26.1.2 Despawn Timer and Age Inheritance

Despawn Timer & Age Inheritance (MC 26.1.2)

This document details the despawn lifecycle, tick-to-second conversion math, youngest age inheritance rules, and farm production safeguards in Item Clumps for Minecraft 26.1.2.

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📊 Feature Infobox

Property	Specification
System Name	Youngest Age Despawn Preserver
Vanilla Despawn Threshold	$6,000\text{ ticks}$ ($300\text{ seconds} = 5.0\text{ minutes}$)
Age Inheritance Rule	$\text{age}_{\text{merged}} = \min(\text{age}_A, \text{age}_B)$ (Youngest item wins)
Pickup Delay Rule	$\text{pickupDelay}_{\text{merged}} = \max(\text{pickupDelay}_A, \text{pickupDelay}_B)$ (Longest delay kept)
Target Field	ItemEntity.age and ItemEntity.pickupDelay

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⏳ Tick-to-Second Timing Math

In Minecraft, entity timers run at 20 ticks per second:

$$1\text{ second} = 20\text{ ticks}$$ $$1\text{ minute} = 60\text{ seconds} = 1,200\text{ ticks}$$ $$5\text{ minutes} = 300\text{ seconds} = 6,000\text{ ticks}$$

In vanilla Minecraft, an ItemEntity increments its internal age field by $+1$ every game tick. When $\text{age} \ge 6000$, the item is permanently discarded from the world.

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🛡️ The Youngest Item Safeguard Rule

When two items merge in Item Clumps, the surviving entity executes:

$$\text{age}_{\text{merged}} = \min(\text{age}_{\text{this}}, \text{age}_{\text{other}})$$

Continuous item flow in active mob grinders, automated tree farms, or quarry drill lines repeatedly refreshes the clump age to 0. As long as the farm is actively generating items, no items will ever despawn.

Once the farm stops producing items, the clump sits idle on the ground, and the age timer counts down uninhibited from $0$ to $6000$, safely cleaning up all uncollected items after 5 minutes of inactivity.

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💻 Ground-Truth Java Source Implementation

From ItemEntityMixin.java in Minecraft 26.1.2:

// Complete Merge: larger stack absorbs the smaller stack
if (otherCount < thisCount) {
    thisStack.setCount(thisCount + otherCount);
    this.setItem(thisStack);
    this.pickupDelay = Math.max(this.pickupDelay, ((ItemEntityMixin)(Object)other).pickupDelay);
    this.age = Math.min(this.age, ((ItemEntityMixin)(Object)other).age);
    other.discard();
} else {
    otherStack.setCount(thisCount + otherCount);
    other.setItem(otherStack);
    ((ItemEntityMixin)(Object)other).pickupDelay = Math.max(((ItemEntityMixin)(Object)other).pickupDelay, this.pickupDelay);
    ((ItemEntityMixin)(Object)other).age = Math.min(((ItemEntityMixin)(Object)other).age, this.age);
    this.discard();
}

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🔗 Related Documentation (MC 26.1.2)

• 26.1.2 Mega-Stack Clumping
• 26.1.2 Hopper Integration
• 26.1.2 Architecture & Mixins