【DKV】改變中的數(shù)據(jù)中心前景 (第一章)

yi321yi 2019-08-12

展開全文

Part1 Information Technology Equipment

第1部分信息技術設備

BY DONALD L. BEATY, P.E., FELLOW ASHRAE; DAVID QUIRK, P.E., MEMBER ASHRAE.

作者：DONALD L.BEATY 專業(yè)工程師、ASHRAE會員；DAVID QUIRK,專業(yè)工程師、ASHRAE會員。

譯者：何海

Information technology equipment (ITE) continues to evolve to keep pace with the rate of change of software and the feature-rich services they provide. The HVAC systems and their interactions with the ITE will also need to evolve. While the“occu-pant” of data center is the software, at its core, the ITE design dictates how that occupant load manifests itself within the data center. By understanding the ITE its changes, and how it interacts with the data center HVAC, data center designers will be equipped to handle this changing landscape.

信息技術設備(ITE)持續(xù)不斷發(fā)展，以適應軟件及其提供的豐富服務的演變速度。HVAC（暖通空調(diào)系統(tǒng)）和ITE的相互作用同樣需要轉(zhuǎn)變。當數(shù)據(jù)中心的“居住負載”是軟件時，ITE設計規(guī)定的核心是如何將居住負載體現(xiàn)在數(shù)據(jù)中心內(nèi)部。通過了解ITE的變化及其與數(shù)據(jù)中心暖通空調(diào)的相互作用，數(shù)據(jù)中心設計師將可以更好地應對這一變化的前景。

A tremendous variety of ITE populates today’s data centers, owing to the exponential growth of data generation, data storage, and data consumption that permeates our lives more each day. Traditional servers now cohabitate in the data center space with huge storage arrays and powerful supercomputing clusters, all with widely different workloads that stream our videos, maintain our homes, route our communications, predict our weather, and generally accomplish things previously thought not possible!

數(shù)據(jù)生成、數(shù)據(jù)存儲和數(shù)據(jù)消費已經(jīng)滲透到我們生活中的每一天，并呈指數(shù)級增長，因而如今的數(shù)據(jù)中心遍布各類不同的ITE?，F(xiàn)在，傳統(tǒng)的服務器在數(shù)據(jù)中心空間中擁有巨大的存儲陣列和強大的超算集群，所有這些服務器都扮演著各種不同的工作角色，如：視頻傳輸、家庭運行、通信路由、天氣預報，并且通?？梢酝瓿蓮那罢J為不可能完成的任務。

And yet, all of these things are accomplished by equipment in data centers, using similar resources and encountering similar challenges. Data may be just a seriesof1’s and0’s, but manipulating trillions of them consumes electricity, and lots of it. That electricity isdissipated in the form of heat, which itself must be dissipated, or the bulk of equipment would almost certainl yincinerate.

然而，所有這些都是通過在數(shù)據(jù)中心使用類似的資源和面臨相似挑戰(zhàn)的設備來實現(xiàn)的。數(shù)據(jù)可能只是一系列的“1”和“0”，但操縱數(shù)萬億的數(shù)據(jù)會消耗大量電能。電是以熱能的形式耗散的，散熱是必不可少的，否則大部分設備幾乎肯定會被燒毀。

This is Part1 in a series that will explore the current state of ITE in the data center, covering the different equipment types, thei rroles, and their general arrangement within the data center. This will not be comprehensive by any means, but rather serve to create a solid foundation from which to explore in more detail the changing landscape of data centers. 1 Future parts in this series will cover ITE thermal design and the interactions between IT systems and data center cooling systems.

本系列文章的第1部分將探討數(shù)據(jù)中心中ITE的現(xiàn)狀，包括不同的設備類型、它們的角色及其在數(shù)據(jù)中心中的常規(guī)布置。然而無論如何，這部分都不是全部內(nèi)容，而是為深入探索數(shù)據(jù)中心不斷變化的前景打下了堅實的基礎¹。本系列接下來的部分將介紹ITE熱設計以及IT系統(tǒng)和數(shù)據(jù)中心冷卻系統(tǒng)之間的相互影響。

Data Center Design

數(shù)據(jù)中心設計

Data center infrastructure designers are tasked with wrapping a shell, power, and cooling around ITE. To do this effectively, flexibly, efficiently, and in a scalable manner, we need to better understand how the ITE is designed, how it’s changing, and why it’s changing.

