The same and different points of Mongodb and Redis

Both MongoDB and Redis are NoSQL, using structured data storage. There is a certain difference in the use of the scene, which is mainly due to
In the process of memory mapping, the processing method of persistence is different. MongoDB recommends cluster deployment, more considering the cluster scenario, Redis
More emphasis is on process sequential writes, although cluster support is also limited to master-slave mode.

Indicators	MongoDB (v2.4.9)	Redis (v2.4.17)	Comparison notes
Implementation language	C++	C + +	-
Agreement	BSON, Custom Binary	Class Telnet	-
Performance	Memory dependent, higher TPS	Memory dependent, TPS very high	Redis is better than MongoDB
operability	Rich data expression, index, most similar to relational database, support rich query language	Data-rich, less IO	MongoDB is better than Redis
Memory and Storage	Suitable for large data volume storage, relying on system virtual memory management, using image file storage, memory share is high, the official recommendation is independently deployed in 64-bit system (32 bits have the maximum 2.5G file limit, 64 bit no change limit)	After Redis2.0, the virtual memory feature is added to break the physical memory limit; Data can be set to timeliness, similar to Memcache	Different application point of view, each has advantages
Availability of	Support Master-slave,replicaset (internal use of Paxos election algorithm, automatic fault recovery), auto sharding mechanism, blocking the failover and segmentation mechanism to the client	Rely on the client to implement the distributed read and write, master-slave replication, every time from the node reconnect to the primary node to rely on the entire snapshot, no incremental replication, automatic sharding is not supported, requires a dependent program to set the consistent hash mechanism	MongoDB is better than Redis; On a single point problem, MongoDB application is simple, relative user transparent, Redis is more complex, need the client to actively solve. (MongoDB is typically combined with replica sets and sharding features, replica sets focuses on high availability and high reliability, while Sharding focuses on performance, easy scalability)
Reliability	From the 1.8 release, the binlog approach (MySQL is also used in this way) supports persistence, increasing reliability	relies on snapshots for persistence, aof enhances reliability, and improves reliability while impacting access performance	MongoDB is better than Redis
Consistency	Do not support things, by the client's own assurance	To support things, weaker, only to ensure that the operations of things in order to execute	Redis is better than MongoDB
Data analysis	Built-in data analysis capabilities (MapReduce)	Not supported	MongoDB is better than Redis
Application Scenarios	Increased access efficiency for massive data	Performance and operation of smaller data volumes	MongoDB is better than Redis

The same and different points of Mongodb and Redis