Which metrics related to the startup time are collected by Bitmovin Analytics?

This is a list of frequently asked questions about bitmovin analytics and its collected metrics.

STARTUPTIME - End-to-end delay of a playback session
PLAYER_STARTUPTIME - Duration of player setup
How long did it take the player to load. Essentially the duration it took until the user could start playback.

This is measured as the time elapsed between analytics.register(player) is called and the player emitting the ON_READY event.

VIDEO_STARTUPTIME - Time to stream start
From the time the user expressed intent to watch the video until the first frame was displayed on his screen.

This is measured as the time between ON_PLAY to the first ON_TIME_CHANGED event being fired.

PAGE_LOAD_TIME - Time it took the page to load
Not directly related to video - PAGE_LOAD_TIME is the total amount of time it took for the player to report ready, counted from the navigationStart. This metric is useful if you want to measure if improvements on the surrounding page positively or negatively impacted the total load time of the page until the user is theoretically able to start video playback.

PAGE_LOAD_TYPE - Was the page loaded in the foreground or background?
When a user opens a link in a new tab, certain browsers like Chrome will not allocate as many resources to the loading as to foreground tabs. This means that timers become unreliable and certain elements of a page (like the Media Source Extensions) are not loaded until the user brings the tab into the foreground.

This impacts analytics as the ON_READY event will only be fired once the page comes back into the foreground. This obviously skews any startup performance data collected as users that keep the background tab open for a few days will have a PLAYER_STARTUPTIME of days, not milliseconds.

To address this, bitmovin analytics has a field which can be filtered for called PAGE_LOAD_TYPE

  • 1: Foreground
  • 2: Background

DRM_LOAD_TIME - Time it took for the DRM Licensing requests to finish. In the Dashboard it's being presented as a separate bar next to video startup time and player startup time as it's not a blocking operation but something that's usually ongoing in the background while the player is also fetching video segments/starting up the streams. Therefore a high DRM load time indicates that the video startup time might be impacted by the DRM licensing server, but inversely optimising the DRM load time might not lead to an equal reduction in video startup time.