數(shù)據(jù)中心基礎設施設計師的任務是為ITE封裝外殼、提供電源和冷卻。為了以有效、靈活、高效、可擴展的方式實現(xiàn)這一點，我們需要更好地理解如何設計ITE、以及ITE是如何變化的、為什么會變化。

Historical data center design philosophy often considered the ITE as a homogenous load separated into aisles of equipment and arranged in hot/cold aisles for proper thermal management.2. The goal of the HVAC was to provide the proper entering air conditions to the ITE.3

歷史上，數(shù)據(jù)中心的設計理念通常是將ITE作為均勻的負荷分散到設備通道中，并安排在熱/冷通道中進行適當?shù)臒峁芾?sup>2。HVAC的目的是為ITE提供適當?shù)倪M風條件³。

Today’s ITE consists of several very distinct types of hardware (servers, networking, and storage), each with their own unique designs and functions for supporting different types of data and services. Each of these types of ITE will correspondingly interact with the data center infrastructure in different ways.

當今的ITE由幾種完全不同的硬件(服務器、網(wǎng)絡和存儲)組成，每種硬件都有自己獨特的設計和功能，用于支持不同類型的數(shù)據(jù)和服務。每種類型的ITE都將以不同的方式與數(shù)據(jù)中心基礎設施相互影響。

In generic terms the ITE is divided into these basic functions:

· Servers: data computing and processing;

· Networking: data transmission; and

· Storage: data storing.

一般情況下，ITE可以分為以下功能類型：

1. 服務器：數(shù)據(jù)計算和處理；

2. 網(wǎng)絡：數(shù)據(jù)傳輸；

3. 存儲：數(shù)據(jù)儲存。

In all cases, the use of data consumes energy and releases heat within the data center. The most efficient and effective management of that heat is dependent upon a more detailed understanding of the ITE design and its interactions with the data center infrastructure.

在所有情況下，數(shù)據(jù)的使用都會消耗能量，并在數(shù)據(jù)中心內(nèi)釋放熱量。最高效和有效的熱量管理依賴于更深入地理解ITE設計及其與數(shù)據(jù)中心基礎設施的相互影響。

Servers

服務器

In IT terms, “server” broadly refers to equipment that provides utility to a “client.” Servers not only provide the webpages and files that we are most familiar with, but more abstractly provide computational resources across networks to be consumed by services.

在IT術語中，“服務器”泛指為“客戶端”提供實用程序的設備。服務器不僅提供我們最熟悉的網(wǎng)頁和文件，還更抽象地提供跨網(wǎng)絡計算資源供服務使用。

The role of the server has grown immensely through the years to meet our demands, and, through specialization, servers may achieve higher degrees of throughput, speed, and energy efficiency. Therefore, the server design of yesterday is not the server design of today, and will not be the server design of tomorrow.

多年來，為滿足我們的需求，服務器的性能已大大增強，通過專門設計，服務器可以實現(xiàn)更高的吞吐量，速度和能效。因此，昨天的服務器設計不同于今天的服務器設計，也不同于明天的服務器設計。

The central processing unit (CPU) has traditionally been the heart of the server, supported by memory, storage, and other peripherals. A CPU consists of millions

or billions of individual switches that each produce heat as they operate billions of times per second. As such, they are one of the highes theat producing components within the server and a primary concern for cooling, accomplished by either air or liquid.

中央處理器(CPU)傳統(tǒng)上是服務器的核心，由內(nèi)存、存儲器和其他外圍設備支持。一個CPU由數(shù)百萬或數(shù)億個獨立的開關組成，每一個開關每秒運行數(shù)億次時都會產(chǎn)生熱量。因此，它們是服務器中產(chǎn)生熱量最高的器件之一，也是風冷和液冷的主要關注點。

The CPU is usually attached via a socket to a mother-board, whichprovides power to and interconnections between the components of the server located directly on the motherboard as well as other peripherals.

CPU通常通過一個插座連接到主板上，主板為主板上和其他外圍設備上的服務器組件提供電源和相互連接。

For CPUs to perform their function, they require memory to hold in the inputs and outputs, and it must be incredibly fast to keep up with the demands of the CPU. As a technical result, the memory closest to the CPU is volatile memory, or memory that does not retain its data without power, as this yields the highest performance. Static random-access memory (SRAM) is the fastest and is located on the same die as the CPU, whereas dynamic random-access memory (DRAM) is somewhat slower and typically located on memory chips near the CPU. Later, the important resulting data is written to non-volatile storage media, but at slower speeds.

