From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Bacteriawa <A3167717663@hotmail.com>
Date: Tue, 21 Apr 2026 01:41:14 +0800
Subject: [PATCH] Kaiiju: Entity tick and removal limiter

Co-authored by: Xymb <xymb@endcrystal.me>
As part of: Kaiiju (https://github.com/KaiijuMC/Kaiiju/blob/c2b7aec8f7b418a39a2ec408e6411e6f752379da/patches/server/0021-Entity-ticking-throttling-removal-to-prevent-lag.patch)
Licensed under: GPL-3.0 (https://github.com/KaiijuMC/Kaiiju/blob/c2b7aec8f7b418a39a2ec408e6411e6f752379da/LICENSE)

diff --git a/io/papermc/paper/threadedregions/RegionizedWorldData.java b/io/papermc/paper/threadedregions/RegionizedWorldData.java
index cb15cfbc684ae9e9d9634886f707c2df10063139..f32d118e1e925b2155cef3fcdcb1e194c541e242 100644
--- a/io/papermc/paper/threadedregions/RegionizedWorldData.java
+++ b/io/papermc/paper/threadedregions/RegionizedWorldData.java
@@ -354,6 +354,7 @@ public final class RegionizedWorldData {
     private final IteratorSafeOrderedReferenceSet<Mob> navigatingMobs = new IteratorSafeOrderedReferenceSet<>();
     public final ReferenceList<Entity> trackerEntities = new ReferenceList<>(EMPTY_ENTITY_ARRAY); // Moonrise - entity tracker
     public final ReferenceList<Entity> trackerUnloadedEntities = new ReferenceList<>(EMPTY_ENTITY_ARRAY); // Moonrise - entity tracker
+    public final dev.kaiijumc.kaiiju.KaiijuEntityThrottler entityThrottler = new dev.kaiijumc.kaiiju.KaiijuEntityThrottler(); // Kaiiju
 
     // block ticking
     private final ObjectLinkedOpenHashSet<BlockEventData> blockEvents = new ObjectLinkedOpenHashSet<>();
diff --git a/net/minecraft/server/level/ServerLevel.java b/net/minecraft/server/level/ServerLevel.java
index 39e511061d11039a1027320de624be07e34a2978..0097c55adf5578f425b476b3498db1c701189e4b 100644
--- a/net/minecraft/server/level/ServerLevel.java
+++ b/net/minecraft/server/level/ServerLevel.java
@@ -910,6 +910,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
             }
 
             foliaProfiler.startTimer(ca.spottedleaf.leafprofiler.LProfilerRegistry.ACTIVATE_ENTITIES); try { // Folia - profiler
+                if (dev.kaiijumc.kaiiju.KaiijuEntityLimits.enabled) regionizedWorldData.entityThrottler.tickLimiterStart(); // Kaiiju
             io.papermc.paper.entity.activation.ActivationRange.activateEntities(this); // Paper - EAR
             } finally { foliaProfiler.stopTimer(ca.spottedleaf.leafprofiler.LProfilerRegistry.ACTIVATE_ENTITIES); } // Folia - profiler
             foliaProfiler.startTimer(ca.spottedleaf.leafprofiler.LProfilerRegistry.ENTITY_TICK); try { // Folia - profiler
@@ -931,6 +932,13 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
 
                                         entity.stopRiding();
                                     }
+                                    // Kaiiju start
+                                    if (dev.kaiijumc.kaiiju.KaiijuEntityLimits.enabled) {
+                                        dev.kaiijumc.kaiiju.KaiijuEntityThrottler.EntityThrottlerReturn throttle = regionizedWorldData.entityThrottler.tickLimiterShouldSkip(entity);
+                                        if (throttle.remove && !entity.hasCustomName()) entity.remove(Entity.RemovalReason.DISCARDED);
+                                        if (throttle.skip) return;
+                                    }
+                                    // Kaiiju end
 
                                     profiler.push("tick");
                                     this.guardEntityTick(this::tickNonPassenger, entity);
@@ -940,6 +948,7 @@ public class ServerLevel extends Level implements WorldGenLevel, ServerEntityGet
                         }
                     }
                 );
+                if (dev.kaiijumc.kaiiju.KaiijuEntityLimits.enabled) regionizedWorldData.entityThrottler.tickLimiterFinish(regionizedWorldData); // Kaiiju
             } finally { foliaProfiler.stopTimer(ca.spottedleaf.leafprofiler.LProfilerRegistry.ENTITY_TICK); } // Folia - profiler
             if (this.paperConfig().unsupportedSettings.ticking.blockEntities) { // Paper - option to disable ticking
             profiler.popPush("blockEntities");