redis caching mechanism

Redis provides an efficient caching mechanism, using key-value pair structures to store data, and using different data structures to optimize different types of data storage. When the cache reaches capacity limit, it uses various eviction strategies (such as LRU, LFU, TTL) to evict data. The advantages of the Redis caching mechanism include improved application performance, reduced latency, improved reliability and simplified development.

Redis’ caching mechanism

Redis is a highly scalable in-memory database that provides a A fast and reliable caching mechanism that can significantly improve application performance.

Working principle

Redis uses a key-value pair structure to store data. When an application needs to read data, it first checks the Redis cache. If the data is in cache, it is fetched directly from Redis, thus avoiding expensive queries to the underlying database. If the data is not in the cache, the application fetches the data from the database and stores it in the Redis cache for quick access next time.

Data structure

Redis uses different data structures for different types of data, including:

• String: Used to store simple text data.
• List: Used to store ordered collections.
• Collection: Used to store unordered collections.
• Hash: used to store a collection of key-value pairs.
• Ordered collection: used to store key-value pairs with scores.

Elimination Strategy

When the Redis cache reaches its capacity limit, it needs to decide which data to evict. Redis provides a variety of elimination strategies, including:

• LRU (least recently used): Eliminate the least recently used key-value pair.
• LFU (least frequently used): Eliminate the least frequently used key-value pairs.
• TTL (Time to Live): Eliminate key-value pairs with expiration time.

Advantages

The Redis caching mechanism provides the following advantages:

• Improving performance: By cache Fetching data from the database avoids costly queries to the underlying database, thereby improving application performance.
• Reduce Latency: Cache data is located in memory and therefore accessed very quickly, thus reducing application response time.
• Improve reliability: Redis is a high-availability system, which can still ensure data consistency even if a failure occurs.
• Simplify development: Redis provides a simple and easy-to-use API that allows developers to easily integrate caching mechanisms into applications.

The above is the detailed content of redis caching mechanism. For more information, please follow other related articles on the PHP Chinese website!