How does a microkernel enhance security?
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By running less code in kernel mode.
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How does a microkernel enhance security?
By running less code in kernel mode.
What are the two types of movement between levels of storage hierarchy?
Explicit and implicit.
What is the title of the book referenced?
Operating System Concepts – 10th Edition
What are the two methods for handling I/O?
What are the two types of designs mentioned for multi-chip and multicore systems?
Multi-chip and multicore designs.
What is the bottom layer in the layered approach?
Layer 0, which is the hardware.
Which operating system is an example of a more complex structure?
UNIX.
What is the focus of the chapter titled 'Storage - Device Hierarchy'?
It discusses the organization and structure of storage devices in computer systems.
Who are the authors of the book?
Silberschatz, Galvin, and Gagne.
What is the focus of the book?
Computer System Architecture
In a NUMA system, how does memory access differ from Uniform Memory Access systems?
In NUMA, some memory accesses are faster than others, while in UMA, all memory accesses are uniform in speed.
How does the system call interface work?
It maintains a table indexed by system call numbers and invokes the intended system call in the OS kernel.
How do you configure the Linux kernel?
Using the command 'make menuconfig'.
What is the primary focus of Chapter 2 in 'Operating System Concepts'?
Operating System Services.
What does NUMA stand for?
Non-Uniform Memory Access.
What allows for concurrent execution in a computer system?
The presence of multiple CPUs and device controllers.
How does the operating system determine the type of interrupt that has occurred?
It uses separate segments of code to identify the interrupt type.
What does a chassis containing multiple separate systems refer to?
A physical enclosure that houses multiple independent computing systems.
What are the two separable parts of the UNIX operating system?
Systems programs and the kernel.
What does a layered operating system structure provide?
An abstraction.
How does the device controller operate in Direct Memory Access?
It transfers blocks of data from buffer storage directly to main memory without CPU intervention.
What does a multiprogrammed system allow?
Multiple processes to reside in memory at the same time.
What edition of 'Operating System Concepts' is referenced?
10th Edition.
Who are the authors of 'Operating System Concepts'?
Silberschatz, Galvin, and Gagne.
What are loadable kernel modules (LKMs)?
Components that can be loaded into the kernel as needed.
What is the purpose of a system call sequence in file operations?
To perform actions such as copying the contents of one file to another file.
Who are the authors of the book?
Silberschatz, Galvin, and Gagne.
What is the primary focus of the memory layout in a multiprogrammed system?
To efficiently manage memory for multiple processes running simultaneously.
What edition of 'Operating System Concepts' is referenced?
10th Edition.
What is caching?
An important principle where information in use is copied from slower to faster storage temporarily.
What are the main functions of a microkernel?
To manage low-level address space, process, and communication, while other services run in user space.
How many interrupts are generated per block in Direct Memory Access?
Only one interrupt is generated per block, rather than one interrupt per byte.
What limitation did the original UNIX operating system have?
Limited by hardware functionality.
What is the main topic of the provided text?
Parameter Passing via Table.
What is a characteristic of a general-purpose operating system?
It is a very large program.
What is the early version of the Macintosh Finder?
The Macintosh Finder (1985).
What is typically associated with each system call?
A number.
What is the architecture commonly associated with modern computers?
Von Neumann architecture.
What does an interrupt do in an operating system?
Transfers control to the interrupt service routine through the interrupt vector.
How do programs typically access system calls?
Via a high-level Application Programming Interface (API) rather than direct system call use.
What does the kernel do after loading?
Starts system daemons, which are services provided outside of the kernel.
What are the three most common APIs mentioned for system calls?
Win32 API for Windows, POSIX API for POSIX-based systems, and Java API for the Java virtual machine (JVM).
Which operating systems implement loadable kernel modules?
Linux, Solaris, etc.
What is the role of the bootstrap loader?
It locates the kernel, loads it into memory, and starts it.
What type of storage media is used for backing up files?
