Unreal Insights Reference

Animation

Animation Insights(GameplayInsights/RewindDebugger) plugin.

Runtime\Engine\Private\Animation\AnimTrace.cpp

AssetLoadTime

Named CPU timers for UObject::Serialize. Also toggles on Blueprint names. Requires CPU channel and -statnamedevents.

All platforms.

Runtime\Core\Private\Serialization\LoadTimeTrace.cpp Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp

Asset Metadata

Asset Names and Class Names as metadata for memory allocations. Requires Metadata channel. Used by the MemAlloc channel.

• Win64

• XB1/XSX

• PS4/PS5

• Switch

• Linux

Engine\Source\Runtime\Core\Public\ProfilingDebugging\MetadataTrace.h

BookMark

Low frequency markers signifying important transitions, providing a quick overview for users. Such as level loading or engine boot phases.

Runtime\Core\Private\ProfilingDebugging\MiscTrace.cpp

Callstack

Callstack descriptions. Allows allocations to be associated with callstacks.

• Win64

• XBox

• PS4/PS5

• Switch

Runtime\Core\Private\ProfilingDebugging\CallstackTrace.cpp

Concert

Concert plugin.

Plugins\Developer\Concert\ConcertMain\Source\ConcertTransport\Private\ConcertLogGlobal.cpp

ContextSwitch

Trace context switch events. On Windows, game/editor runtime should be "run as administrator".

• Win64

• XBox

• PS4/PS5

Runtime\Core\Private\ProfilingDebugging\PlatformEvents.cpp

Cook

Displays named CPU timers specific to cooking. This requires the CPU channel. It will add the "CookByTheBook" and "SaveCookedPackage" cpu timing events (with metadata).

Editor\UnrealEd\Private\Cooker\CookProfiling.h/.cpp

Counter

Generic counters. Allows tracing of values (float, integer) over time. Counters Trace API. It also enables the CSV Profiler Trace.

Runtime\Core\Private\ProfilingDebugging\CountersTrace.cpp

CPU

Named cpu timers.

Runtime\Core\Private\ProfilingDebugging\CpuProfilerTrace.cpp

File

File I/O trace channel (Open, ReOpen, Read, Write, Close events).

• Win64

• Mac,

• XBox

• PS4.

Runtime\Core\Private\ProfilingDebugging\PlatformFileTrace.cpp

Frame

Game and Rendering frames.

Runtime\Core\Private\ProfilingDebugging\MiscTrace.cpp

GPU

Named gpu timers. Based on GpuProfiler data.

Runtime\RHI\Private\GpuProfilerTrace.cpp

LevelSnapshots

Level Snapshots plugin.

Plugins\VirtualProduction\LevelSnapshots\Source\LevelSnapshots\Private\LevelSnapshotsLog.cpp

LoadTime

Asset Loading Insights trace channel. Package load times (specific trace events) + named cpu timers specific to package loading. Requires "cpu" channel. Also adds the "LoadPackageInternal" cpu timing events (with metadata). See usage of SCOPED_LOADTIMER and SCOPED_CUSTOM_LOADTIMER macros.

Runtime\Core\Public\ProfilingDebugging\LoadTimeTracker.h Runtime\Core\Private\Serialization\LoadTimeTrace.cpp

Log

Logs Messages.

Runtime\Core\Private\Logging\LogTrace.cpp

MemAlloc

Memory allocations. Uses Module and Callstack.

• Win64

• XBox

• PS4/PS5

• Switch

Runtime\Core\Private\ProfilingDebugging\MemoryTrace.cpp

Memory

Includes all alloc events, callstacks, and tags. This is equivalent to -trace=memalloc,callstack,memtag.

Runtime\Core\Private\ProfilingDebugging\MemoryTrace.cpp

Memory_Light

Includes all alloc events and tags. This is equivalent to -trace=memalloc,memtag.

Runtime\Core\Private\ProfilingDebugging\MemoryTrace.cpp

MemTag

Memory tag statistics. Traces snapshots of memory usage per tag at regular rate. Relies on LLM subsystem for tracing. Implies "-llm". Available after Init().

Runtime\Core\Private\HAL\LowLevelMemTracker.cpp

Messaging

UDP Messaging plugin.

Plugins\Messaging\UdpMessaging\Source\UdpMessaging\Private\UdpMessagingTracing.cpp

Metadata

Support for generic metadata scopes.

All platforms.