為了讓CPU執(zhí)行它們的功能，它們需要內(nèi)存來保存輸入和輸出數(shù)據(jù)，而且必須足夠快才能滿足CPU的需求。從技術上講，在得到最高的性能同時，最接近CPU的內(nèi)存是易失性存儲器，它在失去電源的情況下無法保存數(shù)據(jù)。靜態(tài)隨機存取內(nèi)存(SRAM)是速度最快的內(nèi)存，集成在CPU內(nèi)部；動態(tài)隨機存取內(nèi)存(DRAM)稍微慢一些，通常位于CPU附近的內(nèi)存芯片上。稍后，重要的結(jié)果數(shù)據(jù)將以較慢的速度寫入非易失性存儲介質(zhì)。

Traditional types of non-volatile storage found in the data center include hard disk drives (HDD) and tapes, although solid state drives (SSD) are increasingly preva-lent due to their comparatively low latency and decreasing cost. SSDs use flash memory, a non-volatile form of memory that involves no moving components, unlike HDDs and tapes.4.

數(shù)據(jù)中心中傳統(tǒng)的非易失性存儲類型包括硬盤驅(qū)動器(HDD)和磁帶，然而固態(tài)硬盤(SSD)由于其相對較低的時延和成本而越來越受歡迎。SSD使用閃存，與HDD和磁帶不同，閃存是一種無運動器件的非易失性內(nèi)存形式⁴。

To increase server performance for some types of workloads, a current trend is using SSDs closer to the CPU via peripheral component interconnect express (PCIe) as their costs decrease and performance and capacity increase to where they offer attractive benefits compared to adding more DRAM.

為提高某些類型工作負載的服務器性能，當前的趨勢是使用SSD通過標準總線接口（PCIe）與CPU連接。與增加DRAM相比，SSD的成本更低，性能和容量更高，因而更具吸引力。

However, HDDs and tapes still play an important role in the data center. HDDs use magnetic storage on rotating disks and offer low cost and fast access, whereas tapes are significantly slower but can store data with unparalleled economy and are the only format to offer an archival-appropriate lifespan (e.g., 30 years).

然而，硬盤和磁帶在數(shù)據(jù)中心里依然扮演著重要角色。HDD使用機械磁盤上的磁存儲器，提供低成本和快速訪問，而磁帶速度非常慢，但可以非常經(jīng)濟地存儲數(shù)據(jù)，是唯一滿足檔案壽命(如30年)的存儲格式。

The most common form factor for servers is the 19 in. (483mm) wide rack-mount server. The design is a time-less standard defined by the EIA-310 specification5 that has filled the majority of the world’s data centers for decades. It is based on 1.75 in. (44.5mm) tall rack units(U), and equipment is specific as 1U,2U,4U,etc., referring to its height. Whilemost equipment makes full use of the width, half-width equipment is an increasingly popular alternative that offers potentially higher density per U.

服務器最常見的規(guī)格是19 英寸(483毫米)寬度的機架式服務器。該設計是一個由EIA-310規(guī)范⁵定義的永久標準，幾十年來世界上大多數(shù)數(shù)據(jù)中心都采用了該規(guī)范。它基于1.75英寸(44.5毫米)高度的機架單元(U)，設備高度具體分為1U、2U、4U等。雖然大多數(shù)設備都充分采用了這個寬度，但半寬度設備越來越受歡迎，因為它可以提供更高密度每U的選擇。

To further increase density beyond the standard lay-out, blade servers offer increased flexibility for manufacturers. Blade servers typically consist of a standard-width chassis that occupies between 3U and 10U of a traditional rack. However, the servers are individual “blades” of various dimensions, which plug into the chassis. Additionally, shared resources such as cooling fans and power supplies may be located on thec hassis, further broadening thelimits of what is possible with blade design (Figure1).

為進一步增加超出標準布局的密度，刀片式服務器為制造商提供了更大的靈活性。刀片服務器通常由標準寬度的機箱組成，它占傳統(tǒng)機架的3U到10U高度。只不過服務器是不同尺寸獨立插入到機箱中的“刀片”。此外，共用資源如冷卻風扇和電源可能也位于機箱上，這進一步擴大了刀片設計的極限(圖1)。

Networking

網(wǎng)絡連接

Networking is the wa yservers are connected to other servers, other resources, andto the world outside the data center. Network topologies, the ways that networking equipment is connected, is a rapidly evolving topic that varies greatly based on the size andfunction of a workload. Traditional networking can easily be a source of bottlenecking if not optimized for a workload, but the current trend toward software-defined networking

（SDN）meets the dynamic demands on the network through abstraction and separation of the control from the hardware.

