Tag:kernel

  • Basic knowledge of Linux back end programmer

    Time:2021-1-4

    Starting from understanding the operating system Before the official start of Linux, simply spend a little space on the content related to the operating system. 1.1. Introduction of operating system What is an operating system Operating system (OS) is the program to manage computer hardware and software resources, is the cornerstone of the computer. Operating […]

  • Linux basic knowledge for back end programmers

    Time:2021-1-3

    Starting from understanding the operating system Before the official start of Linux, simply spend a little space on the content related to the operating system. 1.1. Introduction of operating system What is an operating system Operating system (OS) is the program to manage computer hardware and software resources, is the cornerstone of the computer. Operating […]

  • Nginx learning architecture

    Time:2020-12-30

    Source: http://blog.seclibs.com/nginx… The program architecture of nginx is as follows Later, we will comb the architecture of nginx according to the content shown in this figure. The content involved in this paper is mainly for Linux system. The top master process is directly controlled by the administrator, and only the master receives the administrator’s signal. […]

  • Download and compile Android source code

    Time:2020-12-28

    Android source code download and compilation – 2020 use https://mirrors.tuna.tsinghua.edu.cn/help/AOSP Download the Android source code Repo 1 Download repo from Tsinghua mirror curl https://mirrors.tuna.tsinghua.edu.cn/git/git-repo -o repo chmod +x repo Set update source: export REPO_URL=’https://mirrors.tuna.tsinghua.edu.cn/git/git-repo/’ 2. Download Android Because the Android source code is bigger and bigger, the probability of repo sync failure is higher and […]

  • Super detailed analysis of bootloader to kernel boot process

    Time:2020-12-20

    @ catalog Analysis of bootloader startup process Bootloader phase 1 features Hardware device initialization Preparing RAM space for loading bootloader’s second phase code (initializing memory space) Copy the second stage code of bootloader into SDRAM space (relocation) Set up the stack Jump to the C entry point of the second stage code Functions of bootloader […]

  • Linux file IO panoramic analysis

    Time:2020-12-11

    This paper describes the following: Hierarchical view of file system How is the data organized on the hard disk? When reading and writing a file, how to address the disk sector from the beginning of the file? Complete process in read and write kernel Directio does not go through pagecache, and the user mode data […]

  • High performance IO zero copy

    Time:2020-12-10

    User space and kernel space Traditional IO stream Zero copy The main task of zero copy is to prevent the CPU from copying data from block storage to other block storage. The main task is to use various copying technologies to avoid making CPU do a large amount of data copying task, reduce unnecessary copying, […]

  • Actual combat: Linux method to prohibit and enable Ping

    Time:2020-12-8

    This document introduces the method of forbidding and opening Ping in rhel7 1、 Kernel parameter setting 1. Allow Ping settings temporary echo 0 >/proc/sys/net/ipv4/icmp_echo_ignore_all permanent echo net.ipv4.icmp_echo_ignore_all=0 >> /etc/sysctl.confSysctl – P ා execute thiscommandMake the changed / etc/ sysctl.conf Configuration file takes effect Note: if / etc/ sysctl.conf It already exists in the configuration file […]

  • Explain some important kernel files commonly used in RedHat system

    Time:2020-12-8

    In the network, many servers use Linux system. In order to further improve the performance of the server, it may be necessary to recompile the Linux kernel according to the specific hardware and requirements. To compile the Linux kernel, we need to follow the prescribed steps, and several important files are involved in the process […]

  • Simple sample sharing of compiling and installing CentOS kernel

    Time:2020-12-7

    Introduction to Linux kernelNow let’s take a look at the architecture of GNU / Linux operating system from a higher perspective. You can think of an operating system at two levels, as shown in the figure below At the top is the user (or application) space. This is where the user application is executed. Under […]

  • Source code interpretation of Linux kernel write time replication mechanism

    Time:2020-11-29

    Copy on write (cow) is an important mechanism of Linux kernel. We all know that when the parent process forks a child process, the child process and the parent process will share all private writable pages in a read-only manner. When one party is about to write, the cow page missing exception will occur. So […]

  • Record a docker build failure

    Time:2020-11-29

    Words are like meeting. Some time ago, Node.js The official release of node 8.9.3 lts version, and the home page of the official website indicates that the new version has important security updates, “important security releases, please update now!”, and then I immediately started to upgrade the node version of each module of the company’s […]