We've confirmed that all systems are back to normal with no customer impact as of 01/14, 01:12 AM UTC. Our logs show the incident started on 01/13, 11:45 PM UTC and that during the 1 hour and 27 minutes that it took to resolve the issue while 8034 subscription's of customers in WUS experienced intermittent data latency and incorrect alert activation.
Root Cause: The failure was due to An increase in incoming traffic for certain data types led to congestion on a backend service responsible for processing the incoming data.
Mitigation steps: The issue self-healed after the affected backend service auto-scaled to handle the increased volume of requests. Additionally we have worked on manually scaling up the service to avoid reoccurrence of the issue.
Incident Timeline: 1 Hours & 27 minutes - 01/13, 11:45 PM UTC through 01/14, 01:12 AM UTC
Latency increase: 60 minutes
We understand that customers rely on Application Insights as a critical service and apologize for any impact this incident caused.