【OS】操作系统高频面试题英文版(1)

  今天开始更新操作系统高频面试题英文版。同样也分为 Basic、Intermediate、Advanced 三部分。下面是 Basic 部分。音频文件下方获取。
【OS】操作系统高频面试题英文版(1)
【OS】操作系统高频面试题英文版(2)
【OS】操作系统高频面试题英文版(3)

What do you mean by an operating system? What are its basic functions?

Operating System (OS) is basically a software program that manages and handles all resources of a computer such as hardware and software. The first OS was introduced in the early 1950s known as GMOs. An OS is responsible for managing, handling, and coordinating overall activities and sharing of computer resources. It acts as an intermediary among users of computer and computer hardware.

你认为操作系统是什么意思？它的基本功能是什么？

操作系统（OS）基本上是一个软件程序，它管理和处理计算机的所有资源，例如硬件和软件。第一个操作系统是在 1950 年代初期引入的，称为 GMO。操作系统负责管理、处理和协调整体活动以及计算机资源的共享。它充当计算机和计算机硬件用户之间的中介。

Functions of OS:
There are many functions of the OS. Some of the important functions of OS are given below:

• Memory and Processor Management.
• Providing user interface to users.
• File Management and Device Management.
• Scheduling of resources and jobs.
• Error Detection.
• Security.

操作系统的功能：操作系统

操作系统的功能很多。操作系统的一些重要功能如下：

• 内存和处理器管理。
• 为用户提供用户界面。
• 文件管理和设备管理。
• 资源和作业的调度。
• 错误检测。
• 安全。

Basic OS Interview Questions

1. Why is the operating system important?

OS is the most essential and vital part of a computer without which it is considered useless. It enables an interface or acts like a link for interaction between computer software that is installed on OS and users. It also helps to communicate with hardware and also maintains balance among hardware and CPU. It also provides services to users and a platform for programs to run on. It performs all common tasks applications require.

1. 为什么操作系统很重要？

操作系统是计算机中最基本和最重要的部分，没有它计算机就被认为是不实用的。它为安装在操作系统上的计算机软件和用户之间的交互提供接口或充当链接。它还有助于与硬件进行通信，并保持硬件和 CPU 之间的平衡。它还为用户提供服务，为程序运行提供平台。它执行应用程序所需的所有常见任务。

2. What’s the main purpose of an OS? What are the different types of OS?

The main purpose of an OS is to execute user programs and make it easier for users to understand and interact with computers as well as run applications. It is specially designed to ensure that the computer system performs better by managing all computational activities. It also manages computer memory, processes, and operation of all hardware and software.

2. 操作系统的主要用途是什么？有哪些不同类型的操作系统？

操作系统的主要目的是执行用户程序，使用户更容易理解、与计算机交互以及运行应用程序。它经过专门设计，通过管理所有计算活动来确保计算机系统性能更好。它还管理计算机内存、进程以及所有硬件和软件的操作。

Types of OS:

• Batched OS (Example: Payroll System, Transactions Process, etc.)
• Multi-Programmed OS (Example: Windows OS, UNIX OS, etc.)
• Timesharing OS (Example: Multics, etc.)
• Distributed OS (LOCUS, etc.)
• Real-Time OS (PSOS, VRTX, etc.)

操作系统类型：

• 批处理操作系统（例如：工资系统、交易流程等）
• 多程序操作系统（例如：Windows OS、UNIX OS 等）
• 分时操作系统（例如：Multics 等）
• 分布式操作系统（LOCUS 等）
• 实时操作系统（PSOS、VRTX 等）

3. What are the benefits of a multiprocessor system?

A Multiprocessor system is a type of system that includes two or more CPUs. It involves the processing of different computer programs at the same time mostly by a computer system with two or more CPUs that are sharing single memory.

3. 多处理器系统有什么好处？

多处理器系统是一种包括两个或更多 CPU 的系统。它涉及同时处理不同的计算机程序，主要由具有两个或多个共享单个内存的 CPU 的计算机系统进行。

Benefits:

• Such systems are used widely nowadays to improve performance in systems that are running multiple programs concurrently.
• By increasing the number of processors, a greater number of tasks can be completed in unit time.
• One also gets a considerable increase in throughput and is cost-effective also as all processors share the same resources.
• It simply improves the reliability of the computer system.

