ModernUO/Projects/UOContent/Items/Misc/EffectItem.cs
Kamron Batman ee2cd1d18d
feat: Adds new decay system and SkipSerialization (#2311)
## Summary

- Replaces scan-based decay checking during world saves with an event-driven timer wheel scheduler
- Removes virtual property checks from serialization hot path, achieving 6-8x faster world saves

## Changes

### DecayScheduler (new):
- Timer wheel with 12 HashSet buckets (5-min intervals) + PriorityQueue for active processing
- O(1) register/unregister vs O(n) scan of all items
- Auto start/stop when items exist/empty
- Configurable tick interval with jitter to prevent system synchronization

### Item.cs:
- Added ScheduledDecayTime computed property
- Added UpdateDecayRegistration() called from SetLastMoved(), property setters, AddItem()/RemoveItem()
- Hooks in Visible, Movable, Spawner setters and Delete()

### World.cs:
- Removed _decayQueue, EnqueueForDecay(), ProcessDecay()
- ItemPersistence.Serialize() now tight loop without virtual calls

## Performance

| Metric        | Before     | After     | Improvement |
|---------------|------------|-----------|-------------|
| Items (230K)  | 245K ticks | 34K ticks | 8x faster   |
| Mobiles (43K) | 56K ticks  | 6K ticks  | 9x faster   |
| Total         | 302K ticks | 40K ticks | 7.5x faster |

## Configuration

decay.maxItemsPerTick = 250       # Items processed per tick
decay.tickInterval = 256ms        # Base processing interval
decay.bucketInterval = 5min       # Timer wheel bucket size
decay.jitterMaxMs = 25            # ±25ms tick jitter
2026-01-08 11:43:51 -08:00

63 lines
1.4 KiB
C#

using System;
using System.Collections.Generic;
using ModernUO.Serialization;
namespace Server.Items;
[SerializationGenerator(0, false)]
public partial class EffectItem : Item
{
private static Queue<EffectItem> _free = new(); // List of available EffectItems
public static readonly TimeSpan DefaultDuration = TimeSpan.FromSeconds(5.0);
private EffectItem() : base(1) => Movable = false;
public override bool Decays => true;
public override bool SkipSerialization => true;
public static EffectItem Create(Point3D p, Map map, TimeSpan duration)
{
EffectItem item = null;
while (_free.Count > 0)
{
var free = _free.Dequeue();
if (!free.Deleted && free.Map == Map.Internal)
{
item = free;
break;
}
}
if (item == null)
{
item = new EffectItem();
}
else
{
item.ItemID = 1;
}
item.MoveToWorld(p, map);
item.BeginFree(duration);
return item;
}
public void BeginFree(TimeSpan duration) => new FreeTimer(this, duration).Start();
private class FreeTimer : Timer
{
private EffectItem _item;
public FreeTimer(EffectItem item, TimeSpan delay) : base(delay) => _item = item;
protected override void OnTick()
{
_item.Internalize();
_free.Enqueue(_item);
}
}
}