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Linux disk managementLinux disk management is directly related to the performance of the whole system.The three commands commonly used in Linux disk management are df, du, and fdisk.df (full English Name: disk full): lists the overall disk usage of the file systemdu (full English Name: disk used): check the disk space usagefdisk: used for disk ...

This article is an original article of Joshua 317. Please note: reprinted from Joshua 317 blog https://www.joshua317.com/article/203 One Linux command a day (43): netstat command 1, Introduction The netstat command under Linux is used to display various network related information, such as network connection, routing table, interface statistic ...

Orika preface There are many class replication tools, such as mapstruct, spring bean utils, Apache bean utils, dozer, etc. at present, mapstruct is used in my project team. In terms of performance, mapstruct is undoubtedly the best, because mapstruct copies attribute values through getter and setter methods, while other frameworks use reflectio ...

In the last article, we successfully built RabbitMQ on the server, which is equivalent to the red box in the middle. If you want to use RabbitMQ, you must also use two roles - Produces and Consumer, so let's specifically implement RabbitMQ to send and receive messages. 1. Working mode RabbitMQ provides six working modes for different sce ...

ConsumeQueue for source code analysis When sending a message, the data is displayed in the ConsumeQueue Five messages are sent continuously. The messages are of variable length. First, all information is put into the Commitlog. Each message needs to be locked when it is put into the Commitlog to ensure sequential writing. ​ After the Comm ...

Construction of ecological environment of Hadoop 3 Apache platform System environment The server: hadoop0,hadoop1,hadoop2 Operating system: CentOS 7.6 Software list and version: - jdk-8u202-linux-x64 - hadoop-3.2.28. - zookeeper-3.4.10 - afka_2.12-2.7.11 - spark-3.1.2-bin-hadoop3.2 - MySQL-5.1.72-1.glibc23.x86_64.rpm-bundle - hba ...

SSM integration Bili Bili crazy God says Java learning website The article is only for sharing learning experience and reviewing. It is more effective to check the formal video website and official documents Make a book query project using SSM framework Simple core axis of the project The eclips e development tool I use may be differen ...

Begin August 19, 2018 19:44:25Simple factory modedefinition As long as you say, as long as I have, I'll give it to you. Simple Factory Pattern: also known as static factory method (Static Factory Method) mode. Design modes are divided into creation mode, structure mode and behavior mode. Simple factory mode belongs to creation mode. In simple ...

MySQL Learning Notes Log on and exit MySQL server # Log in to MySQL $ mysql -u root -p12345612 # Exit MySQL database server exit; Basic Grammar -- Show all databases show databases; -- Create a database CREATE DATABASE test; -- Switch database use test; -- Show all tables in the database show tables; -- Create Data Table CREATE TABLE ...

preface When we want to share logic between two functions, we extract it into the third function. Both components and hooks are functions, so this method is also applicable. What are hooks and how to use them. Recommended articles: How to use react hooks? Play with react hooks, customize hooks design pattern and its actual combat rule Hook ...