Level 6 — Module I — Operating Systems — Jul/Aug 2026

Module I • Level 6 • July/August 2026 • Written assessment

Work through each question before checking the answer. These revision answers are prepared for learners; they are not an official marking scheme.

Question 1

Give two ways monitoring tools help manage resources.

Answer

  • Display CPU, memory, disk and network utilisation to reveal bottlenecks.
  • Identify processes consuming excessive resources and provide evidence for adjusting workloads or investigating faults.

Question 2

Give four considerations before installing an OS.

Answer

  • Hardware compatibility and minimum requirements.
  • Application and peripheral-driver compatibility.
  • Backups and a plan for preserving/restoring user data.
  • Correct edition, licence, trusted installation media and installation/partitioning method.

Question 3

State three OS types based on user requirements.

Answer

  • Single-user OS.
  • Multi-user OS.
  • Real-time OS where responses must meet specified deadlines.

Question 4

Give two methods to restrict access to files.

Answer

  • Assign file-system permissions to authorised users/groups.
  • Encrypt sensitive files and protect the associated account/key.

Question 5

Give two OS clock roles.

Answer

  • Generates timer events used for scheduling, time slices and timeouts.
  • Maintains time information used for timestamps, elapsed-time measurement and system timekeeping.

Question 6

Give four formatting features for readable documents.

Answer

  • Clear heading styles and a consistent font size.
  • Appropriate paragraph spacing and line spacing.
  • Suitable alignment, margins and indentation.
  • Bullets/numbering or tables for structured information.

Question 7

Give two considerations when creating an email account.

Answer

  • Choose an appropriate provider/address for the intended use.
  • Use a strong unique password and configure supported recovery and multifactor authentication.

Question 8

Outline three disk-performance factors.

Answer

  • Seek/positioning time for mechanical disks.
  • Rotational latency for mechanical disks.
  • Transfer throughput, including interface bandwidth and workload. SSDs have no mechanical seek or rotational delay but still have access latency.

Question 9

Give four disk-storage management operations.

Answer

  • Allocates and releases storage blocks.
  • Creates/manages file systems and directories.
  • Tracks free and used disk space.
  • Schedules I/O and manages caching/buffering; it can also provide partition/volume tools.

Question 10

List four components of a database system.

Answer

  • Hardware/storage infrastructure.
  • DBMS software and applications.
  • Data and database metadata.
  • People/procedures, including administrators, developers and users.

Question 11

Outline three spreadsheet functions.

Answer

  • SUM adds numeric values in a range.
  • AVERAGE computes their arithmetic mean.
  • IF selects a result according to a logical condition.

Question 12

Differentiate a device driver and a peripheral controller.

Answer

A driver is OS software translating system requests into device-specific operations. A controller is hardware/firmware operating the peripheral and its data interface. The driver communicates with the controller through documented registers or protocols.

Question 13

Describe four presentation principles, two-level directory organisation, and three OS categories.

Answer

  • Keep each slide focused on a clear message.
  • Use readable text sizes, good contrast and a consistent layout.
  • Use relevant graphics/charts and avoid crowded slides.
  • Arrange a logical sequence and rehearse transitions/timing.

A master file directory contains an entry for each user. Each user has a user file directory containing their files. The path identifies the user directory and file, allowing different users to use the same filename without a collision; deeper subdirectories belong to a more general hierarchical structure.

  • Single-user systems serve one user at a time.
  • Multi-user/time-sharing systems support several users and allocate resources among them.
  • Real-time systems emphasise meeting deadlines for monitoring/control workloads.

Question 14

Use FCFS for P1(5,3), P2(3,7), P3(6,4), P4(2,8), P5(4,2), where each pair is arrival/burst seconds. Give the Gantt chart, waiting times, average wait, turnaround times and their average.

Answer

CPU idle 0–2; P4 2–10; P2 10–17; P5 17–19; P1 19–22; P3 22–26.
CPU idle 0–2; P4 2–10; P2 10–17; P5 17–19; P1 19–22; P3 22–26.
Step-by-step calculation

  1. Order by arrival: P4, P2, P5, P1, P3. The CPU is idle from 0 to 2 s.
  2. Start/finish intervals: P4 2–10, P2 10–17, P5 17–19, P1 19–22, P3 22–26.
  3. Waiting time = start − arrival. Turnaround = finish − arrival.
  4. Average waiting time = (14 + 7 + 16 + 0 + 13) / 5 = 10 s.
  5. Average turnaround time = (17 + 14 + 20 + 8 + 15) / 5 = 14.8 s.
Process Arrival Burst Start Finish Wait Turnaround
P1 5 3 19 22 14 17
P2 3 7 10 17 7 14
P3 6 4 22 26 16 20
P4 2 8 2 10 0 8
P5 4 2 17 19 13 15

Question 15

Explain paging with virtual memory, give two memory optimisations, and discuss five OS process-management roles.

Answer

Paging divides virtual memory into fixed-size pages and RAM into frames. A page table maps a process’s virtual pages to physical frames. Demand paging loads a required page when a page fault occurs. This supports isolation and programs larger than available RAM, but frequent page faults can reduce performance or cause thrashing.

  • Increase usable RAM or reduce the number of active applications so the working set fits in memory.
  • Use effective page-replacement/locality policies and avoid unnecessary memory allocation; fast backing storage reduces the cost of unavoidable faults.
  • Creates and terminates processes.
  • Maintains process control blocks and execution state.
  • Schedules CPU use and performs context switches.
  • Coordinates IPC and synchronisation.
  • Allocates/protects resources and handles blocked processes, exceptions and deadlock issues.

Question 16

Describe five process states with a diagram, then explain five implementation steps for swapping.

Answer

Five-state process lifecycle with admission, dispatch, preemption, I/O wait, event completion and exit transitions.
Five-state process lifecycle with admission, dispatch, preemption, I/O wait, event completion and exit transitions.
  • New: process creation.
  • Ready: runnable, waiting for CPU.
  • Running: executing instructions.
  • Waiting/Blocked: awaiting I/O or another event.
  • Terminated: finished or stopped.
  1. Select an eligible suspended process when memory pressure requires space.
  2. Save its context and memory image to backing storage.
  3. Release its RAM frames and record where the saved image is located.
  4. When it becomes eligible and memory is available, restore the image and update address mappings.
  5. Place it in the ready queue; the scheduler later restores its CPU context. Modern systems often page individual pages rather than swap an entire process.
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