The Cisco CallManager service can crash because the service does not
have enough resources such as CPU or memory to function. Generally, the CPU
utilization in the server is 100 percent during this time. This document
discusses the problems that cause high CPU utilization and their
Note: CPU spikes on a Cisco CallManager server can be normal depending on
what service/application runs at the time. But, sustained CPU spikes are not
good and can cause the CallManager service to terminate or issues like delayed
dialtone, and so forth.
There are no specific requirements for this document.
The information in this document is based on Cisco CallManager 3.x and
The information in this document was created from the devices in a
specific lab environment. All of the devices used in this document started with
a cleared (default) configuration. If your network is live, make sure that you
understand the potential impact of any command.
Technical Tips Conventions for more information on document
The InsertCDR.exe application spikes and then results in high CPU
utilization in the Cisco CallManager server.
This issue arises when the Cisco Call Detail Record (CDR) Insert
service is activated and the CDR Enabled flag is not set to
Complete these steps in order to solve this issue.
Go to the Cisco CallManager Administration
Choose Service Parameter and select Cisco
Change the CDR Enabled Flag value to True and
restart the Cisco CallManager service.
The sql.exe application consumes high CPU which reduces performance of
the Cisco CallManager Publisher server.
This issue can be caused by any third party billing application
installed in the Cisco CallManager Publisher server. In order to resolve this,
stop the application and restart the Cisco CallManager server.
This problem might arise when you use a short duration WAV file that
loops for Music on Hold (MoH). The CPU utilization is caused by the constant
looping that needs to take place when you play a short duration WAV file.
In order to resolve this issue, use a longer duration WAV file that
loops less often. This decreases the CPU utilization.
In the Cisco CallManager 4.x cluster, aupair.exe causes high CPU
utilization on the Cisco CallManager subscriber server. The Cisco Database
Layer Monitor service (aupair.exe) monitors aspects of the database layer as
well as CDRs. The database layer comprises a set of dynamic link libraries
(DLLs) that provides a common access point for applications that need to access
the database to add, retrieve, and change data.
Complete these steps in order to resolve this issue:
Restart the CDR Insert service on the
Restart the Database Layer Monitor service and the RIS Collector
service on both the publisher and subscriber.
Use DBLHelper to reestablish a broken Cisco CallManager Cluster SQL
DBLHelper to Reestablish a Broken Cisco CallManager Cluster SQL
Subscription for more information about DBLHelper.
Sometimes, the performance monitoring service such as Realtime
Information Server Data Collection (RISDC) can result in a CPU spike.
Complete these steps in order to restart the RISDC service and resolve
Go to the Cisco CallManager Administration page and choose
Application > Cisco CallManager
Go to Tools > Control Center
and select the appropriate CallManager server from the list of servers.
Select the Cisco RIS Data Collector service and
Sometimes the Cisco CallManager response becomes very slow when a user
answers calls, transfers calls, puts a call on hold, and even pulls a dial tone
to the IP phone. When this happens, the tcdsrv.exe service causes high CPU
which is responsible for telephony call dispatching.
Tcdsrv.exe is a service used for Telephony call dispatching and made
for use with Attendant Console. If the CallManager does not use Attendant
Console, stop the Telephony call dispatching service from the Control
Center in the Cisco CallManager Serviceability