Avoid Lost Events

Applies To: Windows 8, Windows 8.1

In Windows® Performance Recorder (WPR), some applications generate so many events that Event Tracing for Windows (ETW) cannot keep up with the logging frequency. This problem manifests as lost events in the recordings. The problem can lead to analysis difficulties or erroneous conclusions because of incomplete data.


By default, WPR uses paged memory for buffers. To set WPR to use non-paged memory for buffers, set the NonPagedMemory attribute to true for the provider. For more information about how to create a custom profile, see Authoring Recording Profiles and 2. System and Event Provider Definitions.

You can help prevent WPR from losing ETW buffers or events in the following ways:

  • Use larger buffers to enable more efficient disk I/O when WPR writes the buffers to disk.

  • Count requests for the data collection the first time that you use a particular buffer configuration on a computer.

  • Use the command-line recordTempTo option to record to a different location than the default.

  • Increase the number of buffers.

  • Simplify the scenario that you are testing, or select fewer profiles.

  • Free disk space on the system drive.

  • Use advanced hardware to collect the data; for example, use a disk subsystem that has higher throughput. This is the last option to consider. You can usually avoid losing events by carefully selecting the providers to enable and the buffers to use.

See Also


Change the Logging Mode
Change the Detail Level


Recording Profiles
Logging Mode
Detail Level

Other Resources

WPR How-to Topics
Sessions (Windows Drivers)