Profile Unreal Engine Application

Technically, you can profile an Unreal Engine application as any other native application using the Standalone application type. Nevertheless, it is more convenient to use the Unreal Engine application type for this purpose as it predefines the necessary profiling settings.

Prerequisites

You have PDB files of your Unreal Engine application. The path to the PDB files is specified in the _NT_SYMBOL_PATH environment variable. You can also specify the path when configuring a profiling session.

Run dotTrace as a standalone application. The dotTrace Home window will open.
If the native application is already running, in the Running Process list, select Show native processes and then select the native process you want to profile. Ignore steps 2 and 3.
Add a run configuration – the configuration that tells dotTrace how to run the profiled application:
1. Under Choose what you want to profile, New Process Run, click Add run configuration.
2. In the New Run Configuration wizard, choose Unreal Engine and click Next.
3. Specify application options:
  - Path to the application executable.
  - Command-line Arguments for the executable (if required).
  - A full path to the application Working directory (by default, it is the same directory where the executable is located).
  - Set environment variables lets you run the profiled application with specific environment variables. Each variable must be specified on a new line.
4. Click Save.
Make sure the created run configuration is selected in the New Process Run list.
Under Choose how you want to profile it, specify profiling options:
- In Profiling Type, select Timeline. Other profiling types are not supported – there will be no native call stack data in the snapshot.
- Optionally, if your application creates a number of processes and you want to profile only specific ones, configure process filters.
- If you want to collect memory allocation data (what functions allocate memory), make sure Collect native allocations is selected.
- Configure PDB files location:
  By default, dotTrace expects to find the application PDB files in the locations specified in the _NT_SYMBOL_PATH environment variable. You can specify alternative file locations under Edit Symbol File Locations: these could be local or remote locations. If you want dotTrace to get the PDB files from remote servers, you should also select the Download symbol files checkbox. PDB files download starts right after you get a snapshot and can take a significant amount of time depending on the file size.
- If required, specify other profiling options.
If you want dotTrace to start collecting profiling data right after you start the session, under Run profiling, select Collect profiling data from start.
Click Start. This will start the profiling session.
Go through a particular workflow in your application (if you want to evaluate its performance) or reproduce a particular performance issue. Collect snapshots using the Get Snapshot button in the profiling controller window. Learn more about how to control the profiling session
After you collect the data, either close the profiled application or detach the profiler using the Detach button in the controller window.
Analyze the collected snapshots in the dotTrace Viewer.

Last modified: 26 May 2024