Stable (non-volatile) storage media.
What does the operating system do to preserve the state of the CPU during an interrupt?
It stores the registers and the program counter.
In the first method of I/O handling, when does control return to the user program?
Only upon I/O completion.
What is the purpose of a timer in an operating system?
To prevent infinite loops or process hogging resources.
Why are applications often specific to an operating system?
Because apps compiled on one system are usually not executable on other operating systems.
What is the purpose of a Standard API in operating systems?
To provide a set of functions for application developers to interact with the operating system.
What is the structure of Windows operating system?
Mostly monolithic, with a microkernel for different subsystem personalities.
What does GUI stand for?
Graphical User Interface.
How can applications be made to run on multiple operating systems?
By using interpreted languages like Python or Ruby, or by using a VM like Java.
What does a loader do?
It loads the executable file into memory for execution.
What are kernel extensions in Mac OS X?
Dynamically loadable modules.
Where is the bootstrap loader typically stored?
In ROM or EEPROM.
Why are applications often specific to certain operating systems?
Because of differences in system calls and services.
What do users generally want from an operating system?
Convenience, ease of use, and good performance.
What is a potential disadvantage of microkernel systems?
They may have performance overhead due to increased communication between user space and kernel space.
What does CLI stand for?
Command Line Interface.
What environment do operating systems provide?
An environment for execution of programs and services to programs and users.
What does process management allow in terms of process states?
Suspending and resuming processes.
What is often required in addition to the identity of a desired system call?
More information, such as the exact type and amount of information, which varies according to the OS and call.
How does an Operating System contribute to user experience?
By making the computer system convenient to use.
What are the characteristics of mobile devices regarding operating systems?
They are resource-poor and optimized for usability and battery life.
What is a good approximation of what an operating system includes?
"Everything a vendor ships when you order an operating system."
What type of user interfaces do mobile devices typically use?
Touch screens and voice recognition.
What is the title of the book referenced?
Operating System Concepts – 10th Edition.
How is the traditional UNIX system structure described?
Beyond simple but not fully layered.
What is a characteristic of most modern operating systems?
They are hybrid systems that combine multiple approaches.
What is a system call?
A programming interface to the services provided by the operating system.
What does API stand for in the context of operating systems?
Application Programming Interface.
What are the main services provided by an operating system?
Operating System Services.
How are core components of LKMs structured?
Each core component is separate and communicates over known interfaces.
What does API stand for in the context of operating systems?
Application Programming Interface.
How do LKMs compare to traditional layers in operating systems?
They are similar to layers but offer more flexibility.
What edition of 'Operating System Concepts' is referenced?
10th Edition.
What must the interrupt architecture save?
The address of the interrupted instruction.
How does a microkernel differ from a monolithic kernel?
A microkernel has a smaller code base and runs most services in user space, while a monolithic kernel includes many services in kernel space.
What is the primary purpose of mass-storage management?
To store data that does not fit in main memory or must be kept for a long period.
What happens if the information is found in the cache?
The information is used directly from the cache, which is faster.
What is the primary characteristic of main memory?
It is the only large storage media that the CPU can access directly.
What occurs if the information is not found in the cache?
The data is copied to the cache and then used from there.
What activities are involved in operating system mass-storage management?
Mounting and unmounting, free-space management, storage allocation, disk scheduling, partitioning, and protection.
Which operating system is known for its GUI with a command shell?
Microsoft Windows.
What does the bootstrap program load after initialization?
The operating system kernel.
Is there a universally accepted definition of an operating system?
No, there is no universally accepted definition.
Where can a CLI be implemented?
In the kernel or by a systems program.
What tools can be used for monitoring operating system performance?
Tools include performance monitors, resource usage analyzers, and logging utilities.
What are the types of user interfaces mentioned?
Command-Line Interface (CLI), Graphics User Interface (GUI), touch-screen, and Batch.
What are some optional GUI interfaces available for Unix and Linux?
