Gevent

PyMongo supports Gevent. Simply call Gevent’s monkey.patch_all() before loading any other modules:

>>> # You must call patch_all() *before* importing any other modules
>>> from gevent import monkey; monkey.patch_all()
>>> from pymongo import MongoClient
>>> client = MongoClient()

PyMongo’s Gevent support means that start_request() ensures the current greenlet (not merely the current thread) uses the same socket for all operations until end_request() is called. See the requests documentation for details on requests in PyMongo.

Using Gevent With Threads

If you need to use standard Python threads in the same process as Gevent and greenlets, run monkey.patch_socket(), rather than monkey.patch_all(), and create a MongoClient with use_greenlets=True. The MongoClient will use a special greenlet-aware connection pool.

>>> from gevent import monkey; monkey.patch_socket()
>>> from pymongo import MongoClient
>>> client = MongoClient(use_greenlets=True)

An instance of MongoReplicaSetClient created with use_greenlets=True will also use a greenlet-aware pool. Additionally, it will use a background greenlet instead of a background thread to monitor the state of the replica set.

>>> from gevent import monkey; monkey.patch_socket()
>>> from pymongo.mongo_replica_set_client import MongoReplicaSetClient
>>> rsc = MongoReplicaSetClient(
...     'mongodb://localhost:27017,localhost:27018,localhost:27019',
...     replicaSet='repl0', use_greenlets=True)

Setting use_greenlets is unnecessary under normal circumstances; simply call patch_all to use Gevent with PyMongo.

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