Basic Redis Concepts

1. What is Redis

First, Redis is a key-value storage system that provides 5 types of data storage structure, including List,set,sortset,string,hash, which makes it possible to better describe the structure of the data than the relational database.

Then Redis is a memory-based caching system, and there is a persistence mechanism.

2. Why Redis is present

First, Redis is more flexible; second, reading a DB in a highly concurrent scenario triggers an IO operation, and performance becomes a bottleneck; Redis is memory-based and reads more efficiently.

3. What are the drawbacks of Redis

Redis cannot differentiate hot and cold data by itself, and when no expiration time is set, all data is kept in memory, resulting in memory waste.

Redis has the potential to lose part of the data when it is persisted, and it can cause the response to become slower.

If your application requires more data than is available for memory, Redis is not competent because data in Redis is loaded into memory.

This article is from the "heavy Shoulder" blog, please be sure to keep this source http://527026.blog.51cto.com/517026/1710687

Basic Redis Concepts