CDE, KDE, GNOME.
What is User Mode?
A restricted mode where applications run with limited privileges to protect system integrity.
What does protection in system calls refer to?
Controlling access to resources, getting and setting permissions, and managing user access.
What is the Bourne Shell?
A command interpreter for Unix operating systems.
What is the layered approach in operating systems?
The operating system is divided into a number of layers, each built on top of lower layers.
What is the title of the book referenced?
Operating System Concepts – 10th Edition.
What are the categories of system programs?
File manipulation, status information, programming language support, program loading and execution, communications, background services, application programs.
How do Linux and Solaris kernels operate?
They are monolithic but also modular for dynamic loading of functionality.
How do most users perceive the operating system?
Through system programs, not the actual system calls.
What does the kernel of UNIX consist of?
Everything below the system-call interface and above the physical hardware.
Who are the authors of 'Operating System Concepts'?
Silberschatz, Galvin, and Gagne.
What must the caller know about system calls?
The caller needs to obey the API and understand the expected outcome, but not the implementation details.
What are the four main components of a computer system?
Hardware, Operating System, Application Programs, Users.
What does POSIX stand for?
Portable Operating System Interface.
How does the operating system relate to system calls?
The operating system provides the interface through which system calls are made to access hardware and system resources.
What are the services provided by an operating system?
Services include managing hardware resources, providing user interfaces, and facilitating application execution.
What is the role of logging in an operating system?
To keep track of which users use how much and what kinds of computer resources.
What are some problems that can occur with processes?
Infinite loops, processes modifying each other, or issues with the operating system.
How can communication occur between processes in an operating system?
Via shared memory or through message passing (packets moved by the OS).
What are the different strategies for designing operating systems?
Monolithic, layered, microkernel, modular, and hybrid strategies.
What happens when an interrupt occurs during the I/O cycle?
The CPU stops its current task and executes the interrupt service routine.
What does device management in system calls involve?
Requesting and releasing devices, reading and writing data, and managing device attributes.
What is a potential drawback of SMP?
Increased complexity in managing shared resources.
What is the primary role of memory management?
To determine what is in memory and when.
What are shells in the context of CLI?
Different flavors of command line interpreters.
How can debugging facilities benefit users and programmers?
They can greatly enhance their abilities to efficiently use the system.
What must the system be able to do for program execution?
Load a program into memory and run it, ending execution normally or abnormally.
What is the design structure of Linux?
Monolithic plus modular design.
What is a system call?
A mechanism that allows user-level processes to request services from the operating system.
What edition of 'Operating System Concepts' is referenced?
10th Edition.
What is the highest layer in the layered approach?
Layer N, which is the user interface.
In the second method of I/O handling, when does control return to the user program?
Without waiting for I/O completion.
What is the primary role of a linker?
To combine multiple object files into a single executable file.
What is contained in the interrupt vector?
Addresses of all the service routines.
What happens when power is initialized on a system?
Execution starts at a fixed memory location.
Where is caching performed?
At many levels in a computer, including hardware, operating system, and software.
What is Symmetric Multiprocessing (SMP)?
A computer architecture where two or more identical processors are connected to a single shared main memory.
What devices are typically used with a GUI?
Mouse, keyboard, and monitor.
What is a key characteristic of Symmetric Multiprocessing?
All processors share the same memory and I/O resources.
What is the purpose of the bootstrap program?
It is loaded at power-up or reboot to initialize all aspects of the system.
How is an operating system described in relation to interrupts?
It is interrupt driven.
How does the interrupt-driven I/O cycle improve system efficiency?
By enabling multitasking and reducing CPU idle time during I/O operations.
What are some functions of file management system calls?
Creating, deleting, opening, closing, reading, writing, and repositioning files.
What is one of the goals of an Operating System?
To execute user programs and make solving user problems easier.
What can execute concurrently in a computer system?
I/O devices and the CPU.
What are important design problems related to caching?
