Why has MessageBird's Voice API experienced a 20% increase in latency for calls originating from European data centers in the last 48 hours?

Introduction

MessageBird's Voice API has experienced a 20% increase in latency for calls originating from European data centers in the last 48 hours. This sudden performance degradation requires immediate attention and a thorough root cause analysis. I'll approach this issue systematically, focusing on identifying the underlying causes, validating hypotheses, and developing both short-term fixes and long-term solutions.

Step 1

Clarifying Questions (3 minutes)

• Given the sudden spike, I'm wondering about recent changes. Have there been any deployments or infrastructure updates in the past week?

Why it matters: Recent changes often correlate with performance issues. Expected answer: Yes, a minor update was pushed 3 days ago. Impact on approach: If confirmed, I'd prioritize investigating that update.

• Considering the geographic specificity, I'm curious about network changes. Has there been any modification to our European network infrastructure recently?

Why it matters: Network changes can significantly impact latency. Expected answer: No major changes, but there's been increased traffic from a new partner. Impact on approach: I'd look into capacity planning and potential bottlenecks.

• Thinking about external factors, have we seen any unusual patterns in call volume or user behavior from European customers?

Why it matters: Unexpected usage patterns can strain systems. Expected answer: Call volumes have been within normal ranges. Impact on approach: If true, I'd focus more on internal systems rather than user behavior.

• Regarding monitoring, are we seeing similar latency increases in other metrics or just in the Voice API?

Why it matters: Helps determine if this is an isolated issue or part of a broader problem. Expected answer: The issue seems confined to the Voice API. Impact on approach: I'd narrow my focus to Voice API specific components.

• Considering data integrity, has there been any change in how we measure or report latency in the last week?

Why it matters: Ensures we're dealing with a real issue, not a measurement anomaly. Expected answer: No changes to measurement systems. Impact on approach: If confirmed, I'd proceed with confidence in the data's accuracy.