Configure the high resolution timer


+

Search Tips   |   Advanced Search

 

Overview

You can configure agent computers to use a high resolution timer when collecting performance data. The high resolution timer ensures that all measurements are precise to 1 millisecond.

The high resolution timer is used by default on the Linux operating system. You do not need to configure the high resolution timer on the Linux operating system.

For the Windows, AIX, and z/OS operating systems, the high resolution timer is not used by default.

Enabling the high resolution timer can increase processor usage on Windows agent computers. Typically, processor usage increases by 10 to 25 percent, but the increase can vary based on workload.

Enable the high resolution timer on Windows agent computers if you are measuring response times of 15 milliseconds or less, or if you are measuring response times of 150 milliseconds or less and need 1 millisecond precision instead of 15 millisecond precision.

If you enable the high resolution timer on Windows agent computers, monitor the processor usage to determine whether the tradeoff of higher processor usage is acceptable.


Enable the high resolution timer on an agent computer

  1. In the Test Navigator, open the location that represents the agent computer.

  2. Click the General Properties tab.

  3. On the General Properties page, click Add to create a new property for the selected location.

  4. In the New Property window, create a new property entry:

      Property Name RPT_VMARGS
      Operator =
      Property Value -DrptNanoTime

    To set multiple RPT_VMARGS values for a location, place them in the same property entry and separate them with a space. Do not use multiple property entries to set multiple RPT_VMARGS values for a location.

  5. Click OK, and then save the location. The high resolution timer is now enabled for the location.