We've confirmed that all systems are back to normal with no customer impact as of 05/19, 11:20 UTC. Our logs show the incident started on 05/19, 08:25 UTC and that during the 2 hours 55 minutes that it took to resolve the issue. Some customers using Azure Log Analytics and Azure Sentinel in West Europe region may have experienced intermittent log data latency and / or gaps. Additionally, users may have experienced incorrect alert activation during impacted period.
Root Cause: We determined that an instance of data ingestion pipeline reached an operational threshold due to high CPU usage, leading to the errors mentioned above.
Incident Timeline: 2 Hours & 55 minutes - 05/19, 8:25 UTC through 05/19, 11:20 UTC.
We understand that customers rely on Azure Log Analytics as a critical service and apologize for any impact this incident caused.