Engine\Source\Runtime\Core\Public\ProfilingDebugging\MetadataTrace.h

Module

Module loading information

• Win64

• XBox

• PS4/PS5

• Switch

Runtime\Core\Private\ProfilingDebugging\ModuleDiagnostics.cpp

Net

Networking trace channel. Requires -NetTrace=1 (it enables the "Frame" channel)

Runtime\Net\Core\Private\Net\Core\Trace\Reporters\NetTraceReporter.cpp

NetworkPrediction

Network Prediction Insights plugin.

Plugins\Runtime\NetworkPrediction\Source\NetworkPrediction\Private\NetworkPredictionTrace.cpp

Niagara

Niagara plugin.

Plugins\FX\Niagara\Source\Niagara\Private\NiagaraTrace.cpp

Object

GameplayInsights/RewindDebugger plugin. UObject classes, worlds, instances and events.

Runtime\Engine\Private\ObjectTrace.cpp

ObjectProperties

GameplayInsights/RewindDebugger plugin.

Plugins\Animation\GameplayInsights\Source\GameplayInsights\Private\ObjectPropertyTrace.cpp

Physics

Chaos Visual Debugger.

Runtime\Experimental\Chaos\Private\ChaosVisualDebugger\ChaosVisualDebuggerTrace.cpp

PoseSearch

PoseSearch plugin.

Plugins\Experimental\Animation\PoseSearch\Source\Runtime\Private\Trace\PoseSearchTraceLogger.cpp

RDG

RDG Insights plugin.

Runtime\RenderCore\Private\RenderGraphTrace.cpp

Regions

Long-duration timing events.

All platforms.

Runtime\Core\Public\ProfilingDebugging\MiscTrace.h

RenderCommands

Cpu/Gpu named timers for commands executed on the rendering thread.

Runtime\RenderCore\Private\RenderingThread.cpp

RHICommands

Cpu/Gpu named timers for RHI commands.

Runtime\RHI\Private\RHICommandList.cpp

SaveTime

Named CPU timers specific to package saving. This requires the CPU channel. Adds cpu timers named with UPackage_Save_ prefix. See the usage of the SCOPED_SAVETIMER macro for additional details.

Runtime\CoreUObject\Private\UObject\SavePackage\SavePackageUtilities.h / .cpp

Screenshot

Captures screenshots triggered with Trace.Screenshot console command or using the TRACE_SCREENSHOT() API.

All platforms.

Runtime\Core\Public\ProfilingDebugging\MiscTrace.h

Slate

Slate Insights plugin.

Runtime\SlateCore\Private\Trace\SlateTrace.cpp

Stats

Stats counters. Based on the Stats system.

Runtime\Core\Private\Stats\StatsTrace.cpp

Task

Task Graph trace channel.

Runtime\Core\Private\Async\TaskTrace.cpp

TraceSourceFilters

Trace Source Filtering plugin.

Plugins\Developer\TraceSourceFiltering\Source\SourceFilteringTrace\Private\SourceFilterTrace.cpp

VisualLogger

Visual Logger starts recording to file.

Runtime\Engine\Private\VisualLogger\VisualLoggerTraceDevice.cpp

Audio

AudioInsights logic data (asset load/unload/start/stop, etc.)

Engine/Source/Runtime/AudioMixerCore/Private/AudioMixer.cpp

AudioMixer

AudioInsights parameter data (amplitude, pitch, etc.)

Engine/Source/Runtime/AudioMixerCore/Private/AudioMixer.cpp

ChaosLocks

Chaos physics read/write lock acquisition events (begin, acquired, end) with cycle timestamps. Useful for diagnosing lock contention in the physics solver.

Engine/Source/Runtime/Experimental/Chaos/Private/ChaosInsights/ChaosInsights.cpp

Http

HTTP dispatcher and request lifecycle events: dispatcher/category creation, request start (URL, priority), chunk range additions, and request completion (status code, content length).

Engine/Source/Runtime/Core/Private/ProfilingDebugging/HttpTrace.cpp

IoStore

I/O dispatcher requests, backend operations, and chunk loading.

Engine/Source/Runtime/Core/Private/ProfilingDebugging/IoStoreTrace.cpp

Mass

Mass Entity system archetypes, queries, and chunk execution.

Engine/Source/Runtime/MassEntity/Private/MassEntityTrace.cpp

PhysicsSync

Physics sync insights.

Engine/Source/Runtime/Core/Private/PhysicsSyncInsights.cpp

RaceDetector

Race condition detection for thread safety analysis. Part of the sanitizer infrastructure for detecting data races and concurrent memory access violations.

