Profiling Games built with Unreal Engine* (NEW)
Use this recipe to profile a game built with Unreal Engine. See how you can run
Intel® VTune™
within the Unreal Engine environment to profile your game.
Profiler
Often, the most important factor that affects the performance of a game is the frame rate. This is the speed with which the GPU renders game graphics. However, the CPU can also impact game performance in several ways:
- Slow transfer of data to the GPU
- Slow or unnecessary operations
- Poor parallelism
Intel® VTune™
Instrumentation and Tracing Technology (ITT) API built into the Unreal editor. This recipe demonstrates how you can run
Profiler
VTune Profiler
to highlight UE tasks in the editor.
Ingredients
Here are the hardware and software requirements for this performance recipe.
- Application:Unreal Engine 4.25.4. The sample game in this version of Unreal Engine is the Action RPG tutorial.
- Tools:Intel® VTune™version 2022 - Hotspots Analysis (using User-Mode Sampling)Profiler
- Starting with the 2020 release, Intel® VTune™ Amplifier has been renamed toIntel® VTune™.Profiler
- Most recipes in theIntel® VTune™Performance Analysis Cookbook are flexible. You can apply them to different versions ofProfilerIntel® VTune™. In some cases, minor adjustments may be required.Profiler
- Get the latest version ofIntel® VTune™:Profiler
- From theIntel® VTune™product page.Profiler
- Download the latest standalone package from the Intel® oneAPI standalone components page.
- CPU/GPU: 11thGeneration Intel® Core™ i7-1165G7 CPU @ 2.80GHz with Intel® Iris® Xe MAX Graphics
- Operating system: Windows* 11 Enterprise
Build the Game in the Unreal Editor
- Open the game in the Unreal editor.
- Build the game. Make sure to select theDevelopmentBuild Configuration andInclude Debug Filesoptions.
Configure
Intel® VTune™
Profiler and Run Hotspots Analysis
Intel® VTune™
and Run Hotspots Analysis Profiler
- OpenIntel® VTune™and clickProfilerNew Projecton the Welcome screen.
- Specify a project name and a location for your project.
- ClickCreate Project.
- In theConfigure Analysiswindow, set these options:
- In theWHEREpane, selectLocal Host.
- In theApplicationfield of theWHATpane, enter the path to the game executable.
- In theApplication parametersfield, enter-VTune.
- (Optional) If you want to skip profiling the start/loading phase of the game,
- In theWHATpane, open theAdvancedsection.
- Set
- UnderLimit collected data by, set a value in seconds forTime from collection end, sec. This is the duration (in seconds) before the end of the collection for whichIntel® VTune™should retain the results. The data collected earlier than this time gets discarded.Profiler
- In theHOWpane, select theHotspots analysis typeand enable user-mode sampling.
- ClickStartto run the analysis.

If you set the
) is available.
Automatically resume collection after
option in step 5, only the
Start Paused
button (
Review Results
When the data collection stops,
Intel® VTune™
finalizes the results. This process may take a few minutes as
Profiler
Intel® VTune™
finds and resolves debug symbols.
Profiler
Once results have been finalized, the
Summary
tab displays information about:
- Elapsed time
- Top hotspots
- Top Unreal Engine tasks
- Additional insights and guidance

Switch to the
Bottom-up
window to see a list of functions. The default sorting is by descending order of CPU time.
Change the grouping from
Function / Call Stack
to
Task Domain / Task Type / Function / Call Stack
to focus on Unreal Engine tasks which were identified by the
Intel® VTune™
Instrumentation and Tracing Technology API (ITT API).
Profiler


In this example, there is considerable spin time in the Render and Game threads. Also, nearly half of the overall CPU utilization was spent spinning, or waiting for a resource to return.
The CPU utilization histogram (in the
Summary
tab) tells us something important. Although this game was running over 100 threads, for the majority of the run, this game only utilized a single CPU or was mostly idle.
From here, you can try to identify whether the high amount of spin is affecting performance negatively. You can also examine how to make use of more CPU capability. Generally games are not expected to consume the full amount of hardware resources, but there is room on this system for more parallelism.
For additional insights into hotspots, open the
Flame Graph
view to see a graphical representation of call stacks from the top down.
