**Summary:** We experienced intermittent latency with Google Drive **Description:** The issue with Google Drive has been resolved for all affected customers as...

What caused it: Google Drive's root cause analysis

# Incident Report Summary On Wednesday, 16 September 2026, Google Drive experienced an issue where a subset of traffic was dropped for a duration of 39 minutes. We sincerely apologize for the disruption this incident caused to your business. We recognize the critical role Google Cloud plays in your operations and deeply regret the impact on your services. Our engineering teams have resolved the issue and have taken immediate measures to address the incident. Additionally, engineering teams are conducting a comprehensive review of the incident to fully address the root cause and prevent the recurrence of such an event. Root Cause This incident was triggered by a planned capacity test which temporarily reduced Google Drive's serving capacity. The sequence of events leading to the impact was as follows: Engineers initiated a routine capacity test, causing Drive to operate with reduced capacity. The remaining available capacity was insufficient to handle peak user traffic. As traffic exceeded capacity, the capacity protection system was triggered and began blocking legitimate Drive requests. Remediation and Prevention The issue was detected on Wednesday 16 September 2026 at 7:03 via our automated outage detector systems that monitor error rates and user queries. To mitigate the symptoms, Google engineers initiated an immediate rollback of the capacity test to restore serving capacity. Additionally, engineers upsized available capacity and updated the system load limit threshold to add more capacity headroom. Google is committed to preventing a repeat of this issue in the future and is completing the following immediate actions: - Resilience and Resourcing: Ensure sufficient buffer capacity is available globally during capacity tests. - Address the Root Cause: Engineering is conducting a comprehensive review of capacity modeling and protection thresholds to ensure they correctly account for capacity tests during peak traffic periods. Detailed Description of Impact On Wednesday, 16 September 2026, from 07:03 to 07:43 US/Pacific, customers were unable to access Google Drive. A subset of overall traffic to Google Drive was dropped during this window. Affected users experienced failures, elevated latency, or timeouts when attempting to access, upload, or sync files in Google Drive. Additional Information for Customers: Customers who experienced impact during this window are encouraged to review their deployment logs. If you continue to see lingering issues beyond t...

Read the full postmortem from Google Drive