Hi,
I believe the 'Performance Monitoring in RTMT' is what you can are loking for...
 
About Performance Monitoring in RTMT:
Cisco Unified Communications Manager updates performance counters (called PerfMon counters). The counters contain simple, useful information about the system and devices on the system, such as number of registered phones, number of active calls, number of available conference bridge resources, and voice messaging port usage.

You can monitor the performance of the components of the system and the components for the application on the system by choosing the counters for any object. The counters for each object display when the folder expands.

For Cisco Unified Communications Manager, the Cisco CallManager object contains most of the Cisco Unified Communications Manager performance counters, and these counters have only one instance. The instance-based counters that belong to the other objects can have zero or more instances. For example, if two phones are registered to Cisco Unified Communications Manager, two instances of each counter that belong to the Cisco phones object exist.

You can log perfmon counters locally on the computer and use the performance log viewer in RTMT to display the perfmon CSV log files that you collected or the Real-time Information Server Data Collection (RISDC) perfmon logs.

RTMT provides alert notifications for troubleshooting performance. It also periodically polls performance counters to display data for that counter. Performance monitoring allows you to perform the following tasks:

¿Monitor performance counters including all the Cisco Unified Communications Manager servers in a cluster (if applicable), TFTP servers, and database servers.

¿Continuously monitor a set of preconfigured objects and receive notification in the form of an e-mail message.

¿Associate counter threshold settings to alert notification. An e-mail or popup message provides notification to the administrator.

¿Save and restore settings, such as counters that get monitored, threshold settings, and alert notifications, for customized troubleshooting tasks.

¿Display up to six perfmon counters in one chart for performance comparisons.
 
Reference:
http://www.cisco.com/en/US/partner/docs/voice_ip_comm/cucm/managed_services/rtmtdeftalrt.html#wp1040430