Engine/Source/Runtime/Core/Private/Sanitizer/RaceDetector.cpp

RenderTrace

RHI command lists, render-graph (RDG) passes, translate jobs, GPU payload submissions and sync points/fences; consumed by the RenderTraceInsights plugin.

Engine/Source/Runtime/RHI/Private/RenderTracing.cpp

Spatial

Named spatial point data (position, velocity, direction) sampled over time. Allows tracking the spatial state of arbitrary points for debugging movement or physics.

Engine/Source/Runtime/Core/Private/ProfilingDebugging/SpatialTrace.cpp

StackSampling

Trace stack sampling events. On Windows, game/editor runtime should be run as administrator.

Engine/Source/Runtime/Core/Private/ProfilingDebugging/PlatformEvents.cpp

ThreadIdleScope

Thread idle time tracking. Marks periods when threads are idle or waiting by adding CPU profiler events for them.

Engine/Source/Runtime/Core/Private/Stats/ThreadIdleStats.cpp

WorldStreaming

World streaming data (experimental — names/events subject to change).

Engine/Source/Runtime/Engine/Private/ProfilingDebugging/WorldStreamingTrace.cpp

WorldStreamingPriority

Per-frame priority sort over all streaming cells (experimental).

Engine/Source/Runtime/Engine/Private/ProfilingDebugging/WorldStreamingTrace.cpp

WorldStreamingDependencies

World streaming dependency data (experimental).

Engine/Source/Runtime/Engine/Private/ProfilingDebugging/WorldStreamingTrace.cpp

CurveEditor

Curve Editor–specific CPU profiling events. Tracks performance of curve editing operations including key modifications, curve snapshots, diff calculations, and selection operations.

Engine/Source/Editor/CurveEditor/Private/CurveEditorTrace.cpp

DDCRemoteExec

DDC remote build executor: per-action state transitions, worker registration, queue submission, completion polling.

Engine/Source/Editor/UnrealEd/Private/DerivedDataBuildRemoteExecutor.cpp

DDCRemoteExecPayload

DDC remote build executor: action and worker descriptor bytes, plus result main-object bytes.

Engine/Source/Editor/UnrealEd/Private/DerivedDataBuildRemoteExecutor.cpp

CameraSystem

Per-frame Gameplay Cameras evaluation data (pose, FOV, evaluator/blend hierarchy).

Engine/Plugins/Cameras/GameplayCameras/Source/GameplayCameras/Private/Debug/CameraSystemTrace.cpp

Chooser

Chooser evaluation tracing.

Engine/Plugins/Chooser/Source/Chooser/Private/ChooserTrace.cpp

EpicRtc

EpicRTC WebRTC streaming events.

Engine/Plugins/Media/PixelStreaming2/Source/PixelStreaming2RTC/Private/EpicRtcTrace.cpp

EpicRtcProfiling

EpicRTC memory/profiling instrumentation.

Engine/Plugins/Media/PixelStreaming2/Source/PixelStreaming2RTC/Internal/EpicRtcCallstack.h

FieldNotification

Field notification events for ViewModel/MVVM bindings.

Engine/Plugins/Developer/FieldNotificationTrace/Source/FieldNotificationTrace/Private/Trace/FieldNotificationTrace.cpp

Modifier

Actor modifier execution profiling for Virtual Production.

Engine/Plugins/VirtualProduction/ActorModifierCore/Source/ActorModifierCore/Private/Modifiers/Profiler/ActorModifierCoreProfiler.cpp

PixelStreaming

PixelStreaming (v1) remote rendering/streaming: video encoding/decoding, audio processing, streaming state, and performance metrics.

Engine/Plugins/Media/PixelStreaming/Source/PixelStreaming/Private/PixelStreamingTrace.cpp

PixelStreaming2

PixelStreaming2: video/audio streaming, video source/sink management, thread operations, capture pipeline, and performance metrics.

Engine/Plugins/Media/PixelStreaming2/Source/PixelStreaming2/Private/PixelStreaming2Trace.cpp

RigVM

RigVM execution and variable state for rewind debugging, including literal/work/debug/external memory, draw interface, instruction visit info, and profiling.

Engine/Plugins/Runtime/RigVM/Source/RigVM/Private/RigVMTrace.cpp

StateTreeDebug

StateTree state machine execution debugging: world timestamps, asset IDs, instance events, phase transitions, log messages, state changes, task/evaluator/transition/condition execution.

Engine/Plugins/Runtime/StateTree/Source/StateTreeModule/Private/Debugger/StateTreeTrace.cpp

TakeRecorder

Take recording operations for virtual production: recording sessions, playback, and take management.

