Notification messages vs data messages in Firebase - Performance Comparison

Time Complexity: Notification messages vs data messages

O(n)

Understanding Time Complexity

We want to understand how sending different types of Firebase messages affects the work done behind the scenes.

How does the number of operations change when sending notification messages versus data messages?

Scenario Under Consideration

Analyze the time complexity of sending notification and data messages using Firebase Cloud Messaging.

const messageNotification = {
  notification: { title: 'Hello', body: 'World' },
  token: userToken
};

const messageData = {
  data: { key1: 'value1', key2: 'value2' },
  token: userToken
};

admin.messaging().send(messageNotification);
admin.messaging().send(messageData);
    

This code sends one notification message and one data message to a user device.

Identify Repeating Operations

Look at what happens when sending messages repeatedly.

• Primary operation: Sending a message via admin.messaging().send() API call.
• How many times: Once per message sent, whether notification or data message.

How Execution Grows With Input

Each message sent requires one API call to Firebase servers.

Input Size (n)	Approx. API Calls/Operations
10 messages	10 API calls
100 messages	100 API calls
1000 messages	1000 API calls

Pattern observation: The number of API calls grows directly with the number of messages sent.

Final Time Complexity

Time Complexity: O(n)

This means sending messages takes time proportional to how many messages you send.

Common Mistake

[X] Wrong: "Notification messages are faster to send than data messages because they are simpler."

[OK] Correct: Both message types require one API call each, so sending time grows the same way for both.

Interview Connect

Understanding how message sending scales helps you design systems that handle many users efficiently.

Self-Check

What if you batch multiple messages in one API call? How would the time complexity change?