Programmer Group

preface Tip: Here you can add the general contents to be recorded in this article: For example, with the continuous development of artificial intelligence, machine learning technology is becoming more and more important. Many people have started learning machine learning. This paper introduces the basic content of machine learning. Ti ...

Go—Redis 1, Basic introduction, installation and principle of Redis 1. Basic introduction: ① Redis is a NoSQL database (non relational database) 💨 Official website ② Redis (remote dictionary server), which means remote dictionary server, can reach 15w qps on a single machine. It is suitable for caching and persistence. ③ Redis is a high-p ...

When it comes to the concept of cache, I think everyone should be familiar with it. Cache applications represented by Redis and Memcache have basically become the standard configuration of microservice architecture. In fact, it does not mean that Redis and other services must be deployed to use cache. For example, in small single applications ...

Introduction to Redis database As a mature data storage middleware, Redis provides perfect data management functions, such as data expiration mentioned earlier and the data evict strategy we want to talk about today. Data locality principle The principle of locality, which runs through computer science, can clearly tell you that there are ...

mybatis cache mechanism I mybatis provides cache support, which is divided into L1 cache and L2 cache L1 cache The first level cache is enabled by default in mybatis. It is a cache form with hashMap as the data structure. How do I verify the L1 cache? The following example queries the same data twice (or multiple times, twice is ...

In many scenarios, the zookeeper cluster is used. For example, it uses its consistency ability and node monitoring ability to realize a variety of business functions.The problem encountered this time is that the zookeeper disk util is too high.First view the await index and util index of the disk through iostat, as shown in the following figure ...

1. Problem Description: Concurrent lrucache is used as the JVM cache pool object public class UserManager { private ConcurrentLruCache<UserCacheKey, UserInfo> cache = new ConcurrentLruCache<UserCacheKey, UserInfo>(100, new Function<UserCacheKey, UserInfo>() { @Override public UserInfo apply(UserCacheK ...

  1. Import dependent packages of Redisson and StringRedisTemplate <!--redisson rely on--> <dependency> <groupId>org.redisson</groupId> <artifactId>redisson</artifactId> <version>2.2.13</version> </dependency> <!--StringRedisTemplate rely on--> <dependency> ...

1, Basic introduction 1. Basic introduction Hash table (also known as hash table) is a data structure that is accessed directly according to the Key value. In other words, it accesses records by mapping key values to a position in the table to speed up the search. This mapping function is called hash function, and the array storing records is ...

catalogue Application scenario: Basic principle: Implementation method 1: Using redis as distributed lock Implementation mode 2: Using redistribution as a distributed lock Application scenario: In current distributed applications, there are often scenarios where high concurrent traffic accesses db. In order to prevent the database from ...