Using LatencyMon And DPC Latency Checker To Find Driver Problems

Drivers problem can occur frequently and IRQL conflicts are even worse. Using LatencyMon you can quickly identify your problem.

1. Download LatencyMon from here, scroll down and download the free home edition

2. Also download the DPC Latency Checker

3. Run LatencyMon by clicking the green arrow at the top

Let it run for 2 minutes

LatencyMon will display your hard pagefault, ISR execution time, DPC execution time, kernel timer latency and the highest measured kernel timer latency. You can get more information when you click on Stats

4. Click on the Drivers field at the top. Sort the drivers by highest execution time to find slow drivers. Also sort by ISR and DPC count. DPC stands for Deferred Procedure Calls, you can look it up on Wikipedia for a good explanation. In short, low priority tasks can be “deferred” (delayed) using a DPC. However, this can cause latency to go up.

Another important value to look at is your page fault number. A high number or latency indicates that your computer has a trouble with your memory management. It’s possible that illegal accesses, exceptions in programs can result in page faults. So, it’s possible that a program or corrupt driver is causing it. Thus, you can only speed up your PC if you find out what process/driver is causing the problems.