Delay in notification deliveries

Final update

On November 12th, 2025, from 13:10 - 17:40 UTC, notifications service was degraded, showing an increase in web notifications latency and increasing delays in notification deliveries. A change to the notifications settings access path introduced additional load to the settings system, degrading its response times. This impacted both requests to web notifications (with p99 response times as high as 1.5s, while lower percentiles remained stable) and notification deliveries, which reached a peak delay of 24 minutes on average. System capacity was increased around 15:10 UTC and the problematic change was fully reverted soon after that, restoring the latency of web notifications and increasing notification delivery throughput, decreasing the delay in notification deliveries. The notification queue was fully emptied around 17:40 UTC. We are working to adjust capacity in the affected systems and to improve the time needed to address these capacity issues.

1. Resolved · Nov 12, 17:39 UTC
   On November 12th, 2025, from 13:10 - 17:40 UTC, notifications service was degraded, showing an increase in web notifications latency and increasing delays in notification deliveries. A change to the notifications settings access path introduced additional load to the settings system, degrading its response times. This impacted both requests to web notifications (with p99 response times as high as 1.5s, while lower percentiles remained stable) and notification deliveries, which reached a peak delay of 24 minutes on average. System capacity was increased around 15:10 UTC and the problematic change was fully reverted soon after that, restoring the latency of web notifications and increasing notification delivery throughput, decreasing the delay in notification deliveries. The notification queue was fully emptied around 17:40 UTC. We are working to adjust capacity in the affected systems and to improve the time needed to address these capacity issues.