Capturing and Collecting CPU Processor Power Information

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For installation support see the Installation section of this document.

Perform the following steps to begin capture and collection of CPU processor data:.

  1. Open a command prompt with administrator privileges.

  2. Create a directory \etl and change to that directory. Run WPA from this directory to store all of your trace files in one location.

    C:\>mkdir c:\etl
C:\>cd c:\etl

  3. From the command prompt, start NT Kernel Logger with base and power flags.

    xperf -on power+base

    In this case, we are setting two options or flags. The first option, power, sets a kernel flag that causes WPA to collect events related with CPU power and frequency modulation. The second flag, base, is a kernel group that includes the flags shown in the following table.

    Option Usage
    PROC_THREAD
    		 Lists process and thread create/delete events
    LOADER
    		 Shows kernel and user-mode load and unload events
    DISK_IO
    		 Tracks disk activity for the session
    HARD_FAULTS
    		 Lists hard page faults
    PROFILE
    		 Creates a CPU sample profile
    MEMINFO
    		 Displays Memory list information

  4. Run an application that causes the CPU to work. In this case, we will start a DVD and turn it off immediately.

  5. Stop the trace. Use the -d flag with the xperf command that causes WPA to stop collecting events. powerTrace.etl names the trace file where the captured events are collated and stored.

    xperf -d powerTrace.etl

  6. Analyze the trace.

    xperfview powerTrace

The Reviewing Trace Event Information topic explains some of the information that has been collected in the trace file powerTrace.etl.