Performance testing basics in Testing Fundamentals - Test Execution Trace

Test Overview

This test simulates multiple users accessing a website at the same time to check if the website stays fast and stable. It verifies that the website responds within an acceptable time under load.

Test Code - Python threading with requests

Testing Fundamentals

import time
from threading import Thread
import requests

responses = []

# Function to simulate a user sending a request
def simulate_user(url):
    start = time.time()
    response = requests.get(url)
    end = time.time()
    responses.append((response.status_code, end - start))

# URL to test
url = 'https://example.com'

# Number of simulated users
num_users = 5

threads = []
for _ in range(num_users):
    thread = Thread(target=simulate_user, args=(url,))
    threads.append(thread)
    thread.start()

for thread in threads:
    thread.join()

# Check all responses
for status, duration in responses:
    assert status == 200, f"Expected status 200 but got {status}"
    assert duration < 2, f"Response took too long: {duration} seconds"

Execution Trace - 6 Steps

Step	Action	System State	Assertion	Result
1	Test starts	Test script is ready to run	-	PASS
2	Starts 5 threads to simulate 5 users sending requests to https://example.com	5 threads running, each sending HTTP GET request	-	PASS
3	Each thread sends a GET request and records response status and time taken	Responses collected with status codes and durations	-	PASS
4	Main thread waits for all user threads to finish	All threads completed	-	PASS
5	Check each response status is 200 and response time is less than 2 seconds	All responses verified	Assert status == 200 and duration < 2 seconds for each response	PASS
6	Test ends with all assertions passed	Test completed successfully	-	PASS

Failure Scenario

Failing Condition: One or more responses have status code not equal to 200 or response time exceeds 2 seconds

Execution Trace Quiz - 3 Questions

What does the test simulate in performance testing?

A Multiple users accessing the website at the same time

B A single user clicking buttons repeatedly

C Checking spelling errors on the website

D Verifying the website layout on mobile devices

Key Result

Performance tests should simulate real user load and verify both response correctness and response time limits to ensure the system can handle expected traffic.