網(wǎng)絡是服務器連接到其他服務器、資源和外界數(shù)據(jù)中心方式。網(wǎng)絡拓撲，即網(wǎng)絡設備的連接方式，是一個快速發(fā)展的主題，它隨著工作負載的大小和功能的變化而變化。如果不針對工作負載進行優(yōu)化，傳統(tǒng)的網(wǎng)絡很容易成為瓶頸，然而目前的趨勢是采用軟件定義網(wǎng)絡（SDN），通過控制功能與硬件的分離，以滿足網(wǎng)絡的動態(tài)需求。

FIGURE1 Typical compute server rack and packaging.

圖1.典型計算服務器機架和封裝

At the basic level, switches provide communication between devices by receiving data and forwarding it to its destination via the correct port, in contrast to a hub tha receives data and forwards it to all othe rports. Since it would be impractical for every server in a data center of any considerable size to be connected to a single switch, often multiple switches are connected to form a hierarchy with data flowing up and down the hierarchy as required. Such a hierarchy can be functionally characterized into core, distribution, and edge switches.6

在通常情況下，交換機接收數(shù)據(jù)并通過正確的端口將其轉(zhuǎn)發(fā)到目的地，從而在設備之間提供通信；而集線器接收數(shù)據(jù)并將其轉(zhuǎn)發(fā)到其他所有端口。由于將任意規(guī)模的數(shù)據(jù)中心中的每臺服務器連接到單個交換機都是不切實際的，因此常需要連接多個交換機，以形成一個層級結(jié)構，并根據(jù)需要在層級結(jié)構中上下傳送數(shù)據(jù)。這種層級結(jié)構可以按功能劃分為核心、匯聚和邊緣交換機。

Based on the size and design of the data center, network implementations may take many forms. At the simplest level, equipment could be connected to thesame (core) switch. As the number of servers increases, it may be optimal to have the servers connected to edges witches, which are in turn each connected to the cores witch. If theneeds of the network exceed even that configuration, edge switches may be locatedwithin the server racks that each communicate with row level distribution switches that each join multiple edge switches to the core switch (Figure2).

根據(jù)數(shù)據(jù)中心的規(guī)模和設計，可以采用多種形式實現(xiàn)網(wǎng)絡連接。在最簡單的級別上，設備可以連接到同一個(核心)交換機。隨著服務器數(shù)量的增加，最好將服務器先連接到邊緣交換機，而邊緣交換機又依次連接到核心交換機。如果網(wǎng)絡需求甚至超過了該配置，則位于服務器機架中的邊緣交換機會通過行級匯聚交換機通信，再將多個邊緣交換機連接到核心交換機.

Current switch design, like nearly everything in the data center, is largely driven by performance. At its core, data is received through a port and reaches the physical layer chips. These communicate with an application-specific integrated circuit (ASIC) chip, which is a highly specialized chip designed to route data as quickly and intelligently as possible. The data flow though the physical layer to the proper outgoing port. Switches may also include a CPU that handles additional data processing such as encryption, but processing data adds significant latency to the otherwise low-latency switching.

與數(shù)據(jù)中心中的幾乎所有設備一樣，當前交換機的設計在很大程度上是由性能決定的。其核心是，數(shù)據(jù)通過端口接收并到達物理層芯片。它們與特定用途集成電路(ASIC)芯片通信，ASIC芯片是一種高度專用的芯片，旨在盡可能快速和智能地實現(xiàn)路由和數(shù)據(jù)轉(zhuǎn)發(fā)。數(shù)據(jù)通過物理層流向正確的輸出端口。交換機還可以包括一個CPU來進行額外的數(shù)據(jù)處理，比如加密，但是數(shù)據(jù)處理會給低時延的交換機增加明顯的延遲。

FIGURE2 Possible switching hierarchy based on network size.

圖2.基于網(wǎng)絡規(guī)模的可能的交換體系

In addition to just forwarding data to the right destination, the ASIC chip may also enforce priority flow control (PFC) rules that prioritize some data and deprioritize other data to provide the desired result, such as prioritizing streaming video to be delivered without interruption.

