What caused the sudden 35% increase in failed DAG runs on Astronomer Cloud last week?

Introduction

The sudden 35% increase in failed DAG runs on Astronomer Cloud last week 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 our product ecosystem.

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 significant update or change to the Astronomer Cloud platform in the past week?

Why it matters: Recent changes often correlate with performance issues. Expected answer: Yes, there was a minor update to the scheduler. Impact on approach: If confirmed, we'd focus on the update's impact on DAG scheduling.

• Considering the scale of the issue, I'm wondering about its distribution. Is this increase in failed DAG runs uniform across all customers, or are certain segments more affected?

Why it matters: Helps identify if it's a global issue or specific to certain user groups. Expected answer: The issue is more prevalent among enterprise customers. Impact on approach: We'd prioritize investigating enterprise-specific configurations or usage patterns.

• Given the nature of DAGs, I'm curious about the failure points. At which stage of the DAG lifecycle are these failures primarily occurring?

Why it matters: Pinpoints the specific part of the process that's failing. Expected answer: Failures are mostly happening during DAG execution, not scheduling. Impact on approach: We'd focus on execution environment issues rather than scheduling problems.

• Thinking about external factors, have there been any significant changes in overall platform usage or load in the past week?

Why it matters: Helps rule out capacity or scaling issues. Expected answer: Usage has been consistent with normal patterns. Impact on approach: If confirmed, we'd shift focus from infrastructure scaling to other internal factors.

• Considering the importance of data integrity, has there been any change in how we're measuring or defining failed DAG runs?

Why it matters: Ensures we're not dealing with a measurement anomaly. Expected answer: No changes to metrics or definitions. Impact on approach: Confirms we're dealing with a real increase in failures, not a reporting issue.