A, Redis Introduction
1.1, related products and compare nosql
1.1.1、Memcached
Advantages: High performance read, a single data type, client support distributed cluster type, the hash consistency, a multi-core structure, a high performance multi-threaded read-write.
Cons: No persistence , caching node failure may occur penetrate, distributed client needs to achieve data synchronization across the room difficult, complex architecture and high expansion
1.1.2 Redis
Advantages: High-performance reading and writing, support multiple data types, data persistence, high-availability architecture, support for custom virtual memory, support for distributed cluster fragmentation, high performance read and write single-threaded
Disadvantages: read and write multi-threaded slower than Memcached
Application Enterprise: Sina, Jingdong, live class platform, web games
1.1.3, Three
Advantages: High-performance read and write, supports three storage engine (ddb, rdb, ldb), support high availability, support for distributed cluster fragmentation, caching support almost all Taobao business.
Cons: Stand-alone case, read and write performance is slower than the other two products
1.1.4, read and write performance comparison
memcached: suitable for multi-user access, a small amount of each user rw
redis: suitable for a small user access, each user a lot rw
1.1.5, using contrast scenes
Memcached: multicore cache service, more suitable for the small number of multi-user concurrent access scenarios
Redis: single-core cache service, single-node case, more suitable for small number of users, application scenarios multiple visits.
Redis is generally stand-alone multi-instance architecture, with redis clusters appear .
1.2, redis Features
1) Redis is an open source, written in ANSI C language, high-key (key-value) caching and persistent storage NoSQL database products support
2) Redis With memory (In-Memory) data set (the DataSet)
3) support a variety of data types
4) run on most POSIX systems, such as Linux, * BSD, OS X, etc.
5) Author: Salvatore Sanfilippo
The main function:
- High-speed read and write
- Rich data types
- Support persistence
- A variety of memory allocation and recovery strategies
- Support Services
- Message queue, the message subscribe
- Support high availability
- Support for distributed cluster fragmentation
1.3, redis scenarios
1) Data Cache
2) web session cache (session cache)
3) Application Leaderboard
4) the message queue
5) publish and subscribe
1.4, redis reference document
1) redis.io
2) download / redis.io
3) redisdoc.com
4) redis.cn