How Global Payments Inc. improved their tail latency using request hedging with Amazon DynamoDB

Global Payments Inc. (GPN) improved their DynamoDB-powered credit card authorization platform's performance by implementing request hedging, reducing tail latency by 30%.

• Request hedging involves sending a duplicate request if the initial request exceeds a specified time threshold
• Tested different delta values to optimize latency and duplicate request rates
• Best performance achieved at 80th percentile delta value, with:
  • 29% latency improvement
  • 8% duplicate request rate
• Suitable for high-throughput systems with strict low-latency requirements
• Differs from standard SDK retry behavior by monitoring both original and duplicate requests simultaneously

The approach helps manage tail latency in distributed systems, particularly for mission-critical financial transactions processing millions of requests daily.