DILLA UNIVERSITY
COLLEGE OF ENGINEERING AND TECHNOLOGY
SCHOOL OF ELECTRICAL AND COMPUTER
ENGINEERING
DEPARTMENT OF COMPUTER ENGINEERING
COURSE OPERATING SYSTEM
INDIVIDUAL ASSIGNMENT
Name
ID
1, Ayele Asmamaw ………………………………………………..5275/19
SUBMITTED DATE 6/05/2023
SUBMITTED TO MR BeIay
DILLA ETHIOPIA
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Operating Systems Overview
1. What is the relationship between operating systems and computer hardware?
An operating system (OS) is a software program that manages computer hardware and
provides a platform for other software to run on. The OS acts as a bridge between the
computer hardware and the software that runs on it.
Computer hardware refers to the physical components of a computer system, such as
the central processing unit (CPU), memory, storage devices, input/output (I/O) devices,
and other components. The operating system interacts with these hardware
components to manage their operation and provide an interface for software
applications to use.
The operating system communicates with the hardware through device drivers, which
are software programs that provide a standardized interface between the OS and the
hardware. The device drivers allow the OS to interact with the hardware components in
a consistent and predictable manner, regardless of the specific hardware configuration.
3. What are the primary differences between Network Operating System and
Distributed Operating System?
A network operating system (NOS) and a distributed operating system (DOS) are both
types of operating systems that are designed for use in networked environments.
However, there are some key differences between the two:
 Scope: A NOS is designed to manage and control a network of computers
and devices, while a DOS is designed to manage a group of interconnected
computers that work together as a single system.
 Resource Management: A NOS typically manages network resources such as
printers, servers, and storage devices, while a DOS manages both local and
remote resources as a single unified system.
 Communication: A NOS primarily provides communication services between
different devices on a network, while a DOS provides communication
services between different processes running on different computers.
 Fault Tolerance: A DOS is designed to be fault-tolerant, meaning that it can
continue to operate even if some of its nodes fail, while a NOS typically relies
on redundancy and failover mechanisms to ensure availability.
 Security: A NOS focuses more on network security and access control, while
a DOS focuses more on distributed security and protecting resources from
unauthorized access.
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Operating Systems Process
1. What is the Difference between a Job and a Process?
In operating systems, a job and a process are related concepts, but they have some key
differences:
 Definition: A job is a unit of work that a user or a program requests to be
executed by the operating system. A job can consist of one or more processes. A
process, on the other hand, is an instance of a program that is being executed by
the operating system.
 Relationship: A job can consist of multiple processes that are related to each
other and work together to achieve a common goal. A process, on the other
hand, is an individual unit of execution that can exist independently or as part of
a job.
 Lifecycle: A job has a lifecycle that includes the submission, processing, and
completion stages. A process also has a lifecycle that includes the creation,
execution, and termination stages.
 Resources: When a job is submitted, it may require a set of system resources such
as memory, CPU time, and I/O devices. These resources are allocated to the job
as a whole. When a process is created, it is allocated its own set of resources,
which may include memory, CPU time, and I/O devices.
 Scheduling: The operating system schedules jobs for execution based on various
criteria such as priority, available resources, and user input. Processes, on the
other hand, are scheduled for execution by the operating system based on their
priority, the state of the system, and other factors.
3. What are the advantages of Multiprocessing or Parallel System? Operating Systems
Types
Multiprocessing or parallel systems are operating systems that are designed to execute
multiple tasks or processes simultaneously on multiple processors or cores. There are
several advantages to using multiprocessing or parallel systems:
 Increased throughput: Multiprocessing systems can increase the overall throughput
of the system by executing multiple tasks or processes simultaneously. This can
result in faster response times and more efficient use of system resources.
 Improved performance: Parallel systems can improve the performance of individual
tasks or processes by dividing them into smaller sub-tasks that can be executed
concurrently. This can reduce the time required to complete each task, resulting in
faster overall performance.
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 Better resource utilization: Multiprocessing systems can better utilize system
resources such as CPU, memory, and I/O devices by distributing workloads across
multiple processors or cores. This can result in more efficient use of system resources
and improved system performance.
 Increased scalability: Parallel systems can be easily scaled up to handle larger
workloads by adding additional processors or cores. This can provide a cost-effective
way to increase system capacity as the workload grows.
 Improved fault tolerance: Multiprocessing systems can provide improved fault
tolerance by allowing critical tasks or processes to be executed on multiple
processors or cores. If one processor or core fails, the task or process can continue
executing on another processor or core, reducing the impact of system failures.
1. What are the differences between Batch processing system and Real Time
Processing System?
Batch processing systems and real-time processing systems are two different types of
operating systems that are designed for different types of applications. Here are the
main differences between them:
 Nature of Processing: Batch processing systems are designed to process a large
volume of data in batches, where data is collected and processed at a later time.
Real-time processing systems, on the other hand, process data as it is received in
real-time and provide immediate feedback.
 Response Time: Batch processing systems have a longer response time, as data is
processed in batches and there can be a delay between data collection and
processing. Real-time processing systems have a very short response time, as data is
processed as it is received, providing immediate feedback.

Resource Utilization: Batch processing systems can utilize system resources
more efficiently as tasks can be scheduled and executed in an order that
optimizes resource utilization. Real-time processing systems require a high
level of resource availability to ensure that data is processed in real-time.
 Application: Batch processing systems are suitable for applications that do not
require real-time processing, such as batch processing jobs like generating reports,
processing large volumes of data, and billing systems. Real-time processing systems
are suitable for applications that require immediate processing and response, such
as online transaction processing systems, real-time control systems, and monitoring
systems.
