Lumbermill calculation slows down savegame load

[RoyCurtis]

It appears that the ExtraTrees Lumbermill performs a heavy calculation to determine plank products, every time a dimension is loaded. In modpacks such as Direwolf20, this causes each dimension to take up to 2 seconds to load. In my case, my server with many RFTools and Mystcraft ages incurs a 30 second delay during loading.

Tested on

• Minecraft 1.7.10 Forge 10.13.4.1448
• Direwolf20 1.5.0
• Binnie's Mods 2.0 pre12

Screenshots

• Java Flight Recorder snapshot of a single dimension loading, with Lumbermill hot methods highlighted
• Same snapshot, with entire 30 second period selected

Reproduction

1. Launch a modpack with console open
2. Create a new world and enter it
3. Allow Minecraft to generate the new world, and then quit to menu
4. Re-open the newly created world
5. Observe on the console; when Forge begins loading dimensions (e.g. Loading dimension -42 (world) (net.minecraft.server.integrated.IntegratedServer@6524cde7)), note the delay of a few seconds for each dimension

Suggested fixes

Ideally, this calculation should only be performed once; either in a different event than onWorldLoad, or by checking if the calculation has already been performed.

[Alex Binnie]

Fixed in pre13

[RoyCurtis]

Thank you very much for the quick resolution! Appreciated as always