I am noticing that VariableValueChangedCondition creates about 180B of GC allocation when it runs due to the delegate being removed and readded. (400B when Deep Profile, so I am extrapolating from that.) This can easly be seen when used as the condition in a Restart node near the root of a graph. I…

[image] Behavior Package 1.0.15 Released! Unity Engine We’re excited to announce that Behavior 1.0.15 is now available! This release delivers the long-awaited ObserverAbort support, a set of quality-of-life improvements for faster iteration and d…

[image] MechaWolf99: due to the delegate being removed and readded Is the delegate a lambda? If so, try assigning a named method instead (should be a one-click refactor option in any IDE). Mainly to rule out that the allocation comes from the lambda, since lambdas are going to allocate when t…

No… as you said if it was a lambda it couldn’t be removed… Also according to deep profile it is due to Delegate.Combine() which makes sense to me.

[image] MechaWolf99: I don’t believe there is any way to change the reference to a variable a node uses at runtime. So it should be safe to have a non-serialized bool m_HasRegisteredListener field that is set in RegisterListener() and OnEnd(), and checked in OnStart(). Very good observation, …

[image] MorganHoarauUnity: We will get that patched for the next release. Yay, thank you! :smiley: On a related note I noticed that VariableComparisonCondition also creates some GC when evaluated. I assume from boxing value types. Might be more involved but would be nice if this could also b…

This came up a while ago with the Switch node, but while we can address VariableValueChangedCondition, boxing value type is indeed more involved and would require more work. I like the idea of adding hotpath for the primitive types though. Might have to keep it internal to begin with as this might …

For hot paths, my thinking was in ConditionUtils.Evaluate after checking if both are bloackboard variables, to do checks for the generic primiative types, like if (variable is BlackboardVariable<float> floatVariable) since this would be invisble to end users and would at least get rid of GC for the …

GC allocation of VariableValueChangedCondition

Behavior & Navigation Behavior

MorganHoarauUnity February 2, 2026, 2:11pm 8

The new release contains fixes/improvements to GC allocation for these nodes. Thank you for your contribution!

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GC allocation of VariableValueChangedCondition

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