User guide

MS-DMT Guide v1.04
Released 05-30-2014
29
The process of determining what process is the offending one requires motoring all processes
with the Windows Task Manager or better yet Process Explorer (procexp.exe) available free
from http://technet.microsoft.com/en-us/sysinternals/bb896653 to associate the timing of CPU
loading or RAM increases with latency spikes and disabling the process to see the results on
latency. When you look at Windows Task Manager and sort the running processes by CPU
(Processor Utilization), the System Idle Process is almost always at the top of the list. What you
may not know is that “process” is really a roll-up of several things. Among other things, included
in that CPU number, is hardware interrupts and DPCs.
After you have disabled a process watch DPC Latency Checker. When excessive latency values
disappear you found the responsible device driver. If there are still exceptional large DPC
latencies try the next process. You will likely see large spikes of short duration when opening
and closing applications and or files and during mouse moment, continual such spikes would be
a negative issue during use of the software. The MS-DMT program itself while running will cause
latency issues.
It has been found that network card drivers and wireless networking especially and various
programs making use of network connections, such as e-mail clients, web browsers and others
are some of the worst case processes regarding latency. Any device driver for plug-in devices are
suspect, to include your sound device. Other negative processes affecting latency are viruses