IL-0557 Storj · 2025-08-07database
Database transaction locks piled up on Storj's US1 satellite, and uploads and downloads failed with timeouts for 2 hours
On 7 August 2025 an exceptionally high volume of simultaneous uploads to the same objects reached the Storj US1 satellite. The database transactions for these uploads contended with each other, and because a transaction holds locks on the data it touches until it is committed or rolled back, locks built up from 21:04 UTC. Long-running transactions increased, requests timed out and connection pools were exhausted. The on-call team was paged at 21:14. To stop contention errors from growing in a cascade, Storj periodically reset the state of connections, and a fix was in place at 21:55. Error rates rose again at 22:31, returned to normal at 22:45, and operations were fully restored at 23:05. Storj then changed code to remove the sources of contention between transactions.
- Severity
- –
- Scope
- Storj US1 satellite uploads and downloads (US1 Linksharing, Gateway, Select)
- Users affected
- Customers and applications using the US1 satellite
- Region
- US1
- Time to detect
- 10m
- Time to resolve
- 2h 1m
Symptoms
From 21:04 UTC on 7 August 2025, database transaction locks on the Storj US1 satellite started to increase, and upload and download requests began to fail. The on-call team was paged at 21:14 UTC.
As long-running transactions grew, requests timed out and connection pools were exhausted. After a fix at 21:55 UTC error rates came down, rose again at 22:31, and returned to normal at 22:45; operations were fully restored at 23:05 UTC. The AP1 and EU1 satellites were not affected.
Symptom Lock contention or deadlockIntermittent timeoutsConnection pool exhaustionHigh error rate
Root cause
Root cause Capacity exhaustion
- Trigger
- An unusually high volume of concurrent uploads to the same objects reached the US1 satellite.
Detection
The on-call team was paged at 21:14 UTC, ten minutes after database transaction locks began to rise.
Remediation
- Reset the state of connections periodically to keep contention errors from growing in a cascade
Action items
- Remove the sources of contention between database transactions with code changes
- Add monitoring and alerts for increased levels of database locks
- Look for further process and system improvements, including tools that reduce or remove the need for manual maintenance
Lessons
–
Sources
- https://status.storj.io/incidents/3q9z06kvylvv · official-status · archived copy
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