how opendns works

Ajax works by adding an intermediate layer between the user and the server , which causes the user operation to be asynchronous with the server response . In this way, some of the previous workload of the server is passed on to the client, which is advantageous to the client's idle processing ability to deal with, reduce the burden of server and bandwidth, so as to save ISP 's space and bandwidth leasing cost . by simply speaking The XMLHttpRequest

HTML5 is now a hotspot in web development, and more developers are starting to use HTML5 to develop interactive, effective web applications and games. Today, this article collects 15 exquisite HTML5 single page website works, lets everybody feel the HTML5 charm, together appreciates. Digitalhands Hellocarbon Morehazards Bokicabo Mindepic Tejpotter Unfold

? 1 2 3 4 5 6 7 The above example seems simple, but the results are not well understood, it is easy to get people to think about it-"a.x is not pointing to object a?" Why is log (a.x) undefined? "," b.x should not be the same as a.x? Why does log come out with 2 objects? Of course, you can first understand, if you can see the reason and working mechanism naturally need not continue to look down. The following is an analysis of the working steps of this simple

recently, ONOS Community and Linux Foundation jointly announced a strategic partnership, the two sides will jointly develop open source SDN/NFV solution. The ONOS project works with the Linux Foundation to create disruptive SDN solutions that focus on open source platforms, white boxes, a range of network control and management applications, and the ability to quickly create and deploy innovative services for service providers to achieve SDN/NFV econo

How the Linux kernel analyzes how the operating system works20122137 Sha Yu JiOriginal works reproduced please indicate the sourceLinux kernel Analysis MOOC course http://mooc.study.163.com/course/USTC-10000290001. Content DescriptionThe inline assembly syntax is as follows:The specific code is as follows:(1) Mypcb.h header file/** Linux/mykernel/mypcb.h* Kernel Internal PCB types* Copyright (C) mengning*/#define MAX_TASK_NUM 4#define Kernel_stack_siz

Original how TCP backlog works in LinuxThe level is limited, inevitably mistake, welcome to point out!The following are translations:When an application listen a socket (socket) to the listen state through a system call, a backlog parameter is specified for the socket, which is typically described as the length of the connection queue to limit incoming (queue of incoming connections).Because of the three-time handshake mechanism of the TCP protocol, a

Fan Original works reproduced please specify the source "Linux kernel Analysis" MOOC course http://mooc.study.163.com/course/USTC-1000029000According to the experimental requirements, the operation in the experimental building.Time Slice Rotation method(Enter VI main.c to view Mykernel source code)The most core code in MYMAIN.C(myinterrupt.c code, each time the clock interrupts the call once PRINTK)2. Operating system Kernel source code "analysis See

How the computer worksThree Magic Weapon: Store program computer, function call stack, interrupt mechanism.StackFunction call FrameworkPassing parametersSave return addressProvides local variable spaceStack-related registersESP stacking pointer (stack pointer)EBP base point pointer (base pointer)Stack operationsPush;popEBP serves as a record of the current function call base-Other key registersInterruptCall command: 1, the EIP of the next instruction to save the address a at the top of the stack

Name: Wang ChenguangStudy No.: 20133232Wang Chenguang + original works reproduced please specify the source + "Linux kernel analysis" MOOC course http://mooc.study.163.com/course/USTC-1000029000First, the process of starting and switching source code and analysistypedef struct PCBs are used to represent a process that defines a process-management-related data structure. The data types used to hold the EIP and ESP are also set.The following code is par

many processes or fork several processes, and when interrupts occur, such as when a clock interrupt occurs in Mykernel, the OS then schedules the processes. Select a suitable process in the dispatch queue, which holds the registers information of the previous process by the CPU and the kernel stack (the thread structure in the process description block holds most of the CPU registers, but these general-purpose registers such as EAX, EBX, etc. are saved and stacked). The EIP points to the addres

Knowledge Points:Von Neumann architecture, its core idea is to store the program computer.The CPU is connected to the memory via the bus, and the IP pointer takes one instruction from the memory in turn.API: interface between programmer and computer.ABI: interface between program and CPU.Registers, addressing methods and various directives have been thoroughly understood in the study of "in-depth understanding of computers" and "compilation".Experiment:Into the following:The original code is:int

Linux kernel Analysis first week study summary-How the computer worksZhang Yi (Original works reproduced please specify the source)"Linux kernel Analysis" MOOC course http://mooc.study.163.com/course/USTC-1000029000I. working process of assembly Code1. Experimental processint A (int x) { return2int b (int x) { return int main (void) { return B (51 ;}The assembly code is as follows:2. Code AnalysisSecond, the process of computer workThe general

"Peace of Blessing + Original works reproduced please specify the source +" Linux kernel analysis "MOOC course http://mooc.study.163.com/course/USTC-1000029000 "first, the process of initializationThe operating system kernel boot entry function is void __init my_start_kernel (void);Here is a simple definition of the two CPU states of a process:struct Thread {unsigned long IP; Indicates an EIP directiveunsigned long sp;//represents ESP, stack top poin

(i) DescriptionA brief description of how Django works, with 2 examples.(ii) How Django worksSuppose we have the following files, here in the first 2 articles based on the addition of the templates directory (storing HTML files) and static directory (storage image JS, CSS, etc.)(iii) Implementation of a complete user interface# Suppose you've created a project and an app. The following urlconf and view functions have no relationship, according to thei

new technology, for the creation of fast Dynamic Web page technology. As a result, Ajax also has a fashionable term "facelift for a new makeover".2. Ajax includes:1. HTML for creating Web Forms2, DOM, for dynamic display and interaction3, XML, using XML to do data interaction and operation4, XMLHttpRequest, asynchronous data reception5. JavaScript, which binds them tightly togetherI believe you are familiar with the above technology, the most difficult is to create XMLHttpRequest objects, you s

. Why use a thread pool?We now consider the simplest server working model: The server creates a thread for its service whenever a client request is received. This mode works well in theory, but there are some drawbacks, and it is common in server applications that the task of single client request processing is simple but the number of clients is huge. Therefore, the time and system resources that the server spends creating and destroying threads can

Designers, engineers, architects, and other creative professionals spend most of their time in front of their computers. Almost all job completion, social relationships and e-mail communication are done in front of the computer. In fact, computers have become the main modern way of life, and people use more of these devices to make their jobs more efficient.Today, I would like to take your attention to 20 examples of web design with a clean working area in the background. Countless digital agenc

Most people know what the require () function does in node. js, but how many people know how it works? We use it every day to load library packages and modules, but its internal behavior is mysterious.We follow the core of the Node module system: Module.js, which contains a surprisingly magical feature that is responsible for loading compiling and caching each used file, let's uncover its mystery.function Module (ID, parent) { this.id = id; this.e

The function of Photoshop in the later production of photographic works Color Replacement Tool The color replacement tool is a very flexible and accurate color replacement tool. Operation, we just set the foreground color first, and set the relevant parameters such as mode, tolerance in the property bar, and then smear on the color block or image that needs to be replaced, the color will be replaced with the previous set of foreground colors. At the

First up Effect chart: It's very stylish, isn't it, eh, let's start now. Step 1 To create a new file, the parameters are as shown: Step 2 Create a new guide to balance the vision. Position: horizontal 60px, vertical respectively is 20px,,50px,115px,230px,550px,570px,875px and 1180px, here is recommended that schoolmates use the artifact "guideguide", the concrete use the work moves: PS Reference line plug-in guideguide download and use instructions, very convenient.