scholl concepts

query Rate per second QPS: a measure of how much traffic is handled by a particular query server over a specified time, that is, the number of requests per second, which is the maximum ability to talk.concurrency number: concurrency and QPS are different concepts, generally say that the QPS will say how many concurrent users under the QPS, when the QPS, the greater the number of concurrent users, the better the site concurrency processing power. When

Lau!This real-world example is the same as we do in development, where we create a proxy object for an object that is primarily used to intercept access to real business objects. So what should be the method of the proxy object? The proxy object should have the same method as the target objectSo here are two concepts that explicitly represent the proxy object:1. The value of proxy object is mainly used to intercept access to real business objects .2.

AopWhat is it? AOP is functionally a function of doing some business logic before and after you can allow you to dynamically add some operations (such as logging, or to determine whether there are permissions, etc.), the addition of these operations is completely decoupled from the original business logic, so that the original business logic is completely transparent.In other words, this operation is completely separate from the business logic, which may require the crosscutting of multiple modu

Spring AOP Basic Concepts Directory Spring AOP Definition Basic terminology for AOP Notification type AOP defines AOP basic terminology Facets ( Aspect ): A modular focus that can cross-cut multiple objects. For spring AOP, facets are ordinary classes (schema-based) or classes that use @Aspect annotations. Joint Point: A point in the course of a program's execution. For spring AOP, the connection point

list elements, can generate child rows for placing child elements.There are three situations that will cause elements to flow out of the document, floating, absolute positioning, fixed positioning. But floating elements in IE also exist in the flow of documents (which makes me feel reasonable >Floating elements do not account for any normal flow of documents, and the positioning of floating elements is based on a normal flow of documents, then extracted from the document stream and moved as far

The previous section learned and practiced the foundation and installation of Docker, and this section mainly studies the main concepts and commands of Docker Docker has three core concepts: Mirroring, container, warehouse one, mirroring Docker mirroring is a precondition for running a container, and if there is no mirror locally, Docker will attempt to download from the default Mirror warehouse (Docker hub

Objective Contact game development time is not long, has been writing Lua, writing Lua is certainly no development, at least you will write. Write the client, must see Cocos2d-x. From today onwards, officially began to cocos2d-x learning journey. has been doing the development of C + +, turned to see Cocos2d-x, from the language, there are not many problems. For me, Cocos2d-x is a class library, similar to MFC, ATL and Qt, is a game class library, and I follow the Learning class library using

between them. Specifically, for time-sharing operating system, software implementation in time requirements, not strict, time errors, generally will not cause disastrous consequences. For real-time operating systems, the main task is to deal with the event in real time, although the event may arrive at an unpredictable time, but the software must be able to respond to the event in a strict time frame within the time of the response (System response times), even under the peak load, it should be

Using ASP.net 2.0 technology, creating Web custom server controls is not an easy task. This requires developers to understand and have the flexibility to apply a variety of web development technologies, such as CSS style sheets, client-side scripting languages, and. NET development language, server control development technology, even the current most fire Ajax technology, and so on. Although the reality is so "difficult", but this kind of development technology is not really difficult to master

Data structure basic concepts and terminology: bit, byte, word, bit string, element, data field, physical structure, logical structure Bit: "Bit" is the smallest unit of data in the computer. The state of each bit can only be 0 or 1. Bytes (byte): 8 bits constitute 1 bytes (byte), which is the basic unit of measurement for storage space. 1 bytes can store 1 English letters or half Chinese characters, in other words, 1 Chinese characters occupy 2 by

The first blog post, we have a simple understanding of zookeeper, and more obvious, easy to understand, this blog, we understand its basic concepts, as shown in the following figure: Understanding its basic concepts helps us learn later, although today's articles are conceptual in nature, but significant. one, cluster role: Zookeeper clusters usually have three roles: Leader,follower,observer.

Ivy introduced some of its own concepts to understand and ignore these concepts for Ivy's learning to use is helpful. Here translation of the official website of the main concept of Ivy article, the original text in this: http://ant.apache.org/ivy/history/2.1.0-rc1/concept.html Split because the content is too long, here is the second part: Six. Conflict Manager The conflict Manager can select the revisi

To understand the application development process, first understand some of the key concepts that Visual Basic relies on to create. Because Visual Basic is a Windows development language, it is necessary to maintain a certain similarity to the Windows environment. If you are unfamiliar with Windows programming, you need to understand some of the fundamental differences between programming in a Windows environment and programming in other environments.

Summary: The Java Message Service (JMS) API is a messaging standard, allows application components based on the Java platfor M Enterprise Edition (Java EE) to create, send, receive, and read messages. IT enables distributed communication is loosely coupled, reliable, and asynchronous. The JMS (JAVA message Service,java message Service) API is a standard or specification for a messaging service that allows application components to create, send, receive, and read messages based on the Java EE pla

Ethereum client (Go language implementation) With some basic commands of Geth, it is easy to create a private chain of ethereum. Geth--datadir "./" init Genesis.json geth--datadir "./"--nodiscover console 2>>geth.log Geth's command line contains most of the Ethereum commands, including the new account, the transfer of the etheric currency between accounts, the mining, the balance, the deployment of the Ethereum contract, etc. Of course, the shortcomings of Geth is also obvious, geth or the unde

PS: The following are the main concepts and calculation formulas for performance testing, which are documented below: A System Swallow metric elements: The Swallow metric (pressure capability) of a system is closely associated with the request for CPU consumption, external interfaces, Io, and so on. The higher the CPU consumption of a single reqeust, the slower the external system interface and IO effect, the lower the system throughput capacity, and

are a thing or an object that can be distinguished from other objects in the real world.E-R provides a convenient graphical way to observe data, relationships, and constraints.The entities in the database are described by the set of attributes (attribute);Contact (relationship) is the association between several entities;A collection of all entities of the same type is called an entity set, and the collection of all contacts of the same type is called the contact set (relationship set);Object-b

indexes can be created in the following ways: Create indexes, such as the name of the CREATE INDEX Uniqueness IndexThis index is basically the same as the previous "normal index", but there is one difference: all the values of an indexed column can only occur once, that is, they must be unique. A unique index can be created in the following ways: Create indexes such as the name of the Create UNIQUE Index Primary keyA primary key is a uniqu

Basic ConceptsTo understand the paradigm, you first have to know what a relational database is, and if you don't, I can simply not simply say that a relational database uses a two-dimensional table to hold data. Between table and table can ... (Omit 10W words).Then you should understand the following concepts: things that exist in the real world and can be distinguished. such as "A student", "a book", "a course" and so on. It is worth empha

system Throughput (TPS), user concurrency, performance test concepts and formulasPosted in: DataBase, Linux, UNIX, Windows, Personal diary | Author: a Global person A System Swallow metric elements: The Swallow metric (pressure capability) of a system is closely associated with the request for CPU consumption, external interfaces, Io, and so on. The higher the CPU consumption of a single reqeust, the slower the external system interface and IO eff