Cache management, cache size, and replacement policy.
Why is user authentication important in an operating system?
To ensure security from outsiders and control access to information.
How is a job selected for execution in a multiprogramming system?
Through job scheduling.
How do processes communicate with each other in an operating system?
Through mechanisms for process communication.
What happens if there are more parameters than available registers?
Parameters can be stored in a block or table in memory, with the address of the block passed as a parameter in a register.
What is the purpose of an operating system device driver?
To manage a particular type of device controller.
What happens to the mode bit when kernel code is executing?
The mode bit is set to 'kernel'.
How is the mode bit reset to 'user' after a system call?
The return from the system call resets it to user mode.
Which organization started the free software movement?
Free Software Foundation (FSF).
What is the purpose of access control in file systems?
To determine who can access what.
What do CPUs and devices compete for in a computer system?
Memory cycles.
What is a dual-core design?
A system that contains multiple cores on a single chip.
What is an example of a simple structure operating system?
MS-DOS.
What are the benefits of hybrid operating systems?
They address performance, security, and usability needs.
What is Direct Memory Access (DMA) used for?
For high-speed I/O devices able to transmit information at close to memory speeds.
What is the title of the book referenced?
Operating System Concepts – 10th Edition.
What does the operating system do with the timer's counter?
It sets the counter using a privileged instruction.
Who are the authors of the book?
Silberschatz, Galvin, and Gagne.
What are the mechanisms through which applications interact with the operating system?
System Calls.
Why is memory layout important in operating systems?
It helps optimize resource utilization and process execution.
What is the purpose of resource allocation in an operating system?
To allocate resources to multiple users or jobs running concurrently.
What is a key characteristic of memory management in multiprogrammed systems?
Dynamic allocation and deallocation of memory.
What is a method for compiling applications to run on different operating systems?
Using a standard language like C and compiling separately on each operating system.
What is the role of the operating system in a computer system?
Controls and coordinates the use of hardware among various applications and users.
How are system calls used in operating systems?
System calls provide the interface between a running program and the operating system.
How is the disk surface of an HDD organized?
Logically divided into tracks, which are subdivided into sectors.
What is the purpose of dual-mode operation in an operating system?
To protect the OS and other system components.
What role does the disk controller play in HDDs?
It determines the logical interaction between the device and the computer.
What is swapping in operating systems?
Moving processes in and out of memory to run when they don't fit.
Can you name an example of a system call in Windows?
CreateFile, which is used to create or open a file.
What happens after the bootstrap program loads the operating system kernel?
It starts the execution of the operating system.
What does disk scheduling refer to in mass-storage management?
The process of determining the order in which disk I/O requests are processed.
What does the OS provide in terms of information storage?
A uniform, logical view of information storage.
What is the kernel in the context of an operating system?
The one program running at all times on the computer, part of the operating system.
What is one benefit of using a microkernel?
Easier to extend the microkernel.
What controls each medium in file system management?
A device, such as a disk drive or tape drive.
What is the primary focus of the text?
A view of operating system services.
What is a key characteristic of a Non-Uniform Memory Access system?
Memory access times vary depending on the memory location relative to the processor.
What is the main focus of the referenced section?
Overview of Computer System Structure.
What programming approach do many modern operating systems use for LKMs?
An object-oriented approach.
How does the timer function in an operating system?
It interrupts the computer after a set time period.
What principle does the layered approach utilize?
Modularity, where each layer uses functions and services of only lower-level layers.
What is the main focus of the referenced book?
Operating systems and their concepts.
What is an example of a microkernel operating system?
Mach.
What is multitasking in operating systems?
A logical extension of batch systems where the CPU switches jobs frequently, allowing user interaction with each job.
What is the focus area of the referenced content?
Storage Structure.
What hides most details of the OS interface from the programmer?
The API (Application Programming Interface).
How does the linker handle external references?
By resolving symbols and addresses between different object files.
What do icons in a GUI represent?
