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How to use Redis and Memcached in php

Differences 1. Redis is a storage database. Memcache can also cache photos. Redis and Memcache store data in memory and are memory databases. However, Memcache can also cache other things like photos and videos. Redis not only supports simple k/v type data, but also provides storage of data structures such as list, set, and hash. Expiration strategy, memcache is specified when setting. For example, setkey1008 never expires. redis can be set via expire. For example, expirename10. Storage security, after memcache is closed, redis data disappears and can be regularly saved on the disk.

Jun 01, 2023 pm 05:46 PM

PHPredismemcached

How to configure high availability and persistence in redis

1. Redis High Availability 1. Overview of Redis High Availability In web servers, high availability refers to the time the server can be accessed normally, and the measurement standard is how long it can provide normal services (99.9%, 99.99%, 99.999%, etc. wait). [Related recommendation: Redis video tutorial] However, in the context of Redis, the meaning of high availability seems to be broader. In addition to ensuring the provision of normal services (such as master-slave separation, fast disaster recovery technology), it is also necessary to consider the expansion of data capacity, data Security will not be lost etc. 2. Redis high availability strategy In Redis, the technologies to achieve high availability mainly include persistence, master-slave separation, sentinels and clusters. High availability strategy shows that persistence is the most

Jun 01, 2023 pm 05:38 PM

redis

How to solve the problem of insufficient memory when using redis in php

Solution to insufficient memory of redis in PHP: 1. Set the maximum memory size of Redis to 100M through the configuration file or command; 2. Get the current memory elimination policy; 3. Modify the elimination policy through the "configsetmaxmemory-policyallkeys-lru" command. Memory size occupied by Redis We know that Redis is a memory-based key-value database. Because the memory size of the system is limited, we can configure the maximum memory size that Redis can use when using Redis. 1. Configure through the configuration file. Add the following to the redis.conf configuration file under the Redis installation directory.

Jun 01, 2023 pm 04:37 PM

PHPredis

Redis data structure type example code analysis

intset When the set collection stores integers, encoding is the intset type (small integer collection) typedefstructintset{int32encoding;int32length;intcontents[];} field description description encoding determines whether the integer bit width is 16-bit, 32-bit, or 64-bit enumeration representation The number of length elements, contents, is an integer array that stores element values. Intset stores the elements in order from small to large. When storing elements, decide whether to upgrade the encoding according to the integer size, find the position where the element is to be inserted, if it is not the last position, the elements after the position will be

Jun 01, 2023 pm 02:16 PM

redis

How to cache database data to Redis through custom cache annotations in SpringBoot

To implement, first create a new table bus_student in Mysql and then use code generation based on this table to generate code for each layer of front-end Vue and back-end and add menus. Then come to the background code, the relevant dependencies and tool classes for operating redis have been added to the background framework. But here you also need to add the aspect dependency org.springframeworkspring-aspects4.3.14.RELEASE and then create a new redis cache annotation packagecom.ruoyi.system.redisAop;importjava.lang.annotation.Ele where the configuration class is stored.

Jun 01, 2023 pm 01:49 PM

数据库redisSpringBoot

How to install Redis in Centos7

In the early stage of preparation, you can download the redis installation package for 1.1. You can also download other versions. I will download the 5.0.8 version here. 1.2 Upload the installation package Upload the downloaded installation package to the specified directory on the server, and then decompress it through tar-zxvfxxxx, such as: 2. Check that gcc installation of redis requires a c environment, so offline installation requires downloading some dependent installation packages. 2.1 Download address: https://vault.centos.org/7.0.1406/os/x86_64/Packages/cpp-4.8.2-16.el7.x86_64.rpmgcc-4.8.2-16.el7.x86_64.rpmglibc- 2.

Jun 01, 2023 pm 01:04 PM

redisCentOS

How to build and use redis5 cluster under Centos7

1. Briefly explain that there should be at least three nodes in the cluster, and each node has a backup node. 6 servers are required. If conditions are limited, you can build a pseudo-distributed cluster. The following steps are to build a redis cluster with 6 nodes on a Linux server. 2. Steps to create a cluster 2.1. Create a directory. Create a new directory: mkdir/usr/local/redis-cluster2.2. Download the source code and unzip and compile wgethttp://download.redis.io/releases/redis-5.0.0.tar.gztarxzfredis -5.0.0.tar.gzcdredis-5.0.0makemak

