Quick Start - Enabling Data Capture on Process Launch

Enabling data capture on process launch guarantees that there will be no loss of allocation information or history. Take the following steps to enable data capture on process launch:

1. If Windows Sidebar is running, open Windows Task Manager and end any sidebar.exe processes.

2. Open an elevated command prompt. It is recommended to identify a single directory from which WPA is run and change to that directory.

3. From the command prompt enter the following:

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   C:\etl> xperf -on Base -BufferSize 1024  -MinBuffers 10 -MaxBuffers 16
   
   

   By default, WPA will automatically turn on the "NT Kernel Logger" which collects kernel events. The kernel group "Base" will trigger the collection of events from the following event providers:

   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	Captures memory list information

    

4. Next, enter the following on a single line:

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   C:\etl> xperf -start HeapSession -heap -PidNewProcess "C:\Program Files\Windows Sidebar\sidebar.exe" -BufferSize 1024 -MinBuffers 128 -MaxBuffers 128 -stackwalk HeapAlloc+HeapRealloc
   
   

   The following table explains each of the commands, parameters and options employed.

   Option, command or parameter	Usage
   xperf	Runs the main xperf program with the specified parameters and options.
   -start HeapSession	Initializes a tracing session or logger session. In this case the session is named "HeapSession".
   -heap	Identifies HeapSession as a heap trace.
   -PidNewProcess	Initializes a process. In this case the Windows Sidebar will be started.
   -BufferSize	Sets the buffer size where the event data will be stored. 1024K is an optimum buffer size. By default WPA will use 64K.
   -MinBuffers	Sets the minimum number of buffers for event data storage. MinBuffers should be equal to MaxBuffers in order to guarantee consistency between traces.
   -MaxBuffers	MaxBuffers should be allocated conservatively because buffers are allocated from non-paged memory, a finite system resource.
   -stackwalk	Initializes the stackwalk facility to collect allocation and de-allocation information and associate that information with specific threads.
   HeapAlloc+HeapRealloc	Identifies specific heap events to be captured and presented by the stackwalk facility.

    

5. At this point the sidebar will open on the desktop.

6. In the command window, enter the following on a single line:

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   C:\etl> xperf -stop -stop HeapSession -d heapTrace.etl
   
   

   The following table explains each of the commands, parameters and options:

   Option, Command or Parameter	Usage
   xperf	Runs the main xperf program with the specified parameters and options.
   -stop HeapSession	Indicates a session will be ended. In this case, end the session "HeapSession".
   -d heapTrace.etl	Merges traces produced in the session into the trace file "heapTrace.etl".

    

   For more information on WPA start and stop options, use the command line query:

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   C:\etl> xperf -help start
   C:\etl> xperf -help stop
   
   

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Build date: 2/12/2012