Files, programs, actions, etc.
What is the main purpose of multiprogramming in a batch system?
To keep the CPU always busy by organizing jobs.
What is one of the key activities of process management in an operating system?
Creating and deleting both user and system processes.
What are some examples of application programs?
Word processors, compilers, web browsers, database systems, video games.
What is involved in building and booting an operating system?
The process of creating the OS and initializing it on hardware.
Why is error detection important for an operating system?
The OS needs to be constantly aware of possible errors that may occur in hardware, I/O devices, or user programs.
Is main memory typically volatile or nonvolatile?
Typically volatile.
What are Non-volatile memory (NVM) devices known for?
Being faster than hard disks and nonvolatile.
What is included in information maintenance system calls?
Getting and setting time or date, and accessing system data.
What is Kernel Mode?
A mode where the operating system has full access to all hardware and can execute any CPU instruction.
What happens when a job has to wait for I/O in a multiprogramming system?
The operating system switches to another job.
What are the activities involved in memory management?
Keeping track of memory usage, deciding what to move in/out of memory, and allocating/deallocating memory space.
What are free and open-source operating systems?
Operating systems made available in source-code format rather than just binary closed-source and proprietary.
What is the significance of file-system manipulation in operating systems?
Programs need to read, write, create, delete, search, and manage files and directories.
What are privileged instructions?
Instructions that can only be executed in kernel mode.
What is the basic operation of a computer system?
One or more CPUs and device controllers connect through a common bus providing access to shared memory.
Who are the authors of the book?
Silberschatz, Galvin, and Gagne
What do system programs provide for program development and execution?
A convenient environment.
What is the structure of the original UNIX operating system?
Monolithic Structure.
In which programming languages are system calls typically written?
High-level languages like C or C++.
What is the purpose of the bootstrap program in an operating system?
To initialize the system and load the kernel.
What does the system call interface return?
The status of the system call and any return values.
What is the purpose of system calls?
They are the interface between the operating system and the user programs.
What functions does the UNIX kernel provide?
File system, CPU scheduling, memory management, and other operating-system functions.
What is a system call?
A mechanism that allows user-level applications to request services from the operating system.
What do linkers and loaders do in the context of operating systems?
They manage the process of combining and loading programs into memory.
What is the desired response time for interactive computing?
Less than 1 second.
What manages the system call interface?
The run-time support library, which includes a set of functions built into libraries with the compiler.
What is a process in the context of multitasking?
A program that is executing in memory.
In SMP, how do processors communicate?
Through shared memory.
What modern system replaces BIOS?
Unified Extensible Firmware Interface (UEFI).
What type of access does main memory provide?
Random access.
What is a common bootstrap loader that allows kernel selection?
GRUB.
Who are considered users in a computer system?
People, machines, and other computers.
What is the purpose of operating system debugging?
To identify and fix issues within the operating system.
What should the OS do when it detects an error?
Take appropriate action to ensure correct and consistent computing.
What boot states can boot loaders frequently allow?
Various boot states, such as single user mode.
How does memory management optimize system performance?
By optimizing CPU utilization and computer response to users.
What is an advantage of having commands as names of programs in CLI?
Adding new features doesn’t require shell modification.
What happens after I/O starts in a user program?
Control returns to the user program only upon I/O completion.
Why is a microkernel considered more reliable?
Because less code is running in kernel mode.
What decisions does memory management make regarding processes?
Which processes (or parts thereof) and data to move into and out of memory.
What makes microkernels easier to port to new architectures?
Their modular design.
What is the purpose of separate segments of code in interrupt handling?
To determine what action should be taken for each type of interrupt.
What is the relationship between users and the operating system?
User and Operating System - Interface.
What is a microkernel?
A minimalistic kernel that provides only the essential services needed for the operating system.
What happens when the timer's counter reaches zero?
An interrupt is generated.
What is a key feature of a GUI?
User-friendly desktop metaphor interface.
