• Learn JVM performance optimization


    Operational performance optimization 1 re recognize the JVM We have drawn a picture before, which is the process from class file to class loader, and then to runtime data area. Now we can enrich and perfect this picture to show the general physical structure of JVM.   Execution engine: used to execute JVM bytecode instructions […]

  • MySQL – InnoDB features – buffer pool


    Cache management is the core system of DBMS, which is used to manage the access, cleaning and expulsion of data pages. Although the operating system itself has page cache, it is not specially designed for the database, so most database systems manage the cache by themselves. Almost all data page accesses involve buffer pool, so […]

  • The foundation of Java multithreading programming — thread class


    thread When we read the program, it seems that we are tracking the processing flow of the program, but in fact, we are tracking the execution of the thread. Single threaded program In a single threaded program, there is only one process executed at a certain point in time. When a java program is executed, […]

  • [summary of JVM knowledge system framework]


    JVM memory distribution Thread shared data area:Method area – > class information, static variableHeap – > array object Thread isolation areaVirtual machine stack – > methodLocal method stack – > local method library native Heap, program counter JVM run data Program counter Thread isolation, relatively small memory space, line number of bytecode executed by current […]

  • Source code analysis of start and stop of spring boot + Dubbo application


    Background introductionDubbo spring boot project aims to simplify the development of Dubbo RPC framework in spring boot application scenarios. It also integrates the spring boot feature: Automatic assembly (e.g. annotation driven, automatic assembly, etc.) Production ready (e.g. safety, health check, external configuration, etc.) Dubboconsumer start analysis Have you ever thought about a question? The dubboconsumerdemo […]

  • This time, really understand the process and thread


    Introduction As a software engineer, process and thread should be our necessary knowledge, which can be seen from the interview questions of major enterprises every year! The difference between process and thread This semester, I learned the course of operating system, and the biggest achievement is that I learned the “must test”. At the beginning, […]

  • From simple to highly concurrent server (1)


    A single threaded echo server Let’s start with a simple server.It can take a customer’s connection, receive a message, send it back, close the connection – done. We use BSD socket, which is common on Linux and IOS / OSX, to write the code of this server. The main part is as follows: (c + […]

  • C × 8 – using declaration and asynchronous flow


    These two themes have nothing to do with each other, but I’m afraid that the home page will be removed if the article is too short. Using statement usingStatement block  although.NET CoreGarbage collector at runtime(GC)To be responsible for memory cleaning, but we still need to make sure that unmanaged resources should be cleaned up when […]

  • Async is not multithreaded


    Async is not multithreaded   Misunderstanding Async When debugging the xxxasync() method, we often see that there will be more threads in the debugger interface. Intuitively, we mistakenly think that the function named async is multithreaded This is true for the readasync() method in stringreader, Readasync () internally calls task. Fromresult (), which is Microsoft’s […]

  • Concept arrangement of Python process / thread


    Concurrent and parallel processes and threads Processes and threads First of all, we need to understand that our software runs on the operating system, and then the operating system controls the hardware, such as processors, memory, IO devices, etc. The operating system abstracts the concept of process in order to provide a simple and consistent […]

  • 6. Multithreaded singleton mode


          The original singleton mode is no longer applicable in multithreaded environment, so what should I do? Answer: (1) single instance mode of thread safety with double locking     (2) static initialization singleton mode     Direct instantiationSingletonObject inGetInstanceMethod_Instanceobject   We know that static members are initialized only once, that is to […]

  • Service of four Android components


    Preface Hi, Hello everyone. In the last issue, we talked about how to use the broadcastreceiver. In this issue, we talked about the service related knowledge of the four components of Android. Every day a technical dry goods, every day we progress together. Patience and concentration are not only virtues, but also wealth.   1. […]