How to implement the underlying data structure of redis
Implementation of Redis underlying data structure
Redis is an in-memory data structure storage that uses efficient data structures to implement various data types. These underlying data structures include:
1. Hash Table
The hash table is used to store key-value pairs, where the key is hashed into a value and points to the corresponding data. Redis uses a hash table implementation called Space Saving, which can efficiently store large numbers of keys.
2. Skip List
A jump table is an ordered linked list where certain nodes are skipped for quick searches. Redis uses skip tables for ordered data structures such as strings, lists, and collections.
3. Dictionary Tree (Trie)
A dictionary tree is a tree-shaped data structure in which each node represents a character and the leaf node stores words. Redis uses a dictionary tree to implement prefix matching and autocomplete functions.
4. Int Array
An array of integers is used to store ordered integers. Redis uses integer arrays to implement data structures such as counters, rankings, and time series.
5. Compressed List (ZipList)
A compressed list is a compact data structure that stores small lists of strings and integers. It uses bit markers to represent the type and length of the element, saving space.
6. Linked List
A linked list is a linear data structure in which each node points to the next node. Redis uses linked lists to implement data structures such as bidirectional linked lists, queues and stacks.
7. RDB/AOF file
RDB and AOF files are used to persist Redis data to disk. An RDB file is a binary file, while an AOF file is a text file that records commands executed by Redis.
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