hi there so i recently was experimenting with mob spawner grinders in game and im not sure if thats the cause but around the same time but server started freaking out causing it to lag.
at com.destroystokyo.paper.event.executor.asm.generated.GeneratedEventExecutor243.execute(Unknown Source) ~[?:?]
at org.bukkit.plugin.EventExecutor.lambda$create$1(EventExecutor.java:69) ~[minecraft_server.jar:git-Paper-135]
at co.aikar.timings.TimedEventExecutor.execute(TimedEventExecutor.java:80) ~[minecraft_server.jar:git-Paper-135]
at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:70) ~[minecraft_server.jar:git-Paper-135]
at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:607) ~[minecraft_server.jar:git-Paper-135]
at net.minecraft.server.v1_16_R1.PlayerConnection.a(PlayerConnection.java:2423) ~[minecraft_server.jar:git-Paper-135]
at net.minecraft.server.v1_16_R1.PacketPlayInWindowClick.a(SourceFile:32) ~[minecraft_server.jar:git-Paper-135]
at net.minecraft.server.v1_16_R1.PacketPlayInWindowClick.a(SourceFile:10) ~[minecraft_server.jar:git-Paper-135]
at net.minecraft.server.v1_16_R1.PlayerConnectionUtils.lambda$ensureMainThread$1(PlayerConnectionUtils.java:23) ~[minecraft_server.jar:git-Paper-135]
at net.minecraft.server.v1_16_R1.TickTask.run(SourceFile:18) ~[minecraft_server.jar:git-Paper-135]
at net.minecraft.server.v1_16_R1.IAsyncTaskHandler.executeTask(IAsyncTaskHandler.java:136) ~[minecraft_server.jar:git-Paper-135]
at net.minecraft.server.v1_16_R1.IAsyncTaskHandlerReentrant.executeTask(SourceFile:23) ~[minecraft_server.jar:git-Paper-135]
at net.minecraft.server.v1_16_R1.IAsyncTaskHandler.executeNext(IAsyncTaskHandler.java:109) ~[minecraft_server.jar:git-Paper-135]
at net.minecraft.server.v1_16_R1.MinecraftServer.aZ(MinecraftServer.java:1137) ~[minecraft_server.jar:git-Paper-135]
at net.minecraft.server.v1_16_R1.MinecraftServer.executeNext(MinecraftServer.java:1130) ~[minecraft_server.jar:git-Paper-135]
at net.minecraft.server.v1_16_R1.IAsyncTaskHandler.awaitTasks(IAsyncTaskHandler.java:119) ~[minecraft_server.jar:git-Paper-135]
at net.minecraft.server.v1_16_R1.MinecraftServer.a(MinecraftServer.java:1204) ~[minecraft_server.jar:git-Paper-135]
at net.minecraft.server.v1_16_R1.MinecraftServer.v(MinecraftServer.java:1001) ~[minecraft_server.jar:git-Paper-135]
at net.minecraft.server.v1_16_R1.MinecraftServer.lambda$a$0(MinecraftServer.java:177) ~[minecraft_server.jar:git-Paper-135]
at java.lang.Thread.run(Thread.java:748) [?:1.8.0_242]
[02:31:16 ERROR]: Could not pass event InventoryClickEvent to Spawners v3.0.3
java.lang.NoSuchMethodError: org.bukkit.inventory.Inventory.getTitle()Ljava/lang/String;
it repeats that every 20 seconds or so, or when someone loads lots of chunks at continually.
i deleted all the man made spawners from my worlds but it hasnt helped
i see now that the problem was a spawner plugin i forgot i installed