I need help

---- Minecraft Crash Report ----

WARNING: coremods are present:
SpongeCoremod (spongeforge-1.10.2-2477-5.2.0-BETA-2637 (1).jar)
Contact their authors BEFORE contacting forge

// Hey, that tickles! Hehehe!

Time: 10/14/17 11:35 AM
Description: Watching Server

java.lang.Error
at java.util.TreeMap.successor(TreeMap.java:2157)
at java.util.TreeMap$PrivateEntryIterator.nextEntry(TreeMap.java:1208)
at java.util.TreeMap$KeyIterator.next(TreeMap.java:1261)
at net.minecraft.world.WorldServer.func_175712_a(WorldServer.java:799)
at net.minecraft.world.WorldServer.func_72920_a(WorldServer.java:776)
at net.minecraft.world.chunk.storage.AnvilChunkLoader.func_75820_a(AnvilChunkLoader.java:396)
at net.minecraft.world.chunk.storage.AnvilChunkLoader.func_75816_a(AnvilChunkLoader.java:175)
at net.minecraft.world.gen.ChunkProviderServer.func_73242_b(ChunkProviderServer.java:199)
at net.minecraft.world.gen.ChunkProviderServer.func_186027_a(ChunkProviderServer.java:227)
at net.minecraft.world.WorldServer.func_73044_a(WorldServer.java:1013)
at org.spongepowered.common.world.WorldManager.saveWorld(WorldManager.java:535)
at net.minecraft.server.MinecraftServer.func_71267_a(MinecraftServer.java:3886)
at net.minecraft.server.MinecraftServer.constant$getSaveTickInterval$zhp000(MinecraftServer.java:3841)
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:632)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:471)
at java.lang.Thread.run(Thread.java:745)

A detailed walkthrough of the error, its code path and all known details is as follows:

– Head –
Thread: Server Watchdog
Stacktrace:
at java.util.TreeMap.successor(TreeMap.java:2157)
at java.util.TreeMap$PrivateEntryIterator.nextEntry(TreeMap.java:1208)
at java.util.TreeMap$KeyIterator.next(TreeMap.java:1261)
at net.minecraft.world.WorldServer.func_175712_a(WorldServer.java:799)
at net.minecraft.world.WorldServer.func_72920_a(WorldServer.java:776)
at net.minecraft.world.chunk.storage.AnvilChunkLoader.func_75820_a(AnvilChunkLoader.java:396)
at net.minecraft.world.chunk.storage.AnvilChunkLoader.func_75816_a(AnvilChunkLoader.java:175)
at net.minecraft.world.gen.ChunkProviderServer.func_73242_b(ChunkProviderServer.java:199)
at net.minecraft.world.gen.ChunkProviderServer.func_186027_a(ChunkProviderServer.java:227)
at net.minecraft.world.WorldServer.func_73044_a(WorldServer.java:1013)
at org.spongepowered.common.world.WorldManager.saveWorld(WorldManager.java:535)

– Sponge CauseTracker –
Details:
Cause Stack: [Empty stack]
Stacktrace:
at net.minecraft.server.MinecraftServer.handler$onCrashReport$zhp000(MinecraftServer.java:3953)
at net.minecraft.server.MinecraftServer.func_71230_b(MinecraftServer.java:829)
at net.minecraft.server.dedicated.DedicatedServer.func_71230_b(DedicatedServer.java:361)
at net.minecraft.server.dedicated.ServerHangWatchdog.run(ServerHangWatchdog.java:62)
at java.lang.Thread.run(Thread.java:745)

– Thread Dump –
Details:
Threads: “process reaper” Id=580 TIMED_WAITING on java.util.concurrent.SynchronousQueue$TransferStack@65b4c073
at sun.misc.Unsafe.park(Native Method)
- waiting on java.util.concurrent.SynchronousQueue$TransferStack@65b4c073
at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215)
at java.util.concurrent.SynchronousQueue$TransferStack.awaitFulfill(SynchronousQueue.java:460)
at java.util.concurrent.SynchronousQueue$TransferStack.transfer(SynchronousQueue.java:362)
at java.util.concurrent.SynchronousQueue.poll(SynchronousQueue.java:941)
at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1066)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)

raise the max-tick-time in the server.properties, this crash is caused when a single tick took too long, in this case probably due to worldgen