ISC 272 Final Exam Questions with
Latest Update
Interrupt Processing - ANSWER-a process that happens when priorities change on a
CPU. For example, when a thread attempts to read from a removable disk, but the
disk cannot be found.
preemptive scheduling - ANSWER-A scheduling method that enables a higher-
priority thread to interrupt and suspend a lower-priority thread.
priority-based scheduling - ANSWER-A scheduling method that determines which
ready thread should be dispatched to the CPU based on user or thread priority.
real-time scheduling - ANSWER-A scheduling method that guarantees a thread a
minimum amount of CPU time and enough resources to complete its function in a
specified time if the thread makes an explicit request when its created.
1) allow as many active processes as possible
2) respond quickly to changing memory demands of processes
3) prevent unauthorized changes to a process's memory regions
4) perform memory allocation and addressing as efficiently as possible - ANSWER-
Memory Allocation Goals
Single process systems involves only 2 running programs : the OS and an
application. Multitasking involves allows multiple programs and processes to run
simultaneously. - ANSWER-Compare resource allocation between single process
systems and multitasking systems.
Absolute Memory Address and Relative Memory Address - ANSWER-Memory
addressing types?
Memory fragmentation is the scattering of storage locations allocated to a single
process or purpose throughout noncontiguous locations in physical memory or
secondary storage devices. It is dealt with by performing a defragmentation of the
hard drive. - ANSWER-What is memory fragmentation and how is it addressed?
contiguous memory allocation - ANSWER-allocating of memory in a order on the
storage device in sequential order
Disadvantage: because things are stored in random places or things are deleted
between locations, small areas of the memory are empty and depending on the size,
could be too small for use of certain processes and over time, you lose space on
your computer. Furthermore, processes may have to split up which costs computing
time.
, Advantage: it allows portions of a process to be allocated to free partitions anywhere
in memory. - ANSWER-What are the advantages and disadvantages of
noncontiguous memory allocation?
Virtual Memory Management - ANSWER-A management method in which the OS
divides memory and programs into partitions called pages, which are held in
secondary storage until needed.
Page - ANSWER-A partition of a program normally between 1 and 4 KB, swapped
between primary and secondary storage.
Page Hit - ANSWER-Reference to a page held in memory.
Page Fault - ANSWER-A reference to a page held in secondary storage.
Swap Space - ANSWER-A secondary storage region reserved for the task of holding
pages not held in memory
Pipe - ANSWER-A region of shared memory though which multiple processes
executing on the same computer can exchange data
Socket - ANSWER-The combination of an IP Address with a port number used to
establish connection.
Remote Procedure Call - ANSWER-A protocol that enables a process on one
computer to call a process on another computer.
File Management System - ANSWER-The collection of system software that
performs file and secondary storage management and access functions.
1) Application program or command layer
2) File control (part of OS layer)
3) Storage I/O control (part of OS kernel)
4) Secondary storage devices - ANSWER-Functions of a FMS
Command Layer - ANSWER-The operating system layer that serves as the user
interface that allows users to run applications and OS utilities and manage system
resources.
Storage I/O Control Layer - ANSWER-An FMS layer that is part of the kernel that
accesses storage locations and manages data movement between storage devices
and memory.
File Control Layer - ANSWER-The FMS Layer that provides service functions for
manipulating files and directories, processes service calls from the command layer,
issues commands to the storage I/O control layer to interact with hardware, and
maintains the directory and storage allocation data structures. ( the bridge between
logical and physical views.)
The physical view is how the data is actually stored (i.e. on an SSD or harddisk).
Latest Update
Interrupt Processing - ANSWER-a process that happens when priorities change on a
CPU. For example, when a thread attempts to read from a removable disk, but the
disk cannot be found.
preemptive scheduling - ANSWER-A scheduling method that enables a higher-
priority thread to interrupt and suspend a lower-priority thread.
priority-based scheduling - ANSWER-A scheduling method that determines which
ready thread should be dispatched to the CPU based on user or thread priority.
real-time scheduling - ANSWER-A scheduling method that guarantees a thread a
minimum amount of CPU time and enough resources to complete its function in a
specified time if the thread makes an explicit request when its created.
1) allow as many active processes as possible
2) respond quickly to changing memory demands of processes
3) prevent unauthorized changes to a process's memory regions
4) perform memory allocation and addressing as efficiently as possible - ANSWER-
Memory Allocation Goals
Single process systems involves only 2 running programs : the OS and an
application. Multitasking involves allows multiple programs and processes to run
simultaneously. - ANSWER-Compare resource allocation between single process
systems and multitasking systems.
Absolute Memory Address and Relative Memory Address - ANSWER-Memory
addressing types?
Memory fragmentation is the scattering of storage locations allocated to a single
process or purpose throughout noncontiguous locations in physical memory or
secondary storage devices. It is dealt with by performing a defragmentation of the
hard drive. - ANSWER-What is memory fragmentation and how is it addressed?
contiguous memory allocation - ANSWER-allocating of memory in a order on the
storage device in sequential order
Disadvantage: because things are stored in random places or things are deleted
between locations, small areas of the memory are empty and depending on the size,
could be too small for use of certain processes and over time, you lose space on
your computer. Furthermore, processes may have to split up which costs computing
time.
, Advantage: it allows portions of a process to be allocated to free partitions anywhere
in memory. - ANSWER-What are the advantages and disadvantages of
noncontiguous memory allocation?
Virtual Memory Management - ANSWER-A management method in which the OS
divides memory and programs into partitions called pages, which are held in
secondary storage until needed.
Page - ANSWER-A partition of a program normally between 1 and 4 KB, swapped
between primary and secondary storage.
Page Hit - ANSWER-Reference to a page held in memory.
Page Fault - ANSWER-A reference to a page held in secondary storage.
Swap Space - ANSWER-A secondary storage region reserved for the task of holding
pages not held in memory
Pipe - ANSWER-A region of shared memory though which multiple processes
executing on the same computer can exchange data
Socket - ANSWER-The combination of an IP Address with a port number used to
establish connection.
Remote Procedure Call - ANSWER-A protocol that enables a process on one
computer to call a process on another computer.
File Management System - ANSWER-The collection of system software that
performs file and secondary storage management and access functions.
1) Application program or command layer
2) File control (part of OS layer)
3) Storage I/O control (part of OS kernel)
4) Secondary storage devices - ANSWER-Functions of a FMS
Command Layer - ANSWER-The operating system layer that serves as the user
interface that allows users to run applications and OS utilities and manage system
resources.
Storage I/O Control Layer - ANSWER-An FMS layer that is part of the kernel that
accesses storage locations and manages data movement between storage devices
and memory.
File Control Layer - ANSWER-The FMS Layer that provides service functions for
manipulating files and directories, processes service calls from the command layer,
issues commands to the storage I/O control layer to interact with hardware, and
maintains the directory and storage allocation data structures. ( the bridge between
logical and physical views.)
The physical view is how the data is actually stored (i.e. on an SSD or harddisk).
