What is Startup Impact in Task Manager and How is it Calculated?

You would have noticed a column named “Startup Impact” in Task Manager’s Startup tab in Windows 8 and higher. But what does “Startup Impact” mean and how is it assessed?

task manager startup impact

Task Manager Startup tab lists all startup apps loading from Run, RunOnce registry keys and from the user’s Startup folder, and allows the user to disable unneeded startup programs. Task Manager also displays the “Startup Impact” of each startup program. The Impact rating is based on the program’s CPU and disk usage at startup.

Per Microsoft: Startup apps (Windows), the following criteria is applied to determine the Startup Impact values for each startup entry.

  • High impact – Apps that use more than 1 second of CPU time or more than 3 MB of disk I/O at startup
  • Medium impact – Apps that use 300 ms – 1000 ms of CPU time or 300 KB – 3 MB of disk I/O
  • Low impact – Apps that use less than 300 ms of CPU time and less than 300 KB of disk I/O

So, OneDrive.exe (OneDrive client) in the screenshot above clearly qualifies for being in the “High Impact” category.

It shows the Impact as “Not measured” for entries pointing to a missing file, or haven’t clocked a single run yet, via Startup. Impact shows up as “None” for disabled entries in the Startup tab.

How does Windows Measure the “Startup Impact”?

The “Startup Impact” is actually calculated by the Windows Diagnostic Infrastructure. Windows runs a boot trace every time you start your computer, and the results of which are stored in an event trace file named “Bootckcl.etl” in this directory:


task manager startup impact

If you want to analyze this file, you need Windows Performance Analyzer (WPA) installed in your system. This tool is part of the Windows Assessment and Deployment Kit which can be downloaded from the Microsoft site. WPA is an extremely useful tool to troubleshoot slow boot and performance issues in the system.

Based on the boot trace, Windows also generates separate XML files in the “LogFiles\StartupInfo” directory which contains details about each startup item, their start time, CPU time as well as the Disk Usage at startup for each user. The XML file is separate for each user, and the file name includes the user account’s SID, such as the following:


task manager startup impact

You can open these files using Notepad, and check out the readings there. To find the appropriate file for your user account, you need to first find your user account SID by typing whoami /user in a Command Prompt window. There are several ways to find out your SID, but whoami is probably the easiest.

task manager startup impact
CPU usage units in microseconds. 1000 μs is 1 ms

This information is what is queried and used by Task Manager to populate the “Startup Impact” column.


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3 thoughts on “What is Startup Impact in Task Manager and How is it Calculated?”

  1. So what is wrong with my computer if startup impact for every enabled program simply reads “not measured”? Also, my computer does not go to explorer on startup but instead a command window and black screen and I have to type “explorer” into that command window to start up Windows 10 explorer. I did have malwarebytes delete a file that it had quarantined which I should have written down the name of but I did not! So what file could be causing both problems (the absence of which file?)

    • @Aaron: Must be caused by a missing Userinit registry value. Pls upload your Autoruns log file and share the link here. I’ll take a look.

  2. Task manager says not measured for every entry after updating windows. I have already tried couple of common solutions online but no luck. Any help?


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