Flask web server on Raspberry Pi - Time & Space Complexity

Time Complexity: Flask web server on Raspberry Pi

O(n)

Understanding Time Complexity

When running a Flask web server on a Raspberry Pi, it is important to understand how the server handles requests as more users connect.

We want to know how the time to respond grows when more requests come in.

Scenario Under Consideration

Analyze the time complexity of the following Flask server code snippet.

from flask import Flask
app = Flask(__name__)

@app.route('/')
def home():
    return 'Hello from Raspberry Pi!'

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=5000)

This code starts a simple Flask web server that responds with a greeting message to each request at the home page.

Identify Repeating Operations

Identify the loops, recursion, array traversals that repeat.

• Primary operation: Handling each incoming web request one by one.
• How many times: Once per request, repeated as many times as users connect.

How Execution Grows With Input

Each new user request causes the server to run the handler function once.

Input Size (n requests)	Approx. Operations
10	10 handler calls
100	100 handler calls
1000	1000 handler calls

Pattern observation: The number of operations grows directly with the number of requests.

Final Time Complexity

Time Complexity: O(n)

This means the server work grows linearly with the number of requests it handles.

Common Mistake

[X] Wrong: "The server handles all requests instantly no matter how many come in."

[OK] Correct: Each request takes some time to process, so more requests mean more total work and longer total time.

Interview Connect

Understanding how a web server handles requests helps you explain real-world system behavior clearly and confidently.

Self-Check

What if the server handled multiple requests at the same time using threads? How would the time complexity change?