好处：

• 如今，此类系统被广泛用于提高同时运行多个程序的系统的性能。
• 通过增加处理器的数量，可以在单位时间内完成更多的任务。
• 由于所有处理器共享相同的资源，因此还可以显着提高吞吐量并且具有成本效益。
• 它只是提高了计算机系统的可靠性。

4. What is RAID structure in OS? What are the different levels of RAID configuration?

RAID (Redundant Arrays of Independent Disks) is a method used to store data on Multiple hard disks therefore it is considered as data storage virtualization technology that combines multiple hard disks. It simply balances data protection, system performance, storage space, etc. It is used to improve the overall performance and reliability of data storage. It also increases the storage capacity of the system and its main purpose is to achieve data redundancy to reduce data loss.

4. OS 中的 RAID 结构是什么？RAID 配置有哪些不同级别？

RAID（独立冗余磁盘阵列）是一种用于将数据存储在多个硬盘上的方法，因此被认为是组合多个硬盘的数据存储虚拟化技术。它简单地平衡数据保护、系统性能、存储空间等，用于提高数据存储的整体性能和可靠性。它还增加了系统的存储容量，其主要目的是实现数据冗余以减少数据丢失。

Different levels of RAID

Nowadays, RAID is available in various schemes or RAID level as given below:

• RAID 0 - Non-redundant striping: This level is used to increase the performance of the server.
• RAID 1 - Mirroring and duplexing: This level is also known as disk mirroring and is considered the simplest way to implement fault tolerance.
• RAID 2 - Memory-style error-correcting codes: This level generally uses dedicated hamming code parity I.e., a liner form of error correction code.
• RAID 3 - Bit-interleaved Parity: This level requires a dedicated parity drive to store parity information.
• RAID 4 - Block-interleaved Parity: This level is similar to RAID 5 but the only difference is that this level confines all parity data to a single drive.
• RAID 5 - Block-interleaved distributed Parity: This level provides far better performance than disk mirroring and fault tolerance.
• RAID 6 - P+Q Redundancy: This level generally provides fault tolerance for two drive failures.

不同级别的 RAID

如今，RAID 可用于各种方案或 RAID 级别，如下所示：

• RAID 0 - 非冗余条带化：此级别用于提高服务器的性能。
• RAID 1 - 镜像和双工：此级别也称为磁盘镜像，被认为是实现容错的最简单方法。
• RAID 2 - 内存式纠错码：此级别通常使用专用汉明码奇偶校验，即纠错码的线性形式。
• RAID 3 - 位交错奇偶校验：此级别需要专用奇偶校验驱动器来存储奇偶校验信息。
• RAID 4 - 块交错奇偶校验：此级别类似于 RAID 5，但唯一的区别是此级别将所有奇偶校验数据限制在单个驱动器中。
• RAID 5 - 块交错分布式奇偶校验：此级别提供比磁盘镜像和容错更好的性能。
• RAID 6 - P+Q 冗余：此级别通常为两个驱动器故障提供容错。

5. What is GUI?

GUI (Graphical User Interface) is basically a type of user interface that allows users to use graphics to interact with OS. GUI is created because it is more user-friendly, less complex, and easier to understand rather than a command-line interface. Its main goal is to increase efficiency and ease of use. Instead of having to memorize commands, users can just click on a button to simply execute the procedure. Examples of GUI include Microsoft Windows, macOS, Apple’s iOS, etc.

5.什么是图形用户界面？

GUI（图形用户界面）基本上是一种用户界面，允许用户使用图形与操作系统进行交互。创建 GUI 是因为它比命令行界面更易于使用、不太复杂且更易于理解。其主要目标是提高效率和易用性。用户无需记住命令，只需单击一个按钮即可执行该过程。GUI 的示例包括 Microsoft Windows、macOS、Apple 的 iOS 等。

6. What is a Pipe and when it is used?

The pipe is generally a connection among two or more processes that are interrelated to each other. It is a mechanism that is used for inter-process communication using message passing. One can easily send information such as the output of one program process to another program process using a pipe. It can be used when two processes want to communicate one-way i.e., inter-process communication (IPC).