 Priority: Batch processing systems can prioritize tasks based on their importance and
schedule them accordingly. Real-time processing systems prioritize data based on its
importance and process it immediately.
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3. What are the differences between multiprocessing and multiprogramming?
Multiprocessing and multiprogramming are both techniques used in operating systems
to maximize the utilization of system resources, but they are different in their approach
and goals. Here are the main differences between multiprocessing and
multiprogramming:
 Definition: Multiprocessing refers to the use of multiple processors or cores to
execute multiple tasks or processes simultaneously. Multiprogramming, on the other
hand, refers to the technique of executing multiple programs simultaneously on a
single processor or core by dividing the processor's time among them.
 Primary goal: The primary goal of multiprocessing is to increase the overall
throughput and performance of the system by executing multiple tasks or processes
simultaneously across multiple processors or cores. The primary goal of
multiprogramming is to maximize the utilization of the processor by keeping it busy
and executing multiple programs simultaneously.
 Resource allocation: In multiprocessing, tasks or processes are assigned to different
processors or cores based on the availability of resources, such as CPU time,
memory, and I/O devices. In multiprogramming, the processor's time is divided
among multiple programs in a time-sharing manner, with each program receiving a
slice of CPU time.
 Context switching: In multiprocessing, context switching between different processes
or tasks is done by switching between different processors or cores, which can be
done quickly and efficiently. In multiprogramming, context switching between
different programs is done by saving the current program's context and restoring the
next program's context, which can be time-consuming and may impact performance.
 Concurrent execution: In multiprocessing, multiple tasks or processes can execute
truly concurrently on separate processors or cores, while in multiprogramming,
programs are executed interleaved in time on a single processor or core, giving the
appearance of concurrency.
Operating Systems Process Scheduling
1. What is a process scheduler? State the characteristics of a good process
scheduler? OR What is scheduling? What criteria affects the scheduler’s
performance?
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A process scheduler is a component of an operating system that determines the order in
which processes are executed on a CPU. The process scheduler determines which
process should be executed next and allocates CPU time accordingly. The main goal of
the process scheduler is to maximize the utilization of the CPU and ensure that all
processes receive fair and efficient use of system resources.
Here are the characteristics of a good process scheduler:
 Fairness: A good process scheduler should allocate CPU time fairly among all
processes, ensuring that no process is starved of CPU time.
 Efficiency: The scheduler should be efficient in allocating CPU time to processes,
minimizing the time that processes spend waiting for CPU time.
 Responsiveness: The scheduler should be able to respond quickly to changes
in system load and adjust the scheduling policy accordingly.
 Predictability: The scheduler should be predictable in its behavior, ensuring that the
order in which processes are scheduled remains consistent over time.
 Prioritization: The scheduler should be able to prioritize processes based on their
importance or priority level, ensuring that critical processes receive sufficient CPU
time.
The scheduling policy used by the scheduler can have a significant impact on its
performance.
The following criteria can affect the scheduler's performance:
 CPU utilization: The scheduler's performance is measured by the CPU utilization rate,
which is the percentage of time that the CPU is busy executing processes. The
scheduler should aim to maximize CPU utilization while avoiding resource
starvation and ensuring fairness.
 Response time: The response time is the time taken by the system to respond to
a user request. The scheduler should aim to minimize response time by allocating
CPU time efficiently and fairly.
 Throughput: The throughput is the number of processes completed per unit of time.
The scheduler should aim to maximize the system throughput by scheduling
processes efficiently and fairly.
 Fairness: The scheduler should aim to allocate CPU time fairly among all processes,
ensuring that no process is starved of CPU time.
 Priority: The scheduler should be able to prioritize processes based on their priority
level or importance, ensuring that critical processes receive sufficient CPU time.
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3. What is Shortest Remaining Time, SRT scheduling?
Shortest Remaining Time (SRT) scheduling is a CPU scheduling algorithm used in
operating systems to schedule processes based on the amount of time remaining for
the process to complete its execution. SRT is a preemptive algorithm, which means that
the currently executing process can be preempted by a higher-priority process that
arrives in the ready queue.
In SRT scheduling, the process with the shortest remaining burst time is given the
highest priority and is scheduled to run next. This means that if a new process arrives
with a shorter burst time than the currently executing process, the new process will
preempt the current process and start executing immediately.
5. What are the different principles which must be considered while selection of a
scheduling algorithm?
There are several principles that must be considered while selecting a scheduling
algorithm for an operating system. These principles include:
 Process priorities: The scheduling algorithm should be able to prioritize processes
based on their importance or priority level to ensure that critical processes receive
sufficient CPU time.
 CPU utilization: The scheduling algorithm should aim to maximize CPU utilization
while avoiding resource starvation and ensuring fairness.
 Response time: The scheduling algorithm should aim to minimize the response
time by allocating CPU time efficiently and fairly.
 Throughput: The scheduling algorithm should aim to maximize the system
throughput by scheduling processes efficiently and fairly.
 Fairness: The scheduling algorithm should aim to allocate CPU time fairly among all
processes, ensuring that no process is starved of CPU time.
 Preemption: The scheduling algorithm should support preemption to allow higherpriority processes to interrupt lower-priority processes and execute immediately.
 Predictability: The scheduling algorithm should be predictable in its behavior,
ensuring that the order in which processes are scheduled remains consistent over
time.
 Overhead: The scheduling algorithm should have minimal overhead in terms
of processing time and memory usage.
 Compatibility: The scheduling algorithm should be compatible with the system
architecture and hardware, ensuring that it can effectively utilize available resources.
 Scalability: The scheduling algorithm should be scalable to handle larger workloads
and increasing numbers of processes or threads.
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