• Basis of redis: basic introduction, application scenario of redis, five data types, persistent operation, master-slave mode


    1、 Introduction to basic concepts and features of redis 1.1 introduction to basic concepts of Redis      1. Redis is remote, with client and server. We generally say server; 2.Redis isMemory basedYes, so it’s much faster than MySQL based on hard disk, but it’s very memory hungry 3. Redis is a non relational database. In […]

  • Type of LVM logical volume


    There are many types of logical volumes that can be created in LVM volume groups. The following describes different types of logical volumes Linear volume Linear volumes aggregate space from one or more physical volumes into a logical volume. Physical storage is linearly connected. Creating a linear volume sequentially assigns a series of physical extents […]

  • LVM logical volume management operation guide


    This paper introduces the common operations of managing LVM logical volumes Create LVM logical volume Use pvcreate to mark three disks as LVM physical volumes $ pvcreate /dev/sda1 /dev/sdb1 /dev/adc1 Make LVM physical volumes into volume groups called myg, and use the VGS command to view the status $ vgcreate myvg /dev/sda1 /dev/sdb1 /dev/sdc1 Create […]

  • Implementation of undo redo for web application


    background Not long ago, I participated in the development of a web application in the team, and one of the page operations is shown in the following figure: There is a PPT like interaction between the production pages: select elements from the toolbar on the left to put them into the middle canvas, delete them […]

  • Managing storage configuration with stratis


    Introduction to stratis Stratis is a local management storage solution for integrated management of complex storage configurations. Used to simplify storage configuration initialization and take full advantage of advanced storage features. The core concept of stratis is storage pool, which is built on disk or partition and has the characteristics of file system snapshot, thin […]

  • What kind of rendering scheme does Ali need for the double 11 in 2020?


    Alimei’s Guide:The “metabolism” of front-end technology is obvious to all. The continuous development of new technology also promotes the expansion of front-end application scenarios, from web, weex to node.js to FAAS. We see the unchangeable part in the development, only the pursuit of better user experience is the unchangeable responsibility in the sustainable development of […]

  • Secret of node.js memory leak


    By giovanny Gongora Crazy technology house Original: https://nodesource.com/blog/m No reprint without permission For a long time, tracking the memory leak of node.js is a recurring topic, and people always want to know more about its complexity and reasons. Not all memory leaks are obvious. However, once we determine its pattern, we must look for correlations […]

  • A kind of Learning redis from scratch


    Preface The text has been included in my GitHub warehouse. Welcome to star: https://github.com/bin3923282The best time to plant a tree is ten years ago, followed by now I know a lot of people don’t playqqYes, but in retrospect, welcome to join the six pulse magic sword Java rookie learning group, group chat number:549684836Encourage people to […]

  • Learning records of mongodb master class (day 18)


    Eighteenth days The chapter to be learned today is “21 transaction development: read operation transaction II”. Continue with yesterday’s topic. Yesterday, we talked about where to read the readpreference, and today, we talked about what kind of data readconcert to read. What is readconcert? After the specified node is selected by readpreference, readconcert determines which […]

  • [4. Distributed computing] Flink


    Flink has the computing functions of batch processing and stream processing, in which batch processing is simulated by stream computing. For more data processing, see https://segmentfault.com/a/11, distributed deployment; computing related parallel mode, stream processing time window, fault-tolerant processing, incremental computing, etc.Official: https://flink.apache.org Logical structure Deployment framework Standalonejob manager(master)+wokers Yarn based deployment Ha: Job Manager single […]

  • Rax PWA – quickly upgrade the web experience


    Rax PWA – quickly upgrade the web experience Rax PWA, a rax 1. X-based PWA solution. It is easy to build a full-featured PWA through simple configuration, providing users with web applications comparable to the native app experience. With the increase of mobile users, it is very important to optimize the user experience on mobile […]

  • Apache Flink zero foundation Introduction (1): basic concept analysis


    Author: Chen Shouyuan, Dai Zili 1、 The definition, architecture and principle of Apache Flink Apache Flink is a distributed big data processing engine, which can calculate the finite data flow and infinite data flow with or without state. It can be deployed in various cluster environments, and can calculate the data of various sizes quickly. […]