6. 什么是管道，何时使用？

管道通常是两个或多个相互关联的进程之间的连接。它是一种使用消息传递进行进程间通信的机制。人们可以使用管道轻松地将诸如一个程序进程的输出之类的信息发送到另一个程序进程。它可以在两个进程想要进行单向通信时使用，即进程间通信（IPC）。

7. What are the different kinds of operations that are possible on semaphore?

There are basically two atomic operations that are possible:

• Wait()
• Signal()

7. 信号量可以进行哪些不同类型的操作？

基本上有两种可能的原子操作：

• Wait()
• Signal()

8. What is a bootstrap program in OS?

It is generally a program that initializes OS during startup i.e., first code that is executed whenever computer system startups. OS is loaded through a bootstrapping process or program commonly known as booting. Overall OS only depends on the bootstrap program to perform and work correctly. It is fully stored in boot blocks at a fixed location on the disk. It also locates the kernel and loads it into the main memory after which the program starts its execution.

8. 什么是 OS 中的引导程序？

它通常是在启动期间初始化 OS 的程序，即在计算机系统启动时执行的第一个代码。操作系统是通过通常称为 booting 的引导过程或程序加载的。整个操作系统仅依赖于引导程序才能正常执行和工作。它完全存储在磁盘上固定位置的引导块中。它还定位内核并将其加载到主内存中，然后程序开始执行。

9. Explain demand paging?

Demand paging is a method that loads pages into memory on demand. This method is mostly used in virtual memory. In this, a page is only brought into memory when a location on that particular page is referenced during execution. The following steps are generally followed:

• Attempt to access the page.
• If the page is valid (in memory) then continue processing instructions as normal.
• If a page is invalid then a page-fault trap occurs.
• Check if the memory reference is a valid reference to a location on secondary memory. If not, the process is terminated (illegal memory access). Otherwise, we have to page in the required page.
• Schedule disk operation to read the desired page into main memory.
• Restart the instruction that was interrupted by the operating system trap.

9. 解释请求式页面调度？

请求式页面调度是一种按需将页面加载到内存中的方法。这种方法多用于虚拟内存。在这种情况下，只有在执行期间引用该特定页面上的位置时，才会将页面带入内存。一般遵循以下步骤：

• 尝试访问该页面。
• 如果页面有效（在内存中），则继续正常处理指令。
• 如果页面无效，则会发生页面错误陷阱。
• 检查内存引用是否是对辅助存储器上某个位置的有效引用。如果不是，则终止进程（非法内存访问）。否则，我们必须在需要的页面中进行分页。
• 调度磁盘操作以将所需的页面读入主内存。
• 重新启动被操作系统陷阱中断的指令。

10. What do you mean by RTOS?

Real Time Operating System (RTOS) is an operating system that is used for real-time applications i.e., for those applications where data processing should be done in a fixed and small measure of time. It performs much better on tasks that are needed to be executed within a short time. It also takes care of execution, monitoring, and all-controlling processes. It also occupies less memory and consumes fewer resources.

Types of RTOS:

• Hard Real-Time.
• Soft Real-Time.

RTOS is used in Air traffic control systems, Anti-lock Brake Systems, and Heart pacemakers.

10. RTOS 是什么意思？

实时操作系统 (RTOS) 是一种用于实时应用程序的操作系统，即，用于那些应在固定且小时间度量内完成数据处理的应用程序。它在需要在短时间内执行的任务上表现得更好。它还负责执行、监视和所有控制过程。它还占用更少的内存，消耗更少的资源。

实时操作系统的类型：

• 硬实时
• 软实时

RTOS 用于空中交通管制系统、防抱死制动系统和心脏起搏器。

11. What do you mean by process synchronization?

Process synchronization is basically a way to coordinate processes that use shared resources or data. It is very much essential to ensure synchronized execution of cooperating processes so that will maintain data consistency. Its main purpose is to share resources without any interference using mutual exclusion. There are two types of process synchronization:

• Independent Process.
• Cooperative Process.

11. 进程同步是什么意思？

进程同步基本上是一种协调进程的方法，这些进程使用共享资源或数据。确保协作流程的同步执行非常重要，这样才能保持数据的一致性。它的主要目的是使用互斥来共享资源而不受任何干扰。有两种类型的进程同步：

• 独立进程
• 合作过程

12. What is IPC? What are the different IPC mechanisms?

IPC (Interprocess Communication) is a mechanism that requires the use of resources like a memory that is shared between processes or threads. With IPC, OS allows different processes to communicate with each other. It is simply used for exchanging data between multiple threads in one or more programs or processes. In this mechanism, different processes can communicate with each other with the approval of the OS.

