By default, client-side processing is not included in the performance metrics because client-side processing depends heavily on the end-user machine as well as on the Agent (or browser) used to parse the web page. Excluding client-side processing data from the results ensures that performance times are not skewed by how long the Agent takes to execute a script or parse a page.
To see the client-side processing time in results, select the Include client (non-network) time in results option when you provision a test. You can also edit an existing test to include this option.
Note: Client-side processing values may appear as visible gaps in the waterfall charts.