ICT Operating System Fundamentals 3 — Questions and Answers
Question 1: What is 'thrashing' in an operating system?
- Excessive CPU overclocking
- A state where the OS spends more time paging than executing processes (Correct answer)
- Rapid context switching between threads
- Disk fragmentation causing slow reads
Correct answer: A state where the OS spends more time paging than executing processes
Thrashing occurs when a system has too many processes competing for too few memory frames, causing constant page faults.
Question 2: What is the main difference between a hard link and a soft (symbolic) link?
- Hard links work across file systems; soft links do not
- Soft links point directly to inode data; hard links use a name alias
- Hard links point to the inode; soft links point to the filename path (Correct answer)
- There is no practical difference
Correct answer: Hard links point to the inode; soft links point to the filename path
A hard link directly references the file's inode, while a symbolic link stores the path to another file name.
Question 3: Which OS component is responsible for translating high-level I/O calls into device-specific operations?
- Device driver (Correct answer)
- File system
- Virtual memory manager
- Process scheduler
Correct answer: Device driver
Device drivers provide an abstraction layer that translates generic OS I/O requests into hardware-specific commands.
Question 4: In the context of CPU scheduling, what is 'aging'?
- Gradually increasing the priority of waiting processes to prevent starvation (Correct answer)
- Reducing CPU speed when idle
- Swapping old processes to disk
- Removing processes that have run too long
Correct answer: Gradually increasing the priority of waiting processes to prevent starvation
Aging gradually increases the priority of processes that have been waiting a long time, preventing starvation.
Question 5: What does 'copy-on-write' (COW) enable in process forking?
- Immediate full duplication of parent memory
- Parent and child share memory pages until one modifies them (Correct answer)
- Child process writes to disk instead of RAM
- Automatic backup of forked process data
Correct answer: Parent and child share memory pages until one modifies them
Copy-on-write defers page copying until either the parent or child process actually modifies a shared page.
Question 6: Which RAID level provides both striping and mirroring?
- RAID 0
- RAID 1
- RAID 5
- RAID 10 (Correct answer)
Correct answer: RAID 10
RAID 10 combines striping (RAID 0) for performance and mirroring (RAID 1) for redundancy.
Question 7: What is the role of the 'inode' in a Unix-like file system?
- It stores the file's actual content data
- It contains metadata about a file such as permissions, size, and disk block locations (Correct answer)
- It is the directory entry with the file's name
- It is a network interface identifier
Correct answer: It contains metadata about a file such as permissions, size, and disk block locations
An inode stores file metadata (permissions, timestamps, size, block pointers) but not the file name or content.
ICT Operating System Fundamentals 3
What is 'thrashing' in an operating system?