uvloop is a fast, drop-in replacement of the built-in asyncio event loop. uvloop is implemented in Cython and uses libuv under the hood.

The project documentation can be found here. Please also check out the wiki.

Performance

uvloop makes asyncio 2-4x faster.

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 about it.

Installation

uvloop requires Python 3.5 or greater and is available on PyPI. Use pip to install it:

$ pip install uvloop

Using uvloop

To make asyncio use uvloop, you can install the uvloop event loop policy:

import asyncio
import uvloop

asyncio.set_event_loop_policy(uvloop.EventLoopPolicy())

or, starting with uvloop 0.12:

import uvloop

uvloop.install()

Building From Source

To build uvloop, you'll need Python 3.5 or greater:

1. Clone the repository:

   $ git clone --recursive [email protected]:MagicStack/uvloop.git
   $ cd uvloop
   

2. Create a virtual environment and activate it, for example:

   $ python3.7 -m venv uvloop-dev
   $ source uvloop-dev/bin/activate
   

3. Install development dependencies:

   $ pip install -r requirements.dev.txt
   

4. Build and run tests:

   $ make && make test
   

License

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