When is the timer set up in relation to process scheduling?
Before scheduling a process to regain control or terminate a program that exceeds its allotted time.
What is a hardware interrupt?
An interrupt triggered by one of the devices.
What types of resources are typically allocated by an operating system?
CPU cycles, main memory, file storage, and I/O devices.
What is the purpose of the interrupt-driven I/O cycle?
To allow the CPU to perform other tasks while waiting for I/O operations to complete.
How can main memory be viewed in relation to secondary storage?
As a cache for secondary storage.
What is an Operating System?
A program that acts as an intermediary between a user of a computer and the computer hardware.
What is the role of an operating system in shared computers like mainframes?
To keep all users happy by efficiently allocating resources and managing execution of user programs.
What is the advantage of Symmetric Multiprocessing?
Improved performance and reliability through parallel processing.
What is required to execute a program?
All (or part) of the instructions and data must be in memory.
What are the two modes in dual-mode operation?
User mode and kernel mode.
What mechanism does the operating system provide for coordinating processes?
Mechanisms for process synchronization.
What type of kernel does Apple Mac OS X use?
UNIX kernel.
Can you name an example of a system call in Unix?
fork, which is used to create a new process.
What is the role of free-space management in mass-storage management?
To keep track of available storage space on the disk.
What is abstracted to create a logical storage unit in file system management?
Physical properties are abstracted to a logical storage unit called a file.
What may a running program require that involves I/O?
I/O operations, which may involve a file or an I/O device.
What are application programs?
All programs not associated with the operating system.
What additional software do today's operating systems include for application developers?
Middleware, which provides additional services such as databases, multimedia, and graphics.
What is the GNU Public License (GPL)?
A 'copyleft' license associated with the Free Software Foundation.
What does 'economy of scale' refer to in multiprocessor systems?
The cost advantages gained by using multiple processors.
Is VirtualBox open source?
Yes, it is open source and free on many platforms.
What is an example of a system call sequence?
Copying the contents of one file to another file.
What do different operating systems provide that affects application compatibility?
Each operating system provides its own unique system calls and file formats.
What is the storage hierarchy?
A system organized based on speed, cost, and volatility.
What components make up Apple Mac OS X?
Aqua UI, Cocoa programming environment, Mach microkernel, and BSD Unix parts.
Who are the authors of 'Operating System Concepts'?
Silberschatz, Galvin, and Gagne.
What is the purpose of the printf() function in C?
To output formatted text to the standard output.
What does the hardware component of a computer system provide?
Basic computing resources such as CPU, memory, and I/O devices.
What system call is invoked by the printf() library call?
The write() system call.
What is the two-step boot process?
The boot block at a fixed location is loaded by ROM code, which then loads the bootstrap loader from disk.
What aspects are considered in the design and implementation of an operating system?
Efficiency, usability, and resource management.
Where is the bootstrap program typically stored?
In ROM or EPROM, generally known as firmware.
What is a system call?
A mechanism that allows user-level processes to request services from the operating system.
In the context of C programming, what is a library call?
A function provided by a library that can be used in a program.
What is the process for booting an operating system?
The process involves loading the kernel into memory and initializing system components.
What is a common feature of almost all operating systems?
A user interface (UI).
What is the role of a device controller?
In charge of a particular device type.
What is a key efficiency goal of an Operating System?
To use the computer hardware in an efficient manner.
What does each device controller have to manage data?
A local buffer.
What is the purpose of system calls in operating systems?
To provide an interface for user applications to interact with the hardware and system resources.
What does partitioning mean in the context of mass-storage management?
Dividing the disk into separate sections for better organization and management.
What does the wait instruction do during I/O operations?
It idles the CPU until the next interrupt.
What are some varying properties of storage media?
Access speed, capacity, data-transfer rate, and access method (sequential or random).
What resources does a process need to accomplish its task?
CPU, memory, I/O, files, and initialization data.
How do free software and open-source software differ?