Jun 01, 2023 am 11:37 AM

rediscentos7

What causes Redis breakdown avalanche and how to solve it

1. Preface As we all know, one of the bottlenecks of computers is IO. In order to solve the problem of mismatch between memory and disk speed, cache is created to put some hot data in the memory and access it as needed, which reduces the request to connect to the database. link to prevent the database from hanging. It should be noted that whether it is breakdown or the penetration and avalanche mentioned later, it is all under the premise of high concurrency, such as when a certain hot key in the cache fails. 2. There are two main causes of the problem: 1. Key expired; 2. Key was eliminated by page replacement. The first reason is that in Redis, Key has an expiration time. If the key expires at a certain moment (if the mall is doing an event, starting at midnight), then all query requests for a certain product after midnight will be overwhelmed.

Jun 01, 2023 am 10:55 AM

redis

How to implement Caffeine+Redis second-level cache based on Spring Cache

The details are as follows: 1. Let’s talk about what is hard-coded cache? Before learning SpringCache, I often used caching in a hard-coded way. Let's take a practical example. In order to improve the query efficiency of user information, we use caching for user information. The sample code is as follows: @AutowireprivateUserMapperuserMapper; @AutowireprivateRedisCacheredisCache;//Query users publicUsergetUserById(LonguserId){//Define cache keyStringcacheKey= "userId_

Jun 01, 2023 am 10:13 AM

Springrediscache

What are the free tools for high-performance in-memory database Redis?

1. Redis Memory Analyzer (RMA) RMA is one of the most comprehensive FOSS memory analyzers available for Redis. It supports three different levels of detailed analysis. Global - overview of memory usage information; Scanner - memory usage information at the highest level keyspace/prefix level, that is, using the shortest common prefix; RAM - lowest level keyspace/prefix, that is, using the longest common prefix. In global mode, RMA provides some advanced statistics such as number of keys, system memory, resident set size, key space size, etc. The only feature is "key space overhead", that is, the memory used by the Redis system to store key space related information, such as pointers to list data structures; in scan mode, obtain

Jun 01, 2023 am 08:41 AM

redis

Redis optimization example analysis

The memory dimension controls the length of the key. The key generally uses a string, and the underlying data structure of the string is SDS. The SDS structure will contain metadata information such as string length and allocated space size. When the length of the key string increases, , the metadata in SDS will also occupy more memory space. In order to reduce the space occupied by the key, we can use the corresponding English abbreviation according to the business name to represent it. For example, user is represented by u, and message is represented by m. To avoid storing bigkey, we must pay attention to both the length of the key and the size of the value. Redis uses a single thread to read and write data. The read and write operations of bigkey will block the thread and reduce the processing efficiency of Redis. how

Jun 01, 2023 am 08:38 AM

redis

How to use redigo in go redis

Installing the go-redis third-party library encapsulates many functions for us to execute Redis commands, while the redigo third-party library only has one Do function to execute Redis commands, which is closer to using redis-cli to operate Redis. go-redis supports connecting to sentry and cluster mode Redisgogetgithub.com/gomodule/redigogogetgithub.com/go-redis/redis/v8 link Redisfuncmain(){c,err:=redis.Dial("tcp","localhost:6379"

Jun 01, 2023 am 08:37 AM

Goredisredigo

What are the annotations for springboot integrated redis?

Introduction to redis: Redis is one of the more popular NOSQL systems currently. It is an open source key-value storage system written in ANSIc language (different from MySQL's two-dimensional table storage.). Similar to Memcache, but it largely compensates for the shortcomings of Memcache. Like Memcache, Redis data is cached in computer memory. The difference is that Memcache can only cache data in memory and cannot automatically and regularly write to the hard disk. This means that when the power is cut off or restarted, the memory is cleared and the data is lost. . Therefore, the application scenario of Memcache is suitable for caching data that does not need to be persisted. The difference with Redis is that it will be periodic

May 31, 2023 pm 11:43 PM

redisSpringBoot

How to configure and use redis

Spring-data-redis is the redis support part of the spring-data module, referred to as "SDR". It provides a high degree of encapsulation based on the jedis client API and integration with the spring container. In fact, the jedis client is simple and light enough. magnitude, while spring-data-redis is suspected of being "over-designed". The jedis client has the following shortcomings in programming implementation: 1) Connection management lacks automation, and the design of connection-pool lacks necessary container support. 2) Data operations need to pay attention to "serialization"/"deserialization" because of the client API of jedis

May 31, 2023 pm 11:31 PM

redis