• Class loading problem caused by parallel flow in Tomcat application


    This article starts with vivo Internet technology WeChat public.Link: https://mp.weixin.qq.com/s/f-x3n9cvdyu5f5nyh6mhxqAuthor: Xiao Mingxuan, Wang daohuan With the popularity of Java 8, more and more developers use parallel to improve code execution efficiency. However, the author found that the use of parallel flow in Tomcat container would lead to the failure of dynamic loading of classes. By […]

  • Spring boot timing task, there is always one for you


    Preface Timed tasks can help us deal with tasks within a given time. For example, your alarm clock will teach you to get up every morning. For example, it will read your employment status in the company’s personnel list in the early morning of every day. If it is a resignation, it will automatically delete […]

  • High performance network communication framework netty basic concepts


    Abstract:Netty is a NiO framework that can easily and quickly develop protocol server and client network applications. It greatly simplifies the network programming of TCP or UDP server, but you can still access and use the underlying API. Netty just abstracts it at a high level. I. Preface Netty is a NiO framework that can […]

  • Kafka source code analysis 2: metadata cluster meta information


    Summary As mentioned in the previous sectionClusterIt is mainly used to store node information, topicpartitionpartition information and partitioninfo partition details. This section is aboutMetadataWill beClusterEncapsulation provides a unified query entry, and also provides the update operation of cluster information. Class annotation By readingMetadataThe following conclusions can be drawn from the notes: Metadata is shared by […]

  • Netty asynchronous future source code interpretation


    Address: https://juejin.im/post/5df771 Said ahead The netty source code of this article uses4.1.31.FinalVersion, different versions will have some differences JDK Future Before talking about the asynchronous future of JDK, I will briefly introduce the future mechanism of JDK First, the previous code public class JDKFuture { static ExecutorService executors = new ThreadPoolExecutor(1, 1, 60, TimeUnit.SECONDS, new […]

  • Wait notify notifyAll await signal


    Starting with a common interview question, the description of the question is as follows: There are three threads to print a, B and C respectively. Please use multithread programming to realize, print 10 times abcabc on the screen Most of the Internet has taught you how to implement it. In fact, I also wrote an […]

  • Create a wheel thread pool


    I’ve seen the source code of thread pool for a long time (I know the general operation principle), but I just know how to use it, and I didn’t go deep into it. In order to help me understand the thread pool in depth, I decided to write a simple (crude) thread pool manually and […]

  • Talking about progress and thread from Chrome browser


    Before we start talking about processes and threads, one of the first concepts we need to understand is parallel processing, because when you understand parallel processing, your understanding of processes and threads will be much easier. What is parallel processing Literally, parallel processing means processing multiple tasks at the same time. For example, we need […]

  • [TF. Keras] API changes from tensorflow 1. X to 2.0


    Tensorflow version 2.0 uses keras as a high-level API, which is very friendly for keras boy / girl. Tf.keras is migrating from version 1. X to version 2.0. Several changes are needed. 1. Set random seeds import tensorflow as tf # TF 1.x tf.set_random_seed(args.seed) # TF 2.0 tf.random.set_seed(args.seed) 2. Set the number of parallel threads […]

  • Interview spark module – spark workflow?


    Spark’s workflow? Answer train of thought All spark programs are inseparableProgram initializationandPerform tasksThese two parts, so the question can be answered from these two parts. Process of program initialization After the user submits the program through spark submit, the driver program starts to run (driver program is the submitted program running, which can be understood […]

  • Android process scheduling


    In Linux system, processes are divided into real-time processes and ordinary processes. The priority range of real-time processes is 0-99, and that of ordinary processes is 100-139. Moreover, the scheduling strategies of the two processes are also different. Android system is developed on the basis of Linux system, which makes full use of some features […]

  • Seriously, I found a mistake in this book!


    This article starts with the public number [why technology], pays attention to the public number, has a better typesetting way, and has a better reading experience. Hateful title party First of all, let me talk about the mistakes I found in the art of Java Concurrent Programming.The edition of the art of Java Concurrent Programming […]