How to Use the Performance Monitor (PerfMon) to Track CPU Spikes in Windows 11

What is Performance Monitor?

When a Windows 11 PC suddenly becomes sluggish, freezes, or experiences sudden fan noise, most users open the Task Manager to see what is consuming their resources. However, Task Manager only provides a real-time snapshot of the current moment. If the CPU spike happens intermittently while you are away from the computer or playing a full-screen game, Task Manager is virtually useless.

Performance Monitor (PerfMon) is a deeply integrated administrative tool in Windows 11 that allows you to record system performance metrics over a prolonged period. By creating a custom Data Collector Set, you can log exactly which process caused a CPU spike at a specific timestamp, even if it happened hours ago.

Step 1: Open Performance Monitor

Because it is an administrative tool, PerfMon is hidden from the standard Settings menu.

1. Press the Windows Key + R to open the Run dialog box.
2. Type perfmon and press Enter.
3. You may be prompted by User Account Control (UAC) to grant administrator privileges. Click Yes.

Step 2: Create a Custom Data Collector Set

To track intermittent CPU spikes, you need to create a log that records data automatically in the background.

1. In the left sidebar of Performance Monitor, expand the Data Collector Sets folder.
2. Right-click on User Defined.
3. Select New > Data Collector Set.
4. Give your set a descriptive name (e.g., “CPU Spike Tracker”).
5. Select the Create manually (Advanced) radio button and click Next.
6. Under “Create data logs,” check the box for Performance counter and click Next.

Step 3: Add the Correct CPU Counters

Now, you must tell the tool exactly what data to monitor.

1. Click the Add… button. A large window containing hundreds of available metrics will open.
2. Scroll down the list and expand the Processor category by clicking the small down arrow next to it.
3. Select % Processor Time.
4. In the “Instances of selected object” box below, select _Total and click the Add >> button.
5. Now, to find out which specific application is causing the spike, scroll up to the Process category and expand it.
6. Select % Processor Time again.
7. In the Instances box, select <All instances> and click Add >>.
8. Click OK to close the Add Counters window.

Change the Sample interval to 5 seconds (this ensures the log file does not become overwhelmingly massive while still capturing sudden spikes). Click Next, then Finish.

Step 4: Start the Tracker and Analyze the Log

To begin monitoring your system, right-click your newly created “CPU Spike Tracker” under the User Defined folder and select Start. You can now minimize PerfMon and use your PC normally until the performance issue occurs.

Once you experience the lag or CPU spike, return to PerfMon, right-click the tracker, and select Stop.

To view the results:

1. In the left sidebar, expand the Reports folder, then User Defined, and select your tracker.
2. A graph will appear displaying the recorded data.
3. Look for massive vertical spikes in the graph. Click on a spike to highlight it.
4. Look at the table below the graph to see exactly which process (e.g., a rogue background updater or an antivirus scan) corresponds to that specific spike in CPU usage.