Provider
UpstashIncident detail
Fly.io Upstash Redis service distruption (FRA region)
Fly.io Upstash Redis service distruption (FRA region)
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Investigating
Some databases may experience increased latency or timeouts in Fly.io’s FRA region.
Investigating
We are continuing to investigate the issue.
Investigating
We are working with Fly team to investigate the root cause.
Resolved
The incident has been resolved. We are working with Fly team on RCA.
Resolved
On May 12th and 13th at various times, a subset of Upstash Redis instances on [Fly.io](http://Fly.io) experienced intermittent hangs and elevated error rates. The Redis process would stall inside a logging syscall — alive but not making progress — which made the issue hard to spot from our usual telemetry. After investigating with Fly's team, we identified the root cause as a bad interaction between a recent guest kernel update on Fly's newer machines and an upstream Cloud Hypervisor bug \([cloud-hypervisor#7672](https://github.com/cloud-hypervisor/cloud-hypervisor/issues/7672)\) affecting log writes from inside the VM. We mitigated by disabling the affected logging paths, and Fly has since rolled out a hypervisor-side patch, fully resolving the issue. No data was lost. Sorry for the disruption.