Using CLR 4.0 NGEN PDB Support

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Both Xperf and Windows Performance Recorder (WPR) can run with Common Language Runtime (CLR) 4.0 Native Image Generator (NGEN) PDB support enabled.

Note  WPR handles CLR symbols directly, so no flags are necessary when configuring and using NGEN support.

When you start a recording in the WPR user interface (UI), NGEN program database files (PDBs) are generated next to the saved recording. These PDBs decode symbols of modules that were created by using NGEN for managed scenarios. For Recording.etl, the NGEN PDBs are in the Recording.etl.NGENPDB folder.

Using NGEN support with WPR

We recommend the following setup before running WPR with NGEN support enabled:

  • (Optional, but recommended) Set the SymCache path environment variable to a local directory

Using NGEN support with Xperf

To use NGEN support with Xperf, do the following:

  1. At an elevated command prompt, type the following:

    set _NT_SYMBOL_PATH=srv*C:\Symbols.NGEN;srv*https://msdl.microsoft.com/download/symbols

  2. Type the following to start the kernel session:

    xperf -on Base -stackwalk Profile -f kernel.etl

  3. Type the following to start the CLR runtime session recording:

    xperf -start ClrSession -on ClrAll:0x98:5 -f clr.etl -buffersize 128 -minbuffers 256 -maxbuffers 512

  4. Run your scenario.

  5. Type the following to start the CLR rundown session:

    xperf -start ClrRundownSession -on ClrAll:0x118:5+a669021c-c450-4609-a035-5af59af4df18:0x118:5 -f clr_DCend.etl -buffersize 128 -minbuffers 256 -maxbuffers 512

  6. Type the following to allow time for CLR rundown to complete by setting the timeout to 15:

    timeout /t 15

  7. Type the following to stop the CLR runtime session, CLR rundown session, and kernel session, and to merge them into a single file:

    xperf -stop ClrSession ClrRundownSession -stop -d recording.etl

Decoding a recording that has CLR 4.0 NGEN PDB support enabled

At an elevated command prompt, type the following:

set _NT_SYMBOL_PATH=srv*C:\Symbols.NGEN;srv*https://msdl.microsoft.com/download/symbols

Transferring a recording that has CLR 4.0 NGEN PDB support enabled

To transfer a recording with CLR 4.0 NGEN PDB support enabled, include the following in the symbol path:

srv*C:\Symbols.NGEN

To transfer the recording to a different computer, make sure that both Recording.etl and the entire folder C:\Symbols.NGEN (along with its subfolders) are transferred.

Symbol Support

symbols