operating_system_journal

Week 3 – Application Selection for Performance Testing

Student Name: Mehedi Hasan Rakib
Student ID: A00022820
Module: CMPN202 – Operating Systems

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Introduction

This week focuses on selecting appropriate applications to evaluate operating system performance under different workload types. Each application is chosen to stress a specific system resource, allowing meaningful performance analysis and comparison in later weeks.

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Application Selection Matrix

Workload Type	Application	Justification
CPU-intensive	stress-ng	Generates controlled CPU load to analyse processor utilisation and scheduling behaviour.
Memory-intensive	stress-ng (vm test)	Stresses memory allocation to observe RAM usage and swapping behaviour.
Disk I/O-intensive	fio	Benchmarks disk read/write throughput and I/O latency.
Network-intensive	iperf3	Measures network bandwidth and latency in client-server mode.
Server application	nginx	Simulates a real-world server workload with concurrent connections.

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Installation Documentation (SSH-based)

All applications were installed on the Ubuntu Server using secure SSH access from the Windows workstation.

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Update System Packages and Install Applications

bash sudo apt update sudo apt install stress-ng -y sudo apt install fio -y sudo apt install iperf3 -y sudo apt install nginx -y

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Expected Resource Usage Profiles

CPU-intensive workload

• High CPU utilisation across all available cores
• Increased scheduler activity and context switching

Memory-intensive workload

• Rapid allocation and deallocation of memory
• Increased swap usage if RAM limits are exceeded

Disk I/O-intensive workload

• High read/write operations
• Increased I/O wait times during peak usage

Network-intensive workload

• High bandwidth usage
• Observable latency under load

Server application workload

• Moderate CPU and memory usage
• Multiple worker processes handling concurrent connections

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Monitoring Strategy

The following command-line tools will be used in later weeks to monitor system performance:

• top / htop – CPU and memory usage
• free -h – Memory utilisation
• vmstat – System activity
• iostat – Disk I/O performance
• ss and ip – Network statistics

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Weekly Reflection

This week improved my understanding of how different workloads stress specific operating system resources. Selecting appropriate applications ensures that performance testing is structured, measurable, and relevant to real-world server environments.