Redis6.0 new features

One 、ACL Access control list

Redis ACL yes Access Control List（ Access control list ） Abbreviation , This function allows some connections to be restricted according to the commands that can be executed and the keys that can be accessed

stay Redis 5 Before the release ,Redis The security rule is only password control And through rename To adjust high-risk orders, such as flushdb,KEYS* ,shutdown etc. .Redis 6 Provide ACL More fine-grained permission control for users ：
（1） Access rights : User name and password
（2） Orders that can be executed
（3） It can be operated KEY

Refer to the official website ：https://redis.io/topics/acl

1. Use acl list The command displays the user permission column

2. Use acl cat command

（1） View add permission instruction category

（2） Add the parameter type name to view the specific commands under the type

3. Use acl whoami Command to view the current user

4. Use acl setuser Command to create and edit users ACL

（1）ACL The rules
Here are the valid ACL List of rules , Some rules are only used to activate or delete flags , Or to users ACL A single word that performs a given change . Other rules are character prefixes , They are the same as the command or category name 、 Key mode, etc

（2） Create new user default permissions by command

acl setuser user1

In the example above , I didn't specify any rules at all . If the user doesn't exist , This will use just created To create a user . If the user already exists , Then the above command will not perform any operation

（3） Set user name 、 password 、ACL jurisdiction 、 And enabled users

acl setuser user2 on >password ~cached:* +get # user2 Only allowed cached: At the beginning key Conduct get operation 

(4) Switching users , Verify permissions

auth  user   password 

Two 、IO Multithreading

1. brief introduction

Redis6 Finally support multithreading , Say goodbye to single thread ？

IO Multithreading actually refers to the interactive part of the client The Internet IO Interactive processing module multithreading , Instead of multithreading commands ,Redis6 Executing commands is still single threaded

2. Principle framework

Redis 6 Join multithreading , But follow Memcached Such from IO There are some differences in the implementation mode of processing to data access multithreading

Redis The multithreading part is only used to process network data reading and writing and protocol parsing , Executing commands is still single threaded . The reason for this design is that we don't want to be complicated by multithreading , Need to control key、lua、 Business , LPUSH/LPOP And so on

The overall design is as follows :

in addition , Multithreaded network IO It is also not enabled by default , Need to reconfigure the file redis-6379.conf Middle configuration

io-threads-do-reads yes
io-threads 4

3、 ... and 、 Cluster tool support Cluster

The old version Redis If you want to build a cluster, you need to install it separately ruby Environmental Science ,Redis 5 take redis-trib.rb Integrated into redis-cli. Another official redis-benchmark Tools start to support cluster The model , Through the way of multithreading, the pressure test is carried out for multiple pieces .

Four 、Redis6 Other new features

1. RESP3 new Redis Communication protocol ： Optimize the communication between server and client

2. Client side caching Client cache ： be based on RESP3 The client cache function of the protocol . by Further improve the performance of cache , The data that the client often accesses cache To client . Reduce TCP The Internet Interaction .

3. Proxy Cluster agent mode ：Proxy function , Give Way Cluster It has the same access method as single instance , Reduce your use cluster Threshold . However, it should be noted that the agent does not change Cluster The functional limitations of , No The supported commands will not support , For example, cross slot More Key operation .

4. Modules API Redis 6 Middle module API Great development progress , because Redis Labs To develop complex functions , From one Use it at the beginning Redis modular .Redis Can become a framework , utilize Modules To build different systems , and There is no need to write from scratch and then BSD The license .Redis From the beginning, it was an open system for writing various systems platform