Different IPC Mechanisms:

• Pipes;
• Message Queue;
• Semaphores;
• Socket;
• Shared Memory;
• Signals.

12.什么是IPC？有哪些不同的 IPC 机制？

IPC（进程间通信）是一种需要使用共享资源（如在进程或线程之间共享的内存）的机制。通过 IPC，操作系统允许不同的进程相互通信。它仅用于在一个或多个程序或进程中的多个线程之间交换数据。在这种机制中，不同的进程可以在操作系统的批准下相互通信。

不同的 IPC 机制：

• 管道
• 消息队列
• 信号量
• 插座
• 共享内存
• 信号

13. What is different between main memory and secondary memory.

Main memory: Main memory in a computer is RAM (Random Access Memory). It is also known as primary memory or read-write memory or internal memory. The programs and data that the CPU requires during the execution of a program are stored in this memory.
Secondary memory: Secondary memory in a computer are storage devices that can store data and programs. It is also known as external memory or additional memory or backup memory or auxiliary memory. Such storage devices are capable of storing high-volume data. Storage devices can be hard drives, USB flash drives, CDs, etc.

Primary Memory	Secondary Memory
Data can be directly accessed by the processing unit.	Firstly, data is transferred to primary memory and after then routed to the processing unit.
It can be both volatile and non-volatile in nature.	It is non-volatile in nature.
It is more costly than secondary memory.	It is more cost-effective or less costly than primary memory.
It is temporary because data is stored temporarily.	It is permanent because data is stored permanently.
In this memory, data can be lost whenever there is a power failure.	In this memory, data is stored permanently and therefore cannot be lost even in case of power failure.
It is much faster than secondary memory and saves data that is currently used by the computer.	It is slower as compared to primary memory and saves different kinds of data in different formats.
It can be accessed by data.	It can be accessed by I/O channels.

13. 主存和辅助存储器有什么不同。

**主存储器：**计算机中的主存储器是 RAM（随机存取存储器）。它也被称为主存储器或读写存储器或内部存储器。CPU 在执行程序期间需要的程序和数据都存储在该存储器中。
**辅助存储器：**计算机中的辅助存储器是可以存储数据和程序的存储设备。它也被称为外部存储器或附加存储器或备份存储器或辅助存储器。这种存储设备能够存储大量数据。存储设备可以是硬盘驱动器、USB 闪存驱动器、CD 等。

主内存	辅助记忆
处理单元可以直接访问数据。	首先，数据被传输到主存储器，然后被路由到处理单元。
它本质上可以是易失性的和非易失性的。	它本质上是非易失性的。
它比辅助存储器更昂贵。	它比主存储器更具成本效益或成本更低。
它是临时的，因为数据是临时存储的。	它是永久的，因为数据是永久存储的。
在此内存中，每当发生电源故障时，数据都可能丢失。	在此存储器中，数据被永久存储，因此即使在断电的情况下也不会丢失。
它比辅助存储器快得多，并且可以保存计算机当前使用的数据。	与主存储器相比，它速度较慢，并且以不同的格式保存不同类型的数据。
它可以通过数据访问。	它可以通过 I/O 通道访问。

14. What do you mean by overlays in OS?

Overlays is basically a programming method that divides processes into pieces so that instructions that are important and need can be saved in memory. It does not need any type of support from the OS. It can run programs that are bigger in size than physical memory by only keeping only important data and instructions that can be needed at any given time.

14. 操作系统中的覆盖是什么意思？

覆盖基本上是一种编程方法，它将进程划分为多个部分，以便可以将重要且需要的指令保存在内存中。它不需要操作系统提供任何类型的支持。它可以运行比物理内存更大的程序，只保留在任何给定时间可能需要的重要数据和指令。

15. Write top 10 examples of OS?

Some of the top OS’s that are used mostly are given below:

• MS-Windows
• Ubuntu
• Mac OS
• Fedora
• Solaris
• Free BSD
• Chrome OS
• CentOS
• Debian
• Android