Weird Ars Magica Essence system crash

[Axolotl9250]

Hi, I was playing on Magic World 2 and I had just tried to connect up a mana battery from AM2 with a light nexus, and also connect the battery to the essence refiner, when my game crashed and now when I try to play the world again it crashes as soon as is loaded, reporting these error lines to STDOUT. I hope somebody else knows what this is doing I'd rather not have to loose the world.
Best,
Ben.

2014-04-18 01:36:23 [SEVERE] [Minecraft-Server] Encountered an unexpected exception ReportedException
net.minecraft.util.ReportedException: Ticking tile entity
    at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:674)
    at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:587)
    at net.minecraft.server.integrated.IntegratedServer.func_71217_p(IntegratedServer.java:129)
    at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:484)
    at net.minecraft.server.ThreadMinecraftServer.run(SourceFile:583)
Caused by: java.lang.StackOverflowError
    at net.minecraft.world.ChunkPosition.hashCode(SourceFile:30)
    at java.util.HashMap.get(Unknown Source)
    at net.minecraft.world.chunk.Chunk.func_76597_e(Chunk.java:971)
    at net.minecraft.world.World.func_72796_p(World.java:2865)
    at am2.blocks.tileentities.TileEntityAMPower.pointIsPowerSource(TileEntityAMPower.java:454)
    at am2.blocks.tileentities.TileEntityAMPower.requestPower(TileEntityAMPower.java:390)
    at am2.blocks.tileentities.TileEntityAMPower.consumePower(TileEntityAMPower.java:357)
    at am2.blocks.tileentities.TileEntityAMPower.requestPower(TileEntityAMPower.java:402)
    at am2.blocks.tileentities.TileEntityAMPower.consumePower(TileEntityAMPower.java:357)
    at am2.blocks.tileentities.TileEntityAMPower.requestPower(TileEntityAMPower.java:402)
    ... and again and again and again.

 

[YX33A]

A common solution for this sort of error is to just remove the mod that is causing it. People love to hack out a tumor with an axe when a scalpel will do.

Open your forge.cfg file located in whatever instance/pack you use(that is, "Pack/Instance"/minecraft/config/forge.cfg) and find these lines. Note: I have no idea which one will fix this, so unless you do, use them both and set them back afterwords.

Emptor cavete, etc etc.

# Set this to just remove any TileEntity that throws a error in there update method instead of closing the server and reporting a crash log. BE WARNED THIS COULD SCREW UP EVERYTHING USE SPARINGLY WE ARE NOT RESPONSIBLE FOR DAMAGES.
  B:removeErroringEntities=false

  # Set this to just remove any TileEntity that throws a error in there update method instead of closing the server and reporting a crash log. BE WARNED THIS COULD SCREW UP EVERYTHING USE SPARINGLY WE ARE NOT RESPONSIBLE FOR DAMAGES.
  B:removeErroringTileEntities=false

Set them to true and hopefully this fixes it without ruining too much of your world. Note: You're likely gonna lose at least one of those things, maybe all of them.

 

[Axolotl9250]

Hi I found opening my world in MCEDIT and remove the cheaper block in the power system chain causing the problem solved the issue. since the power system was then broken and wouldnt trigger whatever loop I'm guessing caused the stack overflow. This worked until I later built another essence power thing (slipstream generator for anyone interested) and then checkit it's power level with my staff and then it crashed again, but the system that crashed previous, with the battery and refiner, worked without crashing! So it seems the stack overflow condition is only generated under certain conditions. I'm worried the above suggestion will end up just cutting out all the AM2 essence system and make a large part of the mod useless.

 

[YX33A]

Hi I found opening my world in MCEDIT and remove the cheaper block in the power system chain causing the problem solved the issue. since the power system was then broken and wouldnt trigger whatever loop I'm guessing caused the stack overflow. This worked until I later built another essence power thing (slipstream generator for anyone interested) and then checkit it's power level with my staff and then it crashed again, but the system that crashed previous, with the battery and refiner, worked without crashing! So it seems the stack overflow condition is only generated under certain conditions. I'm worried the above suggestion will end up just cutting out all the AM2 essence system and make a large part of the mod useless.

...See here, this is people using the axe when the scalpel will suffice. That suggestion I made would remove a erroring tile entity instead of crashing the game, and if you use it sparingly, it is indeed, using the scalpel. You took MCEdit to the problem, which isn't that much worse then what I suggested(in fact, you lucked out at guessing what caused the issue, if you found it at all). But you went at the issue with all the grace of a monster truck when you needed that of a surgeon, which I told you how to use.

 

[Axolotl9250]

Alright, fine I appreciate your suggestion very much - more than I do being talked at sarcastically like some sort of neonate. I used MCedit before your suggestion on here came up - and not knowing much in depth about mine-craft or Java or Forge's inner workings, and most of my programming knowledge aimed at the high level functional scientific analysis languages and that's all - removing one block - seemed the better option than removing the entire mod. And as the block was acting weird and being difficult before the crash, and given the error messages said "am2" and "power" in them, it seemed sensible it was what I was trying to do with those powered blocks that did it. Also given the cfg file in forge has big bold warning messages - and the fact I'm not 100% sure what a tiling entity is - perhaps it is not synonymous with block as would be my first guess. Removing the offending block instance from my save and trying again (it worked the second time) seemed a sensible option cf losing the world or not using AM2 at all any-more. I'll try the forge.cfg changes you suggest now though.

 

[YX33A]

I'm a jerk first, and helpful second. You hopefully solved the issue, but you have less info then the game itself does, and merely removing "the least expensive" block isn't likely the correct answer(though if in this case any one of this is actually pretty cheap, with the exception of the essence refiner using some obsidian).

That said, you had it right, it is dangerous... but so is using MCEdit to try and fix this issue. And Forge can remove any and all erroring TE's around you in one go, and MCEdit only removes blocks you tell it to remove.
Anyway, a Tile Entity is a Block that has data beyond appearance. So for example a Chest is, as is a Furnace, and so is any block that has a GUI or does something aside from look pretty. But even those ones that only look pretty can have data attached to them, actually. For example, any sort of Microblock is a tile entity, actually.

It usually doesn't account for much unless you use a lot of them or they are poorly coded. For examples of these, look at what happens with too many microblocks being used at once, or with OpenBlocks Tanks when you use a lot of them.

 

[Axolotl9250]

It was very helpful thank you - the thing that got removed by forge in the end was the essence refiner - I dunno if that's going to be a bug that keeps appearing every time or if it's just that instance of the refiner that screwed up. I've watched other people use it without issue. Thanks for the explanation - I hope to read the modding documentation for minecraft and other such resources over Easter.

 

[YX33A]

It was very helpful thank you - the thing that got removed by forge in the end was the essence refiner - I dunno if that's going to be a bug that keeps appearing every time or if it's just that instance of the refiner that screwed up. I've watched other people use it without issue. Thanks for the explanation - I hope to read the modding documentation for minecraft and other such resources over Easter.

Ars Magicka 2 has some very lax online documentation, but it has decent in game documentation. But when issues like this crop up, well, sometimes the only option is ask on some forums.
Like you did. Wise man.

...Anyway, I'd suggest not being to offput by the essence refiner derping on you; try, try again. Just be careful, and when issues crop up, at least now you have some experience and some extra tools in your arsenal.