除了將數(shù)據(jù)轉(zhuǎn)發(fā)到正確的目的地之外，ASIC芯片還可以執(zhí)行優(yōu)先級流控制(PFC)規(guī)則，對某些數(shù)據(jù)進行優(yōu)先級排序，以提供所需的結(jié)果，比如對連續(xù)傳輸?shù)囊曨l流進行優(yōu)先級排序。

Networking equipment may also be classify based on an abstraction of its function within the data center, using the open system interconnection (OS) seven-layer model. The majority of networking equipment resides at Layers 1 to 3, which are the physical layer, the data link layer, and the network layer, respectively. A description of each layer follows:

· Layer 1: Physica llayer equipment such as hubs and repeaters only deal with the raw bit stream.

· Layer 2: Data link layer equipment such as bridges and switches deal with routing entire frames from Point A to Point B.

· Layer 3: Network layer equipment such as a router deals with higher order functions such as addressing, path determination, and subnets.

· Layers 4 to 7: These serve even higher-order functions, ranging from betweennetworks to ultimately communication with the application layer and the human m- achine interface.

網(wǎng)絡設備也可以根據(jù)數(shù)據(jù)中心內(nèi)部功能，使用開放系統(tǒng)互連(OS)七層模型進行抽象分層。大多數(shù)網(wǎng)絡設備位于第1層到第3層，分別是物理層、數(shù)據(jù)鏈路層和網(wǎng)絡層。以下是對每一層的描述：

第1層: 物理層設備，如集線器和中繼器，只處理原始比特流。

第2層: 數(shù)據(jù)鏈路層設備，如網(wǎng)橋和對數(shù)據(jù)幀進行轉(zhuǎn)發(fā)的交換機。

第3層: 網(wǎng)絡層設備，如具有更高級功能（尋址、路由選擇和劃分子網(wǎng)）的路由器。

第4到7層: 提供更高級的功能，從網(wǎng)絡之間的通信到最終與應用層和人機界面的通信。

Storage Arrays

存儲陣列

A third major component of ITE within data centers is for the purpose of storing data, which is typically stored for one of four reasons. Data may be stored online, meaning it is current and able to be accessed rapidly. Data may be for backup to prevent the loss of information. Data may be for archival purposes, which should be accessible in the long term but is rarely needed. Or it may be for disaster recovery, which is similar to archival except that it is stored in a different physical location to guard against natural disasters.

數(shù)據(jù)中心內(nèi)的ITE的第三個主要組件用于存儲數(shù)據(jù)，通常數(shù)據(jù)存儲有以下四個目的之一：數(shù)據(jù)可以在線存儲，這意味著它是實時的，可以快速訪問；數(shù)據(jù)可以作為備份，以防止信息丟失；數(shù)據(jù)可用于存檔目的，可以長期訪問，盡管很少需要；或者也可以用于災難恢復，它類似于存檔，只是存儲在不同的物理位置以防止自然災害。

A typical consumer’s computer may include one o two hard drives that are individually managed by that machine. However, when servers need to store data, especially where that data needs to be accessible by tens to thousands of servers, it simply is not feasible for each server to manage individual hard drives. Storage arrays are the solution to this problem.

一個典型的消費級電腦可能包括一個或兩個硬盤驅(qū)動器，由該機器單獨管理。然而，當服務器需要存儲數(shù)據(jù)時，特別是那些數(shù)據(jù)需要由無數(shù)臺服務器訪問的地方，每個服務器管理單個硬盤驅(qū)動器是不可行的。存儲陣列正是這個問題的解決方案。

Storage arrays abstrac tindividual storage devices (HDDsorSSDs) and aggregate them into larger arrays that appear as a single logical unit. The presentation of devices may be asjust a bunch of disks (JBOD), but commonly the storage devices are grouped togethe into a redundantarray of independent disks (RAID) to improve performance or enhance redundancy.

存儲陣列將單個存儲設備(HDD或SSD)組合成更大的陣列，并表現(xiàn)為單個邏輯單元。設備的表現(xiàn)形式可以只是簡單磁盤捆綁(JBOD)，但通常是將存儲設備組合成為獨立磁盤冗余陣列(RAID)，以提高性能或增強冗余。

RAID works by “striping”data across multiple devices, which can reduce the data written by each disk, increasing how quickly the data can be written (RAID 0). The RAID array may also use additional devices to write data redundantly across multiple disks (RAID 1).

