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What is the server? I believe that in addition to programmers, most people do not know much about it. Today, in order to let you know more about the server, I have summarized the following content. Let's take a look at it with the editor.

In a broad sense, a server refers to a computer system in a network that can provide some services to other machines. In a narrow sense, the server refers to some high-performance computers that can provide services through the network. Compared with the ordinary PC, the requirements of stability, security and performance are higher, so the hardware such as CPU, chipset, memory, disk system, network and so on are different from the ordinary PC.

As the node of the network, the server stores and processes 80% of the data and information on the network, so it is also called the soul of the network. Make a visual analogy: the server is like a post office switch, while fixed or mobile network terminals such as microcomputers, notebooks, PDA, mobile phones, such as telephones scattered in homes, various offices, public places, and so on. In our daily life and work, telephone communication and communication with the outside world must go through the exchange before we can reach the target telephone. similarly, network terminal devices, such as microcomputers in homes and enterprises, surf the Internet and obtain information. Communication and entertainment with the outside world must also go through the server, so it can also be said that the server is "organizing" and "leading" these devices.

The composition of the server is basically similar to that of the microcomputer, including processor, hard disk, memory, system bus and so on, which are specially designed for specific network applications. therefore, there are great differences between servers and microcomputers in terms of processing capacity, stability, reliability, security, scalability, manageability and so on. Especially with the progress of information technology, the role of the network is becoming more and more obvious, and the requirements for the data processing ability and security of your information system are getting higher and higher. if you are stolen by a hacker in the process of e-commerce, key business data will be lost If you cannot access the ATM properly, you should consider the behind-the-scenes commander of these equipment systems-the server, rather than complaining about the quality of the staff and other objective conditions.

At present, according to the architecture, servers are mainly divided into two categories:

Non-x86 servers: including mainframes, minicomputers and UNIX servers, which use RISC (reduced instruction set) or EPIC processors, and mainly use UNIX and other dedicated operating systems. The RISS processors mainly include IBM's POWER and PowerPC processors, the SPARC processors developed by SUN and Fujitsu, and EPIC processors developed by HP and Intel. This kind of server is expensive and the system is closed, but it has good stability and strong performance. it is mainly used in the core systems of large enterprises such as finance and telecommunications.

X86 server: also known as CISC (complex instruction set) architecture server, that is, PC server, which is based on PC architecture and uses Intel or other processor chips compatible with x86 instruction set and Windows operating system servers, such as IBM System x series servers, HP Proliant series servers and so on. Cheap, good compatibility, poor stability, unsafe, mainly used in small and medium-sized enterprises and non-critical business.

According to the theoretical definition, the server is a high-performance computer in the network environment, which listens to the service requests submitted by other computers (clients) on the network and provides the corresponding services. To this end, the server must have the ability to undertake service and ensure the quality of service.

But the explanation in this way is still more esoteric and vague. in fact, the function of the server is similar to that of the personal computer, both are tools to help people process information, but the positioning of the two is different. The personal computer (referred to as Personal Computer,PC for short) is designed to meet the multi-functional needs of individuals, while the server is designed to meet the needs of many users to process data on it at the same time. How can multiple people use the same server at the same time? This can only be achieved through network interconnection to help achieve this goal of common use. Let's take a look at the function of the server, the server can be used to build web services (the data of web pages we usually see on the Internet are stored on the server for access), mail services (all e-mails we send need to be processed, sent and received by the server), file sharing & print sharing services, database services, etc. And all these applications have a common feature, they are not for one person, but for a large number of people, while dealing with a large number of data. So the server and the network are inseparable. It can be said that without the network, there will be no server; the server is born to provide services, and it has the value of existence only in the network environment. The personal computer can complete the master's data processing task in the case of a single computer.

Hardware composition of the server:

In fact, there are many similarities between the hardware composition of the server system and the computers we usually come into contact with. the main hardware composition still consists of the following main parts: CPU, memory, chipset, Imax O bus, Imax O device, power supply, chassis and related software. This has also become the main indicator that we pay attention to when we choose and buy a server.

The whole server system is like a person, the processor is the brain of the server, and the various buses are like nerves distributed in the muscles of the whole body, and the chipset is like the spinal cord. I-peg O devices are like hands, eyes, ears and mouth that are innervated by the nervous system, while the power system is like a blood circulatory system, which sends energy to all parts of the body.

For a server, the performance design goal of the server is how to balance the performance of each part and optimize the performance of the whole system. If a server has the ability to handle 1000 service requests per second, but the network card can only accept 200 requests, while the hard disk can only handle 150 requests, and the load capacity of various buses can only handle 100 requests per second, then the server has to handle only 100 requests per second, and more than 80% of the processor's computing power is wasted.

Therefore, the ultimate goal of designing a good server is to make each part cooperate properly and give full play to its ability by balancing the performance of all aspects. We can measure whether the server has achieved its design purpose from these aspects: RRV ReliabilityMutti-reliability; AvailabilitywayAvailabilitywayAvailabilitywayusability-usability; usefulness-ease of use; and RASUM manageability-manageability, that is, the RASUM metric of the server.

As the server provides services in the network, the quality of this service is very important to the network computing environment that undertakes a variety of applications, and the computer hardware that undertakes this service must be able to guarantee the quality of service. First of all, this service must have a certain capacity and be able to respond to a reasonable number of server requests per unit time. At the same time, the response time of this service to a single service request should be as fast as possible, and this service should always exist within the required time range.

If a WEB server can only process one home page request in one minute, other requests than one must be queued up, and this request must be processed in 3 minutes, and this WEB server can be accessed an hour ago, but cannot connect an hour later. This kind of WEB server is unimaginable in today's Internet computing environment.

The current WEB server must be able to handle thousands of visits at the same time, while the response time of each access should be short, and the WEB server can not be down, otherwise the WEB server will cause the loss of visiting users.

In order to meet the above requirements, the server hardware must have the following characteristics: performance, so that the server can handle a considerable number of server requests per unit time and ensure the response time of each service; reliability, so that the server can not stop; scalability, so that the server can continuously improve the performance with the increase of the number of users. So we say that we can't use an ordinary PC as a server, because PC is far from meeting the above requirements. In this way, we add another point to the concept of the server, that is, the server must have the ability to undertake the service and ensure the quality of service. This is also the main aspect that distinguishes low-cost servers from PC.

In the information system, the server is mainly used in database and Web services, while PC is mainly used in desktop computing and network terminals. the difference in the fundamental starting point of the design determines that the server should have more reliable continuous operation capacity, stronger storage capacity and network communication capacity, faster fault recovery function and broader expansion space than PC. Applications that are sensitive to data also require the server to provide data backup function. On the other hand, the design of PC pays more attention to the ease of use of man-machine interface, image and 3D processing ability and other multimedia performance.

After reading the above, do you have a general understanding of the server? If you want to know more about the content of the article, welcome to follow the industry information channel, thank you for reading!

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