DPC Latency Checker (DPC)

[Maxstar]

This might be a helpful tool for the hardware experts, it's from the developer(s) of DDU.

We’re excited to announce the release of our latest tool: DPC Latency Checker – a simple yet powerful utility designed to help you identify and diagnose Deferred Procedure Call (DPC) latency issues on Windows systems.

Whether you're a gamer, content creator, or audio/video professional, high DPC latency can cause unwanted dropouts, glitches, and input lag. With DPC Latency Checker, you can easily monitor your system's real-time latency performance and pinpoint problematic drivers or processes.

Summary of features and functionality:
- Ideal for troubleshooting crackling or dropouts / input lag or stuttering
- Real-time DPC latency monitoring
- Clear graphical display of latency over time
- Lightweight and efficient — no installation required
- Supports Windows 10 and 11

Sources:
- Download DPC Latency Checker (DPC) 1.0.0.5
- DPC Latency Checker (DPC) V1.0.0.5 Released. - Wagnardsoft Forum

Use the following command to write the result to a log file (for a period of time) instead of monitoring the results into the command line window. Attached the result from an older laptop which i'm using for testing purposes.

dpclatency.exe > "%userprofile%\desktop\DPC.log"

Example of the output:

######################################################################################
WARNING: 2025-04-19 13:21:46.513 [DPC] CPU: 0, Routine: 0xFFFFF8000F4B9E70, Offset: 0x19E70, Driver: ACPI.sys (10.0.26100.1 (WinBuild.160101.0800)), Base: 0xFFFFF8000F4A0000, Size: 876544, Duration: 503,40 µs
######################################################################################
Critical Threshold-Exceeding Events:
No critical events recorded.
######################################################################################
CRITICAL: 2025-04-19 13:21:49.538 Long [TimerDPC] detected: CPU 1, Routine: 0xFFFFF8007D25BA90, Offset: 0x45BA90, (Driver: ntoskrnl.exe (10.0.26100.3775 (WinBuild.160101.0800)), Base: 0xFFFFF8007CE00000, Size: 21295104, Duration: 1087,90 µs
WARNING: 2025-04-19 13:21:51.553 [DPC] CPU: 0, Routine: 0xFFFFF8000F4B9E70, Offset: 0x19E70, Driver: ACPI.sys (10.0.26100.1 (WinBuild.160101.0800)), Base: 0xFFFFF8000F4A0000, Size: 876544, Duration: 503,40 µs
######################################################################################
Critical Threshold-Exceeding Events:
+-----------------+-------------+----------+--------------+--------------------+--------------------+------------------+----------------+--------+
| Driver          | Event Type  | Offset   | Max Critical Duration | Routine            | Base Address       | Version          | Critical Count | Total  |
+-----------------+-------------+----------+--------------+--------------------+--------------------+------------------+----------------+--------+
| ntoskrnl.exe    | TimerDPC    | 0x45BA90 | 1087,90 µs   | 0xFFFFF8007D25BA90 | 0xFFFFF8007CE00000 | 10.0.26100.3775  | 1              | 1      |
+-----------------+-------------+----------+--------------+--------------------+--------------------+------------------+----------------+--------+
######################################################################################
WARNING: 2025-04-19 13:22:00.654 [DPC] CPU: 0, Routine: 0xFFFFF8000F4B9E70, Offset: 0x19E70, Driver: ACPI.sys (10.0.26100.1 (WinBuild.160101.0800)), Base: 0xFFFFF8000F4A0000, Size: 876544, Duration: 500,10 µs
WARNING: 2025-04-19 13:22:00.654 [DPC] CPU: 0, Routine: 0xFFFFF8000F4B9E70, Offset: 0x19E70, Driver: ACPI.sys (10.0.26100.1 (WinBuild.160101.0800)), Base: 0xFFFFF8000F4A0000, Size: 876544, Duration: 500,90 µs
WARNING: 2025-04-19 13:22:00.654 [DPC] CPU: 0, Routine: 0xFFFFF8000F4B9E70, Offset: 0x19E70, Driver: ACPI.sys (10.0.26100.1 (WinBuild.160101.0800)), Base: 0xFFFFF8000F4A0000, Size: 876544, Duration: 548,50 µs
######################################################################################

===== FINAL STATISTICS =====
Total DPCs/TimerDPCs/ThreadDPCs/Interrupts: 841704
DPC Max:       3920,20 æs (Driver: ndis.sys (10.0.26100.3323 (WinBuild.160101.0800)), Routine: 0xFFFFF80010B18F70, Offset: 0x68F70)
TimerDPC Max:  1066,30 æs (Driver: ntoskrnl.exe (10.0.26100.3775 (WinBuild.160101.0800)), Routine: 0xFFFFF8007D25BA90, Offset: 0x45BA90)
ThreadDPC Max: 0,00 æs (Driver: None (N/A), Routine: 0x0, Offset: 0x0)
Interrupt Max: 398,10 æs (Driver: dxgkrnl.sys (10.0.26100.3775 (WinBuild.160101.0800)), Routine: 0xFFFFF8000ECF3850, Offset: 0x33850)

All DPC/TimerDPC/ThreadDPC/Interrupt Events:
+-----------------+-------------+----------+--------------+--------------------+--------------------+------------------+----------------+--------+
| Driver          | Event Type  | Offset   | Max Duration | Routine            | Base Address       | Version          | Critical Count | Total  |
+-----------------+-------------+----------+--------------+--------------------+--------------------+------------------+----------------+--------+
| ACPI.sys        | DPC         | 0x19E70  | 509,30 æs    | 0xFFFFF8000F4B9E70 | 0xFFFFF8000F4A0000 | 10.0.26100.1     | 0              | 971    |

 

[xrobwx71]

Thanks! Great find!

 

[Digerati]

I'm confused. A tool with the exact same name, designed for the exact same purpose has been around for years - as seen here with the Aug 29, 2016 timestamp. The older one clearly is less informative but at least has an understandable GUI.

Then there's LatencyMon which has been around even longer and serves a similar function.

 

[Maxstar]

That's correct but DPC Latency Checker developed by: TheSyCon is down and only available at SoftPedia. Today I came across this tool by chance when I was searching for the latest DDU-version.

 

[Digerati]

I just think it really odd they use the exact same name. Surely Wagnardsoft developers were aware, or should have been aware of the older program. So I feel the right thing to do should have been to use a different name. "DPC Latency Monitor", perhaps. Oh well.

 

[Maxstar]

I agree that it would have been better to have chosen a different or unique name! However, I am not sure if previous developers are involved with this build? Perhaps someone else knows, there must be a reason using the same name I guess?

 

[Digerati]

Unless copyrighted/trademarked, they can use the same name. It's a bit devious or deceitful, however.

I looked through the list of folks they thanked, and the developer of the original program is not listed. But it does say not all who helped are listed too. So who knows?