They are two different ideas championed by different groups of people.
What is a Virtual Machine Manager (VMM)?
Software like VMware Player or VirtualBox used to run guest operating systems for exploration.
What types of interrupts does the kernel handle?
Hardware interrupts and software interrupts.
What are the key factors in organizing storage systems?
Speed, cost, and volatility.
What is the Application Binary Interface (ABI)?
The ABI is the architecture equivalent of API, defining how different components of binary code can interface for a given operating system on a specific architecture.
What is caching in the context of storage systems?
Copying information into a faster storage system.
What are Hard Disk Drives (HDD) made of?
Rigid metal or glass platters covered with magnetic recording material.
What is a type of system call related to managing processes?
Process control, which includes creating, terminating, and executing processes.
What does the write() system call do?
It writes data to a file descriptor.
What happens when several jobs are ready to run at the same time?
CPU scheduling is required.
How does the size of the cache compare to the storage being cached?
The cache is smaller than the storage being cached.
What is the difference between protection and security in an operating system?
Protection involves controlling access to resources, while security involves defending the system from unauthorized access attempts.
What is an example of a microkernel?
Mach.
What happens during the transition to Kernel Mode?
The CPU switches to a more privileged mode, allowing access to protected resources.
Which operating system's kernel is partly based on Mach?
Mac OS X kernel (Darwin).
What does the mode bit do in dual-mode operation?
It distinguishes between user code and kernel code execution.
What is the purpose of kernel modules in a Linux kernel?
Kernel modules allow for extending the functionality of the kernel without rebooting the system.
What does the operating system provide to handle situations where processes cannot proceed?
Mechanisms for deadlock handling.
What are system programs?
Programs that ship with the operating system but are not part of the kernel.
What is the significance of protection in mass-storage management?
To ensure data integrity and prevent unauthorized access.
What is the process of I/O in relation to device controllers?
I/O is from the device to the local buffer of the controller.
What are multiprocessor systems also known as?
Parallel systems or tightly-coupled systems.
What does the device-status table contain?
Entries for each I/O device indicating its type, address, and state.
What is asymmetric multiprocessing?
A type of multiprocessor system where each processor is assigned a specific task.
What is checked first when accessing information in caching?
Faster storage (cache) is checked first to determine if the information is there.
What is one advantage of using a microkernel architecture?
Increased system stability and security due to reduced kernel size and complexity.
What is one function of operating system services related to user communication?
Processes may exchange information on the same computer or between computers over a network.
What is the difference between a linker and a loader?
The linker prepares the executable file, while the loader loads it into memory.
What is the transition from User to Kernel Mode?
It is the process that allows a program to request services from the operating system.
Why can't a single user always keep the CPU and I/O devices busy?
Because a single user may not have enough tasks to utilize both effectively.
Why is the transition from User to Kernel Mode necessary?
To ensure that user applications do not have direct access to hardware and critical system resources.
How do users of dedicated systems like workstations utilize resources?
They have dedicated resources but frequently use shared resources from servers.
What is the name of the GUI interface used in Apple Mac OS X?
Aqua.
What is an interrupt service routine?
A special function that handles the interrupt and manages the I/O operation.
What is the simplest method for passing parameters to the OS?
Passing the parameters in registers.
What trends are observed with Non-volatile memory (NVM) devices?
They are becoming more popular as capacity and performance increase, and prices drop.
What are communication-related system calls?
Creating and deleting communication connections, sending and receiving messages.
What is a characteristic of embedded computers in devices and automobiles?
They run primarily without user intervention and often have little or no user interface.
What does memory management keep track of?
Which parts of memory are currently being used and by whom.
What type of processor do most computer systems use?
A single general-purpose processor.
What are special-purpose processors?
Processors designed for specific tasks, often used alongside general-purpose processors.
What happens during process termination?
Reclaiming any reusable resources is required.
How does the OS determine device status?
By indexing into the I/O device table.
