What factors led to the unexpected 30% increase in API response times for Xendit's XenPayment in the past 24 hours?

Introduction

The unexpected 30% increase in API response times for Xendit's XenPayment in the past 24 hours is a critical issue that demands immediate attention. This analysis will systematically identify, validate, and address the root cause while considering both short-term fixes and long-term implications for the product.

I'll approach this problem by first clarifying key details, ruling out external factors, and then diving deep into the product's user journey and metrics. From there, I'll generate data-driven hypotheses, conduct root cause analysis, and propose a comprehensive resolution plan.

Step 1

Clarifying Questions (3 minutes)

• Looking at the timing, I'm thinking this could be related to a recent deployment. Has there been any code push or infrastructure change in the last 48 hours?

Why it matters: Recent changes often correlate with performance issues. Expected answer: Yes, there was a minor update. Impact on approach: If yes, we'd focus on change-related hypotheses first.

• Considering the scale, I'm wondering if this affects all users equally. Are we seeing this 30% increase across all user segments and transaction types?

Why it matters: Helps narrow down potential causes and affected areas. Expected answer: It's affecting high-volume merchants more severely. Impact on approach: If segmented, we'd investigate specific user flows or data patterns.

• Given the API nature, I'm curious about our current load. Has there been any unusual spike in transaction volume or new integrations in the past week?

Why it matters: Unexpected load can strain systems and cause slowdowns. Expected answer: Transaction volume has been steady. Impact on approach: If no spike, we'd focus more on internal system issues rather than capacity problems.

• Thinking about potential data issues, has there been any change in how we're measuring or logging API response times?

Why it matters: Ensures we're dealing with a real problem, not a measurement artifact. Expected answer: No changes to measurement systems. Impact on approach: If changed, we'd need to validate our metrics before proceeding.