About compared with memcached and redis

Outline

redisIs a nosqldatabase, his data is stored in memory, and rediscan synchronize the timing of the in-memory data to disk, that data can be persistent, and compared him memcachedto support more data structure ( string, list列表[队列和栈], set[集合], sorted set[有序集合], hash(hash表)). Related reference documentation: http://redisdoc.com/index.html

redis usage scenarios:

1. Login session storage: Store in the redismiddle, and memcachedcompared the data will not be lost.
2. Top version / counter: for example, some of the show class project, there is often some former anchor ranked number names. There are some articles to read the amount of technology, or Sina microblogging number of points such as praise.
3. As the message queue: such celeryis used redisas an intermediary.
4. Online Now: still show the previous example, the current system will show how much the number of online.
5. Some commonly used data cache: Such as our BBSforum, the plate does not change often, but every access from every home mysqlget in, you can rediscache up in, not every request database.
6. The first 200 articles or reviews cache cache: general users visit the website, only the front part of the article or view a comment, you can put in front of 200 articles and corresponding comments cached. Users access to over, access the database, and after more than 200 articles, put the article before deleting.
7. Friends relationship: friendship use microblogging redisto achieve.
8. Publish and subscribe functions: can be used to make chat software.

   redisAnd memcachedthe comparison:

   	memcached	repeat
   Types of	Pure in-memory database	RAM disk synchronization database
   type of data	When necessary to define the data type fixed value	Do not need
   Virtual Memory	not support	stand by
   Expiration Policy	stand by	stand by
   Storing data security	not support	Data may be synchronized to the dump.db
   Disaster Recovery	not support	You can restore data disk into memory
   distributed	stand by	Master-slave synchronization
   Subscriptions and publishing	not support	stand by