On-demand vs provisioned cost comparison in DynamoDB - Hands-On Comparison

On-demand vs Provisioned Cost Comparison in DynamoDB

📖 Scenario: You are managing a DynamoDB table for a small online store. You want to compare the monthly costs between using on-demand capacity mode and provisioned capacity mode based on your expected read and write requests.

🎯 Goal: Build a simple DynamoDB cost comparison by creating a data structure for request counts, setting capacity units, calculating costs for both on-demand and provisioned modes, and then outputting the cost comparison.

📋 What You'll Learn

Create a dictionary called monthly_requests with exact keys 'read' and 'write' and values 1000000 and 500000 respectively

Create variables read_capacity_units and write_capacity_units with values 50 and 25 respectively

Calculate provisioned_cost using the formula: (read_capacity_units * 0.00013 + write_capacity_units * 0.00065) * 730

Calculate on_demand_cost using the formula: (monthly_requests['read'] * 0.25 / 1000000 + monthly_requests['write'] * 1.25 / 1000000)

Create a dictionary called cost_comparison with keys 'provisioned' and 'on_demand' and their respective cost values

💡 Why This Matters

🌍 Real World

This project helps you understand how to estimate and compare costs for different DynamoDB capacity modes, which is important for budgeting and optimizing cloud expenses.

💼 Career

Database administrators and cloud engineers often need to analyze cost trade-offs between on-demand and provisioned capacity to make informed decisions for scalable and cost-efficient database management.

1

Create monthly request counts

Create a dictionary called monthly_requests with keys 'read' and 'write' and values 1000000 and 500000 respectively.

DynamoDB

# Create the monthly_requests dictionary with read and write counts
# Your code here

Need a hint?

Use curly braces to create a dictionary with the exact keys and values.

2

Set provisioned capacity units

Create two variables called read_capacity_units and write_capacity_units and set them to 50 and 25 respectively.

DynamoDB

monthly_requests = {'read': 1000000, 'write': 500000}
# Set read_capacity_units and write_capacity_units
# Your code here

Need a hint?

Assign the numbers 50 and 25 to the variables exactly as named.

3

Calculate provisioned and on-demand costs

Calculate provisioned_cost using the formula (read_capacity_units * 0.00013 + write_capacity_units * 0.00065) * 730 and calculate on_demand_cost using the formula (monthly_requests['read'] * 0.25 / 1000000 + monthly_requests['write'] * 1.25 / 1000000).

DynamoDB

monthly_requests = {'read': 1000000, 'write': 500000}
read_capacity_units = 50
write_capacity_units = 25
# Calculate provisioned_cost and on_demand_cost
# Your code here

Need a hint?

Use the exact variable names and formulas given to calculate costs.

4

Create cost comparison dictionary

Create a dictionary called cost_comparison with keys 'provisioned' and 'on_demand' and assign the variables provisioned_cost and on_demand_cost as their values.

DynamoDB

monthly_requests = {'read': 1000000, 'write': 500000}
read_capacity_units = 50
write_capacity_units = 25
provisioned_cost = (read_capacity_units * 0.00013 + write_capacity_units * 0.00065) * 730
on_demand_cost = (monthly_requests['read'] * 0.25 / 1000000 + monthly_requests['write'] * 1.25 / 1000000)
# Create cost_comparison dictionary
# Your code here

Need a hint?

Use curly braces to create the dictionary with the exact keys and assign the cost variables as values.