Don't tick markers (#7299)

patches/server/0904-Don-t-tick-markers.patch

@@ -0,0 +1,48 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Noah van der Aa <ndvdaa@gmail.com>
+Date: Fri, 7 Jan 2022 11:58:26 +0100
+Subject: [PATCH] Don't tick markers
+
+Fixes https://github.com/PaperMC/Paper/issues/7276 by not adding markers to the entity
+tick list at all and ignoring them in Spigot's activation range checks. The entity tick
+list is only used in the tick and tickPassenger methods, so we can safely not add the
+markers to it.
+
+diff --git a/src/main/java/com/destroystokyo/paper/PaperCommand.java b/src/main/java/com/destroystokyo/paper/PaperCommand.java
+index d0c55497040158d959693ef2ddf3ff03bd6df05f..45d1807b31f5acd5f08f729701cec4b464ad9398 100644
+--- a/src/main/java/com/destroystokyo/paper/PaperCommand.java
++++ b/src/main/java/com/destroystokyo/paper/PaperCommand.java
+@@ -614,7 +614,7 @@ public class PaperCommand extends Command {
+                     ChunkPos chunk = e.chunkPosition();
+                     info.left++;
+                     info.right.put(chunk, info.right.getOrDefault(chunk, 0) + 1);
+-                    if (!chunkProviderServer.isPositionTicking(e)) {
++                    if (!chunkProviderServer.isPositionTicking(e) || e instanceof net.minecraft.world.entity.Marker) { // Markers aren't ticked.
+                         nonEntityTicking.merge(key, Integer.valueOf(1), Integer::sum);
+                     }
+                 });
+diff --git a/src/main/java/net/minecraft/server/level/ServerLevel.java b/src/main/java/net/minecraft/server/level/ServerLevel.java
+index 50fd3419deb668dda64b1056f03fb66da55e6960..62ec40de8ed8acb293ef21c8d2c624060d51cfe8 100644
+--- a/src/main/java/net/minecraft/server/level/ServerLevel.java
++++ b/src/main/java/net/minecraft/server/level/ServerLevel.java
+@@ -2418,6 +2418,7 @@ public class ServerLevel extends Level implements WorldGenLevel {
+         }
+ 
+         public void onTickingStart(Entity entity) {
++            if (entity instanceof net.minecraft.world.entity.Marker) return; // Paper - Don't tick markers
+             ServerLevel.this.entityTickList.add(entity);
+             ServerLevel.this.entityManager.addNavigatorsIfPathingToRegion(entity); // Paper - optimise notify
+         }
+diff --git a/src/main/java/org/spigotmc/ActivationRange.java b/src/main/java/org/spigotmc/ActivationRange.java
+index 5bffc9a0f6ef9d54abb359565d07509b177c2b82..1a1a1f4d0ac025daccc2d3f84faf6592819f4d5c 100644
+--- a/src/main/java/org/spigotmc/ActivationRange.java
++++ b/src/main/java/org/spigotmc/ActivationRange.java
+@@ -211,7 +211,7 @@ public class ActivationRange
+             // Paper end
+ 
+             // Paper start
+-            java.util.List<Entity> entities = world.getEntities((Entity)null, maxBB, null);
++            java.util.List<Entity> entities = world.getEntities((Entity)null, maxBB, (e) -> !(e instanceof net.minecraft.world.entity.Marker)); // Don't tick markers
+             for (int i = 0; i < entities.size(); i++) {
+                 Entity entity = entities.get(i);
+                 ActivationRange.activateEntity(entity);