A: With the Windows Performance Toolkit, you can collect detailed traces of what's happening in the OS when you run certain applications. You might want to troubleshoot, or just view, what's happening during an OS boot, and you can do that too.

If you've installed the Windows Performance Toolkit, you can use the xbootmgr command to setup tracing of a Windows boot. Use

xbootmgr -trace boot -traceFlags base+drivers+power+cswitch -numRuns 1 -resultPath C:\TEMP

Once you enter this command, the machine will be shut down and rebooted. Once the machine has rebooted and you logon, you might see a screen saying that the tool is still collecting, and asking if you want to let it continue and to allow the tool to elevate permissions. A warning will also be shown that says the trace could contain sensitive information, so use caution when sharing it.

After the tool's done, go to the folder you specified and several files will be present: a log file, a .cab file, and a very large .etl file that contains all the collected data. You can view the .etl file with xperfview—double-click the ETL file to automatically open it. (Opening it can take some time because xperfview has to parse the file.) You'll see a graphical view of the boot, including the logon. Information on the CPU, disk, services, processes, drivers, hard faults, and readyboot will all be shown to help identify where any delays in boot are occurring. Click the arrow on the left to select which graphs to display.