A concurrent networking library for Python that provides performance and scalability of non-blocking IO while writing simple blocking code (no callbacks) using green threads.
Gevent is a coroutine-based Python networking library that uses greenlet to provide a high-level synchronous API on top of libevent (libev after 1.0) event loop.
"The use of gevent is also a performant option but slightly lower than eventlet"
from question "Flask SocketIO & uWSGI causes 'TypeError: 'SocketIO' object is not callable'"
"But this popular wsgi benchmark says eventlet is way slower than gevent"
from question "What does make significant difference of performance between eventlet and gevent?"