RAID通過跨多個設備“分段”數(shù)據(jù)，可以減少每個磁盤寫入的數(shù)據(jù)，提高數(shù)據(jù)的寫入速度(RAID 0)。RAID陣列還可以使用額外的設備跨多個磁盤實現(xiàn)冗余數(shù)據(jù)寫入(RAID 1)。

More complex RAID configurations can provide both performance and redundancy. For example, RAID 4 and 5 do this by striping data across multiple devices, and then calculating the parity of each bit in each corresponding stripe of data (essentially whether the sum of bits is even or odd) and writing the parity bit to a redundant device. If any stripe is lost, the parity of the remaining stripes can be used to determine the lost bit. RAID 4 uses a dedicated parity device, whereas RAID 5 distributes the parity bits across all of the devices.

更復雜的RAID配置可以提供性能和冗余。例如，RAID 4和RAID 5通過跨多個設備分段數(shù)據(jù)來實現(xiàn)這一點，然后計算每個對應數(shù)據(jù)段中的每位的奇偶校驗(本質(zhì)上無論位的和是偶數(shù)還是奇數(shù))，并將校驗位寫入冗余設備。如果任意數(shù)據(jù)段丟失，則可以使用其余段的校驗位來確定丟失的位。RAID 4使用專用奇偶校驗設備，而RAID 5將奇偶校驗位分布在所有設備上。

Beyond RAID itself, storage arrays typically have redundant power supplies, RAID controllers, and ports to provide resiliency and reduce points of failure. Each device in the storage array is accessible by both controllers, which may use either power supply, and which may use either set of ports to communicate.

除了RAID本身，存儲陣列通常還具有冗余電源、RAID控制器和端口，以提供彈性和減少故障點。存儲陣列中的每個設備都可由兩個控制器訪問，控制器可以使用任何一個電源，也可以使用任何一組端口進行通信。

As mentioned before, tape storage still plays a role in the data center, particularly for archive and backup, in spite of newer technologies. Tape formats have been updated throughout the years with higher capacities and faster speeds, now nearing 10 terabytes each. Although individual tape drives are available, tape drives in the data center are most often found within tape libraries that manage a large number of tapes at once.

如上所述，盡管有了更新的技術，磁帶存儲仍然在數(shù)據(jù)中心中發(fā)揮作用，特別是用于存檔和備份。多年來，磁帶格式一直在以更高的容量和更快的速度更新，現(xiàn)在每種格式的容量都接近10TB。雖然可以單獨使用磁帶驅(qū)動器，但是數(shù)據(jù)中心中的磁帶驅(qū)動器通常位于同時管理大量磁帶的磁帶庫中。

Summary

小結(jié)

Today’s ITE consists of several very distinct types of hardware (servers, networking, and storage), each with its own unique designs and functions for supporting different types of data and services. Each of these types of ITE will correspondingly interact with the data center infrastructure in different ways.

今天的ITE由幾種完全不同的硬件組成(服務器、網(wǎng)絡和存儲)，每種硬件都有自己獨特的設計和功能來支持不同類型的數(shù)據(jù)和服務。每種類型的ITE都將以不同的方式與數(shù)據(jù)中心基礎設施發(fā)生相應的交互。

It is reasonable to believe that the IT industry is currently undergoing more rapid change than almost anything it has experienced. Not only is data within existing segments being created, stored, and processed more quickly than ever before, but entirely new IT segments are emerging, such as virtual reality (VR) and self-driving vehicles. These changes are placing increased demands on data centers and the ITE in them.

有理由相信，IT行業(yè)目前正經(jīng)歷著比以往任何時候都更快的變革。不僅現(xiàn)有段中的數(shù)據(jù)產(chǎn)生、存儲和處理速度比以往任何時候都要快，而且全新的IT應用正在涌現(xiàn)，比如虛擬現(xiàn)實(VR)和無人駕駛汽車。這些變化對數(shù)據(jù)中心和其中的ITE提出了更高的需求。

By understanding the fundamental roles of ITE (servers, networking, and storage), its changes, and how it interacts with the data center HVAC, data center designers will be better equipped to handle this changing landscape.

通過了解ITE的基本類型(服務器、網(wǎng)絡和存儲)、變化、及其如何與數(shù)據(jù)中心暖通空調(diào)相互影響，數(shù)據(jù)中心設計師將能更好地應對這種變化的前景。