Engine/Plugins/VirtualProduction/Takes/Source/TakeRecorder/Private/TakeRecorderTracing.cpp

UAF

Universal Animation Framework trace data for rewind debugging.

Engine/Plugins/Experimental/UAF/UAF/Source/UAF/Private/RewindDebugger/UAFTrace.cpp

Gameplay Insights / Rewind Debugger

Toggles the Object channel when Play in Editor (PIE) is started, and toggles ObjectProperties, Animation, and Frame when a recording is started.

TraceSourceFiltering

When the plugin is enabled, the TraceSourceFilters channel is toggled on.

NetworkPrediction

When the plugin is enabled, the NetworkPrediction channel is toggled on.

PoseSearch

When the plugin is enabled, the Pose Search channel is toggled on.

Visual Logger

When recording the Visual Logger channel is toggled on.

-NetTrace=1

When enabled from the command line, the Net and Frame channels are toggled on.

UE_TRACE_ENABLED

On

Engine/Source/Runtime/TraceLog/Public/Trace/Config.h

Master control for the entire system.

UE_TASK_TRACE_ENABLED

On

Engine/Source/Runtime/Core/Public/Async/TaskTrace.h

Controls tracing of Task Graph events. -trace=default,task

LOGTRACE_ENABLED

On

Engine/Source/Runtime/Core/Public/Logging/LogTrace.h

Controls whether log messages are reported to Unreal Insights. -trace=log

MISCTRACE_ENABLED

On

Engine/Source/Runtime/Core/Public/ProfilingDebugging/MiscTrace.h

Controls tracing for bookmarks, frames, threads, and thread groups. -trace=bookmark,frame

CPUPROFILERTRACE_ENABLED

On

Engine/Source/Runtime/Core/Public/ProfilingDebugging/CpuProfilerTrace.h

Controls tracing for CPU timers and timing events. -trace=cpu

LOADTIMEPROFILERTRACE_ENABLED

On

Engine/Source/Runtime/CoreUObject/Public/Serialization/LoadTimeTrace.h

Controls tracing for events related to load assets. -trace=loadtime

STATSTRACE_ENABLED

On

Engine/Source/Runtime/Core/Public/Stats/StatsTrace.h

Controls tracing for stats counters. -trace=stats

PLATFORMFILETRACE_ENABLED

On

Engine/Source/Runtime/Core/Public/ProfilingDebugging/PlatformFileTrace.h

Controls tracing for file activity, such as opening, closing, reading, and writing files. -trace=file

PLATFORM_SUPPORTS_PLATFORM_EVENTS

On

Engine/Source/Runtime/Core/Private/ProfilingDebugging/PlatformEvents.h

On for platforms with support for platform events (context switch events). -trace=ContextSwitch

GPUPROFILERTRACE_ENABLED

On

Engine/Source/Runtime/RHI/Public/GpuProfilerTrace.h

Controls GPU timers and timing events. -trace=gpu

UE_NET_TRACE_ENABLED

On

Engine/Source/Runtime/Net/Core/Public/Net/Core/Trace/NetTrace.h Engine/Source/Runtime/Net/Core/Public/Net/Core/Trace/Config.h

Controls tracing of network packet content. -trace=net

UE_MEMORY_TAGS_TRACE_ENABLED

On

Engine/Source/Runtime/Core/Public/ProfilingDebugging/TagTrace.h

Enables tracing of tag scopes. If disabled traced allocation will not have an associated tag. -trace=memtag

UE_CALLSTACK_TRACE_ENABLED

On

Engine/Source/Runtime/Core/Public/ProfilingDebugging/CallstackTrace.h

Enables tracing of callstacks. If disabled traced allocations will not contain callstacks. -trace=callstack

-trace -trace=<channel1>

Provides you the capability to manage how much trace data to generate by categorizing events into named groups.

Trace data for enabled channels is cached in the "Always on" buffers.

-tracehost=<ip>

Sends a trace to the specified IP address. Will default to a local host address.

-tracefile, -tracefile =<filename>

Performs a "WriteTo" file trace control command. This will run the trace default command.

-tracefiletrunc

-tracetailmb= N

N specifies the size of the trace tail buffer in MiB. The default size of the trace tail buffer is 4 MiB.

-notraceserver

If specified, the game or editor will not start the local trace server.

-statnamedevents

logs trace data for stat named events. Can be enabled by GCycleStatsShouldEmitNamedEvents = 1; or from calling "Stat NamedEvents" as a console command.

