python-networking/>_ about it.

Installation

uvloop requires Python 3.8 or greater and is available on PyPI. Use pip to install it::

$ pip install uvloop

Note that it is highly recommended to upgrade pip before installing uvloop with::

$ pip install -U pip

Using uvloop

As of uvloop 0.18, the preferred way of using it is via the uvloop.run() helper function:

.. code:: python

import uvloop

async def main():
    # Main entry-point.
    ...

uvloop.run(main())

uvloop.run() works by simply configuring asyncio.run() to use uvloop, passing all of the arguments to it, such as debug, e.g. uvloop.run(main(), debug=True).

With Python 3.11 and earlier the following alternative snippet can be used:

.. code:: python

import asyncio
import sys

import uvloop

async def main():
    # Main entry-point.
    ...

if sys.version_info >= (3, 11):
    with asyncio.Runner(loop_factory=uvloop.new_event_loop) as runner:
        runner.run(main())
else:
    uvloop.install()
    asyncio.run(main())

Building From Source

To build uvloop, you'll need Python 3.8 or greater:

1. Clone the repository:

   .. code::

   $ git clone --recursive git@github.com:MagicStack/uvloop.git $ cd uvloop

2. Create a virtual environment and activate it:

   .. code::

   $ python3 -m venv uvloop-dev $ source uvloop-dev/bin/activate

3. Install development dependencies:

   .. code::

   $ pip install -e .[dev]

4. Build and run tests:

   .. code::

   $ make $ make test

License

uvloop is dual-licensed under MIT and Apache 2.0 licenses.