Hash slots distribution in Redis - Mini Project: Build & Apply

Hash Slots Distribution in Redis Cluster

📖 Scenario: You are managing a Redis cluster that distributes keys across multiple nodes using hash slots. Understanding how keys map to hash slots helps in balancing the load and troubleshooting data distribution.

🎯 Goal: Build a simple Redis key-to-hash slot mapping using a dictionary to simulate hash slot distribution. You will create the data structure, configure the number of hash slots, compute the hash slot for each key, and finalize the distribution map.

📋 What You'll Learn

Create a dictionary called keys with these exact entries: 'user:1001': 'Alice', 'user:1002': 'Bob', 'order:5001': 'Pending', 'order:5002': 'Shipped'

Create a variable called total_slots and set it to 16384

Create a dictionary called slot_distribution that maps each key to its hash slot using the formula: hash(key) % total_slots

Add a final line that sets a variable distribution_complete to True

💡 Why This Matters

🌍 Real World

Redis clusters use hash slots to distribute data evenly across multiple nodes, improving performance and scalability.

💼 Career

Understanding hash slot distribution is essential for database administrators and backend developers working with Redis clusters to optimize data storage and retrieval.

1

Create the initial keys dictionary

Create a dictionary called keys with these exact entries: 'user:1001': 'Alice', 'user:1002': 'Bob', 'order:5001': 'Pending', 'order:5002': 'Shipped'

Redis

# Create the keys dictionary with exact entries
# Your code here

Need a hint?

Use curly braces {} to create a dictionary with the exact key-value pairs.

2

Set the total number of hash slots

Create a variable called total_slots and set it to 16384

Redis

keys = {'user:1001': 'Alice', 'user:1002': 'Bob', 'order:5001': 'Pending', 'order:5002': 'Shipped'}
# Create total_slots variable and set it to 16384
# Your code here

Need a hint?

Assign the integer 16384 to the variable total_slots.

3

Compute hash slot for each key

Create a dictionary called slot_distribution that maps each key in keys to its hash slot using the formula: hash(key) % total_slots

Redis

keys = {'user:1001': 'Alice', 'user:1002': 'Bob', 'order:5001': 'Pending', 'order:5002': 'Shipped'}
total_slots = 16384
# Create slot_distribution dictionary mapping keys to hash slots
# Your code here

Need a hint?

Use a dictionary comprehension to map each key to hash(key) % total_slots.

4

Mark distribution as complete

Add a final line that sets a variable distribution_complete to True

Redis

keys = {'user:1001': 'Alice', 'user:1002': 'Bob', 'order:5001': 'Pending', 'order:5002': 'Shipped'}
total_slots = 16384
slot_distribution = {key: hash(key) % total_slots for key in keys}
# Set distribution_complete to True
# Your code here

Need a hint?

Simply assign True to the variable distribution_complete.