Five basic server problems that must be understood

: This article mainly introduces five basic server problems that must be understood. For more information about PHP tutorials, see. Today we are talking about several questions about the basic server knowledge, which are also some common questions that are confusing the "Cainiao" who are beginning to be involved in the server field:

Is dual-channel 1 equal to dual-core?

Q: I often hear that dual-channel Xeon XX type server has recently appeared dual-core Xeon, both of which are two CPUs. is dual-channel equal to dual-core?

Answer: no

Regardless of the server's single, dual, quad, or even eight paths, the "path" indicates the number of physical CPUs of the server, that is, the number of CPU slots on the server motherboard.

Recently, a dual-core processor encapsulates two CPU cores in one physical CPU. the advantage is that it enables users to enjoy stronger performance without increasing the cost. In addition, it can significantly reduce the performance and power consumption ratio, which also has positive significance for enterprise users to save costs.

2. difference between Xeon and Pentium

Problem: In many servers, Xeon processors and Pentium 4 processors are used as processors. in addition to the Pentium 4 processor, the server products are cheaper, what is the difference between Xeon and Pentium?

Intel Pentium 4 631 3.0 GHz (box)

Intel Xeon 3.2G (800 ** z/2 M/box)

Answer: The Xeon processor used on the server is basically the same as the ordinary P4 processor.

One of the differences is that, starting with Intel Pentium 4 processor, the Pentium 4 processor is classified as a personal processor. users cannot build 2-way server systems with 2 Pentium 4 processors, A Xeon processor with higher computing efficiency is developed. Currently, Xeon processors are divided into Xeon DP (dual-channel processing is supported) and Xeon MP (up to 8-channel processing is supported ).

The second difference is that the second-level cache is different. The second-level cache of Xeon is 1 MB ~ 16 MB, P4 second-level cache is KB ~ 1 MB, and the second-level cache capacity is also an important factor that determines the server processing efficiency.

The Xeon series CPU is mostly 604 interfaces, while the P4 CPU is mostly 478-pin or 775-core.

Note: In X86 architecture, in addition to Intel Pentium and Xeon series processors, AMD also provides a dedicated processor-Haolong Opteron, which can support up to 8 channels.

AMD Opteron Haolong 865 (scattered)

3. Several server types

Q: What types of servers are divided by structure?

Answer: According to the shape structure, servers can be divided into three types: Tower, rack, and blade.

Tower Server

The general Tower server chassis is similar to the commonly used PC chassis, while the large tower chassis is much larger. In general, there is no fixed standard shape size.

Rack Server

Rack servers are Server types with 19 inch racks as the standard width due to the intensive deployment of enterprises. The height ranges from 1U to several U. Placing servers on racks is not only conducive to routine maintenance and management, but also may avoid unexpected faults. First, server placement does not occupy too much space. Rack servers are neatly discharged from the rack without wasting space. Second, the connection lines can also be neatly stored in the rack. Cables such as power cables and LAN cables can be laid in the cabinet to reduce the number of cables stacked on the ground to prevent accidents such as power cables being kicked off. The specified size is the server width (48.26 = 19 inch) and height (multiples of 445cm ). Because the width is 19 inch, the rack meeting this requirement is sometimes called "19 inch rack ".

Blade servers

The blade server is a low-cost server platform with High Availability (High Availability and High Density). It is specially designed for the extraordinary application industry and High-Density computer environments, each "Blade" is actually a system motherboard, similar to an independent server. In this mode, each motherboard runs its own system and serves different user groups. However, you can use system software to assemble these boards into a server cluster. In cluster mode, all master boards can be connected to provide a high-speed network environment, and resources can be shared to serve the same user group.

4 What is "U?

Q: What does "U" in a 1U or 2U server mean? Does it mean the number of server processors?

Answer: in the server field, "U" refers to the thickness of a rack-mounted server. it is a unit that represents the external size of the server. it is the abbreviation of unit, the specific dimensions are determined by the American Electronics Industry Association (EIA), which serves as an industry group. The reason for specifying the server size is to keep the server in proper size so that it can be placed on an iron or aluminum rack. There is a fixed server nut on the rack, which is aligned with the server's nut and fixed with screws. The thickness is the basic unit of 445cm. 1U is 4.445, and 2U is 2 times of 1U is 8.89. That is to say, the so-called "1U rack server" is a product that meets the EIA specifications and has a thickness of 4. 445cm.

5 What is the difference between a server and a workstation?

Q: What is the difference between a server and a workstation?

Servers provide various services to workstations, such as network communication services, file sharing services, hardware sharing services, and various resource services. The workstation can also help the server to distribute computing tasks while obtaining various server resources.

Servers and workstations are high-performance computers, but servers focus on data throughput, so more peripherals (hard disks, I/O slots, etc.) are supported; the workstation focuses on the graphics processing capability, so there are relatively few peripherals, but it adopts an extraordinary architecture designed for graphics processing and uses high-end display cards to support 3D image processing. Workstation is mainly used in various design and multimedia production fields.

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The above describes the five basic server issues that must be understood, including the content, and hope to be helpful to friends who are interested in the PHP Tutorial.