The Cisco CallManager generally checks the timer threads once every second. Cisco CallManager adds 1 second to the current operating system time and stores that value away as “expected time.†Then, Cisco CallManager sleeps for 1 second. After Cisco CallManager awakes, it checks the new operating system time and subtracts the expected time. If the difference between these two times is more than 1 second, this warning statement appears in the Cisco CallManager trace:
CMProcMon::star_sdlVerification - Test Timer exceeded minimum timer latency
threshold of 1000 milliseconds, Actual latency: 1630 millisecondsActual latency in this statement shows that the internal Cisco CallManager SDL timer thread runs slow. Here, the difference between the Cisco CallManager expected time and the actual operating system time is 1.63 seconds.
If this difference exceeds 16 seconds, the Cisco CallManager shuts down and provides the shutdown reason code of 4.
The most likely cause of an SDL timer thread shutdown is a lack of CPU time for Cisco CallManager. Another application, such as VirusScan or STI Backup, has used most of the CPU resources for at least 16 seconds. Perfmon logs are vital to determine the root cause of this type of shutdown.
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