-verbosenamedevents

logs trace data for verbose named events. Can be enabled by GCycleStatsShouldEmitVerboseNamedEvents = 1; or from calling "Stat VerboseNamedEvents" as a console command. An example of a verbose cycle status: "CPU Stall - [...]", "Other TaskGraph Stalls", "FQueuedThread::Run.WaitForWork".

Trace.Send <Host> [ChannelSet]

Starts tracing to a trace store.<Host> is the IP address or hostname of the trace store. [ChannelSet] is an optional comma-separated list of trace channels/presets to be enabled.

Trace.SnapshotSend <Host> <Port>

Send a snapshot of the current in-memory trace buffer to a trace store.

Trace.File [<File>] [ChannelSet]

Begins tracing events to a file. If a file path is not specified, then the default path directory for the utrace file is: YourProject/Saved/Profiling. If a name is not specified, the name of the utrace file is generated automatically based on the current timestamp. Supports Late Connect.

Use Examples:

• trace.file [ChannelSet]paths to YourProject}/Saved/Profiling/ the *.utrace. Filename is generated automatically.

• trace.file MyFile.utrace [ChannelSet] paths to YourProject/Saved/Profiling/MyFile.utrace.

• trace.file C:/Path/ [ChannelSet] is an absolute path, the filename is generated automatically.

• trace.file Path/ [ChannelSet] is a relative path to YourProject/Saved/Profiling/, the filename is generated automatically.

Trace.Start[ChannelSet]

Keeps the default enabled channels.

Trace.Stop

Stops tracing profiling events.

Trace.Enable[ChannelSet]

Enables a set of channels.

Trace.Disable[ChannelSet]

Disables a set of channels. If no channel set is specified, all channels will be disabled.

Trace.Pause

Pauses all trace channels currently sending events.

Trace.Resume

Resumes tracing that was previously paused (re-enables the pushed channels).

Trace.Status

Prints the trace status to the console.

-OpenTraceId

-OpenTraceId=id

Forces Unreal Insights to start analyzing the specified ID in "Viewer mode"

-OpenTraceFile

-OpenTraceFile=file.utrace

Forces Unreal Insights to start analyzing the specified file in "Viewer mode"

-Store

-Store=<ip>:port

Connects Browser with specified trace store

-TraceAutoStart

-TraceAutoStart=[0|1]

Start tracing to the local trace server automatically at start if Unreal Insights is running or wait to initiate via console command. Default is on.

-NoTraceThreading

-NoTraceThreading

Disable the trace worker thread.

Left mouse click

Select a frame

Right mouse click

Open context menu

Left/right mouse drag

Horizontal zoom

Mouse wheel

Horizontal zoom

Shift + mouse wheel

Vertical zoom

Left/right mouse drag

Horizontal or vertical pan

Ctrl + left/right mouse drag

Horizontal pan

Shift + left/right mouse drag

Vertical pan

Mouse wheel

Zoom

Ctrl + mouse wheel

Horizontal scroll

Shift + mouse wheel

Vertical scroll

Right mouse click

Open context menu

Left mouse click on Timing Event

Select the timing event

Left mouse click on empty space

Clear selection

Ctrl + double left mouse click

Select time range of selected timing event

Left/right mouse drag over Time Ruler

Select time region

Ctrl+F

Toggles the Quick Find menu.

F

Frame the last selection and then alternate between framing the time range or the timing event

G

Toggle Graph track visibility, showing Game and Rendering frames, including a placeholder for Counter series

Y

Toggle GPU Timing track visibility

U

Toggle CPU Timing track visibility

I

Toggle I/O Overview and Activity track visibility

O

Toggle visibility of background events for file activities in the I/O Activity track

L

Toggle Asset Loading track visibility

C

Switch between normal and compact mode, affecting how timing events are visualized

V

Auto hide empty timelines

X

Chooses the next event depth limit: Single Lane, 4 Lanes, Unlimited.

B

Toggle visibility of bookmarks

M

Toggle visibility of time markers (all trace logs instead of just bookmarks)

**-/+

Zoom

Ctrl + left/right/Up/Down arrows

Horizontal and vertical pan

Left/right/Up/Down arrows

Select timing event that is its previous or next sibling/parent/largest child

Enter

Select time range of selected timing event

Left mouse click on packet

Selects the respective packet

Shift + left mouse click on different packet

Selects a range of packets

Ctrl + A

Select all packets

Left/right arrows

Selects previous/next package

Shift + left/right arrows

Extends selection (multiple packages) toward Left/right side

Ctrl + shift + left/right arrows

Shrink selection (multiple packages) from Left/right side

Double click an Event

Highlights all packets containing the event in the Packet Content view while masking out all other events