Fixed a long line, a typo, and a few misspellings from [9727].

.. warning::

    You should only use cache-based sessions if you're using the Memcached cache

    backend. The local-memory cache backend doesn't retain data long enough to

    be a good choice, and it'll be faster to use file or database sessions

    directly instead of sending everything through the file or database cache

    backends.

    You should only use cache-based sessions if you're using the Memcached

    cache backend. The local-memory cache backend doesn't retain data long

    enough to be a good choice, and it'll be faster to use file or database

    sessions directly instead of sending everything through the file or

    database cache backends.

Once your cache in configured, you've got two choices for how to store data in

Once your cache is configured, you've got two choices for how to store data in

the cache:

    * Set :setting:`SESSION_ENGINE` to

      ``"django.contrib.sessions.backends.cache"`` for a simple caching session

      store. Session data will be stored directly your cache. However, session

      data may not be persistant: cached data can be evicted if the cache fills

      data may not be persistent: cached data can be evicted if the cache fills

      up or if the cache server is restarted.

    * For persistant, cached data, set :setting:`SESSION_ENGINE` to

    * For persistent, cached data, set :setting:`SESSION_ENGINE` to

      ``"django.contrib.sessions.backends.cached_db"``. This uses a

      write-through cache -- every write to the cache will also be written to

      the database. Session reads only use the database if the data is not

      already in the cache.

Both session stores are quite fast, but the simple cache is faster because it

disreguards persistance. In most cases, the ``cached_db`` backend will be fast

disregards persistence. In most cases, the ``cached_db`` backend will be fast

enough, but if you need that last bit of performance, and are willing to let

session data be expunged from time to time, the ``cache`` backend is for you.