What is symmetric multiprocessing?
A type of multiprocessor system where each processor performs all tasks.
What is a trap or exception?
A software-generated interrupt caused by an error or a user request.
What is a software interrupt?
An exception or trap, such as a software error or a request for an operating system service.
Why is proper management of mass storage important?
It is central to the entire speed of computer operation.
Where was the GUI invented?
At Xerox PARC.
What does protection in an operating system ensure?
That all access to system resources is controlled.
What is a microkernel?
A microkernel moves as much functionality as possible from the kernel into user space.
What is the primary function of a CLI?
To fetch a command from the user and execute it.
What does multiprogramming do with jobs in the system?
It keeps a subset of total jobs in memory for execution.
What does the kernel do after it is loaded?
The system is then running.
What does virtual memory allow in operating systems?
Execution of processes that are not completely in memory.
What form does main memory usually take?
Dynamic Random-access Memory (DRAM).
How do user modules communicate in a microkernel architecture?
Through message passing.
What is secondary storage?
An extension of main memory that provides large nonvolatile storage capacity.
How does a GUI differ from a CLI?
A GUI uses graphical elements for user interaction, while a CLI allows direct command entry.
What is commonly pre-installed on purchased computers?
An operating system.
What distinguishes a program from a process?
A program is a passive entity, while a process is an active entity.
How many I/O requests can be outstanding at a time?
At most one I/O request is outstanding at a time.
What is a single-threaded process?
A process with one program counter specifying the location of the next instruction to execute.
What command is used to compile kernel modules in Linux?
'make modules'.
What happens to the mode bit when a user is running code?
The mode bit is set to 'user'.
Which operating systems use the block method for passing parameters?
Linux and Solaris.
How does the CPU interact with local buffers?
By moving data from/to main memory to/from local buffers.
What are the steps to generate an operating system from scratch?
Write source code, configure, compile, install, and boot the operating system.
What is the first step in building and booting Linux?
Download the Linux source code from http://www.kernel.org.
What are some activities performed by the OS in file system management?
Creating and deleting files and directories, manipulating files and directories, mapping files onto secondary storage, and backing up files.
What does the OS modify in the device-status table?
It includes interrupt information for the device.
What is the primary purpose of operating systems?
To run on a class of systems with a variety of peripherals.
What is a process in the context of operating systems?
A process is a program in execution and a unit of work within the system.
What is a detriment of microkernels?
Performance overhead of user space to kernel space communication.
How are files usually organized in a file system?
Into directories.
What is one advantage of multiprocessor systems?
Increased throughput.
What is meant by 'graceful degradation' in multiprocessor systems?
The ability to maintain functionality even when some components fail.
How are parameters passed using the stack method?
Parameters are pushed onto the stack by the program and popped off the stack by the operating system.
What is a wait loop in the context of I/O?
Contention for memory access while waiting for I/O completion.
How does a device controller inform the CPU that it has finished its operation?
By causing an interrupt.
What command is used to compile the Linux kernel?
'make'.
What is concurrency in operating systems?
Concurrency is achieved by multiplexing the CPUs among the processes/threads.
What movement do free and open-source operating systems counter?
The copy protection and Digital Rights Management (DRM) movement.
What is a key advantage of the block and stack methods for passing parameters?
They do not limit the number or length of parameters being passed.
What is a system call in relation to I/O?
A request to the OS to allow the user to wait for I/O completion.
How does a multi-threaded process differ from a single-threaded process?
A multi-threaded process has one program counter per thread.
What command is used to install the new kernel on the system?
'make install'.
Can you name examples of free and open-source operating systems?
GNU/Linux and BSD UNIX (including the core of Mac OS X).
How are kernel modules installed into vmlinuz?
Using the command 'make modules_install'.
What does the 'make' command produce when compiling the kernel?
vmlinuz, the kernel image.
What types of processes typically run concurrently in a system?
Some user processes and some operating system processes.
