Guardian Subsystem

Base:

UTickableWorldSubsystem

Type:

UNGuardianSubsystem

Header File:

NexusGuardian/Public/NGuardianSubsystem.h

A developer-focused UTickableWorldSubsystem that monitors UObject count growth against a baseline and triggers a staged warning → snapshot → compare ladder once configured thresholds are crossed. The subsystem is only created in build configurations selected by Build Availability, so it can ship in development builds and be entirely absent from Shipping.

For a live readout of the same counters, use the Developer Overlay.

Snapshots

Over the course of a game's development, there comes a point where you start to wonder, do I have a leak? While there are many great tools included with the Unreal Engine — we are looking at you Insights! Sometimes you just want to go old-school and printf everything to a log. We have you covered!

tip

While the UNGuardianSubsystem provides an automatic monitoring solution, you can manually use N.Developer.CacheSnapshot and N.Developer.CompareSnapshot console commands to create your own diffs! Check out the other console commands!

Setting A Baseline

The automated system requires a baseline point to be effective in its calculations. Mainly because there is going to be a period where you are creating numerous UObjects, and you don't want the system to consider those objects in its calculation. So when you are ready for it to start watching, call the SetBaseline() command.

Blueprint

C++

Set Delayed Baseline

FTimerHandle SetBaselineTimerHandle;
GetWorld()->GetTimerManager().SetTimer(SetBaselineTimerHandle, UNGuardianSubsystem::Get(GetWorld()), &UNGuardianSubsystem::SetBaseline,1.0f, false);

The subsystem is Conditional-tickable and only consumes tick budget after the baseline has been captured.

The Threshold Ladder

Once the baseline is set, every tick samples the total UObject count and compares it against three thresholds resolved from Project Settings (baseline + setting):

Threshold	Action when crossed	Latched flag
Warning	Emits a log warning.	HasPassedWarningThreshold()
Snapshot	Captures an FNObjectSnapshot of every live UObject. Held in memory; written to Saved/Logs/NEXUS_Snapshot_* if Save Capture is enabled.	HasPassedSnapshotThreshold()
Compare	Captures a second snapshot and diffs it against the first; writes Saved/Logs/NEXUS_Compare_* if Save Capture is enabled.	HasPassedCompareThreshold()

Each action fires exactly once — the latched flag is checked before the action runs, so the subsystem will not re-warn or re-snapshot until the world (and its subsystem) is recreated.

Reading State

The following accessors are intended for HUD overlays, automated tests, or any tooling that wants to observe the subsystem without driving it:

Method	Returns
GetLastObjectCount()	The most recent UObject count sampled in tick.
GetBaseObjectCount()	The count latched by SetBaseline(). Zero before baseline is set.
GetObjectCountWarningThreshold()	The resolved warning threshold (baseline + setting).
GetObjectCountSnapshotThreshold()	The resolved snapshot threshold.
GetObjectCountCompareThreshold()	The resolved compare threshold.
HasPassedWarningThreshold()	true once the warning fired.
HasPassedSnapshotThreshold()	true once the snapshot was captured.
HasPassedCompareThreshold()	true once the compare ran.