Database instance write performance impacted

What happened

Between August 22 and August 28, 2025, a performance issue affected some of our database services following a recent update. Our team quickly responded and discovered that the problem was due to a bug in the latest update, which caused certain memory settings to be incorrectly configured. We promptly applied the previous version of those settings to stabilize the affected databases. By August 28, all databases were successfully transferred to a new, stable version, and the incident was fully resolved.

The issue was caused by a misconfiguration in the system's data processing module. Specifically, an incorrect parameter setting in the data pipeline led to a bottleneck, which slowed down the processing speed. This misconfiguration affected the way data was being queued and processed, resulting in delays. Our technical team has identified the root cause and implemented a fix to ensure that the data pipeline operates efficiently, preventing future occurrences of this issue.

How the service was affected

Some customers reported a performance change on their instance. 

What we are doing now

Neo4j remains committed to providing reliable service and is implementing additional safeguards to prevent similar incidents in the future.

New mitigations being deployed:

• Enhancing our monitoring systems to detect similar issues faster
• Implementing additional automated checks to prevent service disruptions
• Improving our service resilience to handle similar scenarios
• Introducing dynamic configuration management to ensure seamless updates
• Enabling multiple configuration defaults to better manage database priorities
• Improving notification systems for faster response to potential issues
• Enhancing our tools to streamline database management and transfers