Introduction to Redis, advantages

Redis is a high performance key-value database that is completely open source and free and complies with the BSD protocol.

Redis and other key-value caching products have the following three characteristics:

· Redis supports persistence of data. Data in memory can be saved to disk, which can be reloaded for use upon restart.

· Redis not only supports simple key-value type data, but also provides storage of list, set, zset, hash and other data structures.

· Redis supports data backup, namely in master-slave mode.

Redis advantage

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– Redis can read 110000 times /s and write 81000 times /s.

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— Redis supports Strings, Lists, Hashes, Sets and Ordered Sets data types for binary cases.

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– All operations in Redis are atomic, meaning that they are either executed on success or not executed at all. Individual operations are atomic. Multiple operations also support transactions, namely atomicity, wrapped in MULTI and EXEC instructions.

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Redis also supports publish/subscribe, notification, key expiration, and more.

How is Redis different from other key-value stores?

· Redis has more complex data structures and provides atomic operations on them, which is a different evolutionary path from other databases. Redis data types are transparent to programmers while being based on basic data structures without additional abstractions.

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· Redis runs in memory but can persist to disk, so there is a memory tradeoff for high-speed reads and writes to different data sets, since the amount of data cannot be greater than hardware memory. Another advantage of an in-memory database is that it is much easier to operate in memory than the same complex data structures on disk, allowing Redis to do a lot of things with a lot of internal complexity. At the same time, they are compact in terms of disk formats and are produced in an appending manner because they do not require random access.