Incomplete Boot Duration Metrics
uberAgent collects detailed information about each machine boot process. This is governed by the on-demand metric BootDetail which is enabled by default and can be adjusted through uberAgent’s configuration.
Sometimes the collected BootDetail metrics are incomplete and not all data is visualized in the Boot Duration dashboard. After reviewing uberAgent’s logfile you may find entries like this:
OnOffTransition,Data from boot trace file missing! The following analysis may be incomplete. Lost events: 1000000, lost buffers: 0. Typical cause: insufficient disk bandwidth
uberAgent does not add any load to the boot processes. It uses logs that are created by Windows anyway. Depending on the complexity of the boot process (e.g. installed drivers, applications) the pre-defined number of buffers, as well as the buffer size, are insufficient. You can adjust the number of buffers and the buffer size within the endpoint’s registry:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Diagnostics\Performance\BootCKCLSettings "BufferSize" "MaximumBuffers" "MinimumBuffers"
Increase all three values until the lost events message disappears in uberAgent’s logfile. Doubling the default values is a good starting point.