Memcached

Settings

• Sole

  CACHES = {
      'default': {
          'BACKEND': 'django.core.cache.backends.memcached.MemcachedCache',
          'LOCATION': '127.0.0.1:11211',
      }
  }
  

• Multi

  CACHES = {
      'default': {
          'BACKEND': 'django.core.cache.backends.memcached.MemcachedCache',
          'LOCATION': [
              '172.19.26.240:11211',
              '172.19.26.242:11211',
          ]
      }
  }
  

BACKEND

• MemcachedCache

  • Install Binding

    pip install python-memcached
    

• PyLibMCCache

  • Install Lib

    sudo apt-get install libmemcached-dev  # Ubuntu
    sudo brew install libmemcached         # Mac OS X
    

  • Install Bingding

    pip install pylibmc
    

Usage

• Basic

  >>> from django.core.cache import cache
  
  >>> cache.set('my_key', 'hello, world!', 30)
  >>> cache.get('my_key')
  'hello, world!'
  

Problems

• Using python-memcached happens multi server's data outer-sync
  • How does django handle multiple memcached servers?
  • Solved by changing to use django.core.cache.backends.memcached.PyLibMCCache (pylibmc)
• When List is too large, set/get is too slow
  • Use String replace of List, json.dumps() before set, json.loads() after get

References

[1] Docs@DjangoProject, Django’s cache framework

[2] python-memcached@Github, python-memcached — A python memcached client library

[3] pylibmc@Github, pylibmc — A Python wrapper around the libmemcached interface from TangentOrg