How to Fix: Not able to extract performance data from .ETL file using xperf commands. getting error "Events were lost in this trace. Data may be unreliable ..."

Error: 'Events were lost in this trace. Data may be unreliable.' when trying to extract performance data from .ETL file using xperf commands affects Windows users who are unable to collect reliable performance logs. This issue can be frustrating as it prevents the user from obtaining accurate insights into system performance.

The error message suggests that the problem might be related to insufficient disk bandwidth for ETW (Event Tracing for Windows) logging, which requires increasing the minimum and maximum number of buffers and/or buffer size. However, this solution also increases memory pressure on the system.

🔍 Why This Happens

• The primary reason for this error is that xperf commands are not able to handle large .ETL files efficiently due to insufficient disk bandwidth. This can be caused by a variety of factors such as high volume of data, low disk performance, or inadequate logging configuration.
• Another possible cause could be issues with the ETW logging process itself, which might require further investigation and troubleshooting.

🛠️ Step-by-Step Verified Fixes

💡 Conclusion

To resolve the issue, try increasing disk buffers and buffer size using xperf commands or use Windows Performance Recorder (WPRUI.exe) to collect performance logs. If you are still experiencing issues, consider investigating further into ETW logging configuration and system resources.