DynamoDB at Scale: Global Read and Write

This guide explains how to scale Amazon DynamoDB for high throughput and global availability with minimal setup.

1. Key Features for Scaling

• Auto Scaling – Automatically adjusts read/write capacity based on traffic.
• On-Demand Mode – Pay per request, scales instantly without capacity planning.
• Global Tables – Multi-Region replication for low-latency reads/writes.

2. Setup Steps

Step 1: Create DynamoDB Table

• Go to DynamoDB > Create Table.
• Set Primary Key (Partition key or Partition + Sort key).
• Choose On-Demand (recommended for unpredictable workloads) OR Provisioned with Auto Scaling.

Step 2: Enable Auto Scaling (if Provisioned Mode)

• Enable Read/Write Auto Scaling.
• Set target utilization (e.g., 70%).
• DynamoDB adjusts capacity units automatically.

Step 3: Enable Global Tables

1. Go to Table > Global Tables > Add Region.

2. Select additional AWS Regions.

3. DynamoDB will replicate data across Regions with multi-active writes.

   • All Regions can read/write simultaneously.
   • Conflict resolution is last-writer-wins based on timestamp.

Step 4: Optimize for Scale

• Use partition keys with high cardinality to distribute load.
• Use DAX (DynamoDB Accelerator) for caching if read-heavy.
• Monitor with CloudWatch metrics (throttle events, consumed capacity).

3. Verification

• Insert data in Region A → Verify it appears in Region B.
• Perform read/write from multiple Regions with low latency.

4. Notes

• Global tables support multi-Region, multi-master replication.
• Use IAM roles to control access at scale.
• Combine with API Gateway + Lambda for serverless global apps.