Just Enough Threads [JEI Startup Optimize]

Just Enough Threads

Get into your world faster. Just Enough Threads moves JEI's heaviest startup work off the main thread and spreads it across your CPU cores, so large modpacks stop freezing on the loading screen while JEI builds its search index.

What it does

Off-thread ingredient search index

JEI normally builds its ingredient filter — the search index over every item and fluid — on the main thread while you wait on the loading screen. In a big pack that can take several seconds. Just Enough Threads builds it on worker threads after you enter the world, then swaps the finished index into JEI. The result is identical to JEI's own, and if the off-thread build runs into trouble it falls back to JEI's normal build.

What you will see: the JEI item list appears a moment after you spawn, instead of holding up world load.

Parallel recipe ingredient pre-resolution

Before JEI can inspect its built-in recipes (crafting, smelting, stonecutting, and more), every ingredient tag has to be resolved into a concrete list of items. Minecraft does that lazily and JEI triggers all of it during startup. Just Enough Threads does the resolution across CPU cores up front, then hands back to JEI. JEI's own validation and registration still run exactly as they normally do, on the main thread, just against data that is already resolved.

Performance

Measured in a large modpack (roughly 21,000 items and fluids and 34,000 vanilla-type recipes), entering the same world on the same machine with the optimizations off vs on:

JEI startup	Off	On
Building runtime	5.18 s	0.55 s
Starting JEI (total)	10.7 s	6.4 s

The biggest single cost — the ingredient index — no longer blocks loading; it builds in the background once you are already in the world. Numbers vary with hardware and pack size.

Configuration

Config file: config/jei_optimize-client.toml. Every optimization can be toggled independently.

• enabled — master switch for the whole mod.
• asyncIngredientFilter — build the ingredient search index off-thread after world entry.
• parallelVanillaRecipes — resolve recipe ingredients across CPU cores before JEI reads them.

If you ever run into a problem on world entry, turn off the individual options, or set enabled = false to fully restore stock JEI behavior.

Requirements

Minecraft	Loader	JEI
1.20.1	Forge 47.4.4+	15.20.0.120+
1.21.1	NeoForge 21.1.x	19.27.0.340

Client-side only. JEI is required.

Notes

Not affiliated with JEI.

Just Enough Threads

更快进入世界。 Just Enough Threads 把 JEI 启动时最重的工作移出主线程、分散到多个 CPU 核心,让大型整合包在加载界面上不再因为 JEI 构建搜索索引而卡住。

功能

离主线程构建物品搜索索引

JEI 默认在主线程上构建物品筛选器——也就是覆盖所有物品与流体的搜索索引——而你只能在加载界面干等。在大型整合包里,这一步要好几秒。Just Enough Threads 会在你进入世界之后用工作线程构建它,完成后再把成品索引原子替换进 JEI。结果与 JEI 原生完全一致;如果离主线程的构建出现问题,会自动回退到 JEI 的常规构建。

你会看到: JEI 物品列表在你进入世界后稍等片刻才出现,而不是拖慢世界加载。

并行预解析配方材料

JEI 在检查内置配方(合成、熔炼、切石等)之前,需要先把每一条材料标签解析成具体的物品列表。Minecraft 采用惰性解析,而 JEI 启动时会把这些解析全部触发一遍。Just Enough Threads 提前用多个 CPU 核心完成这项解析,再交回 JEI。JEI 自身的校验与注册照常在主线程上运行,只是读到的数据已经解析完毕。

性能

在一个大型整合包(约 21,000 个物品/流体、34,000 条原版类配方)中,于同一台机器进入同一世界,关闭 vs 开启优化:

JEI 启动阶段	关闭	开启
Building runtime	5.18 s	0.55 s
Starting JEI(总计)	10.7 s	6.4 s

最大的单项开销——物品索引——不再阻塞加载;它会在你已经进入世界之后于后台构建。具体数字随硬件与整合包规模而变化。

配置

配置文件:config/jei_optimize-client.toml。每一项优化都可以单独开关。

• enabled — 整个 mod 的总开关。
• asyncIngredientFilter — 进入世界后离主线程构建物品搜索索引。
• parallelVanillaRecipes — 在 JEI 读取之前,用多个 CPU 核心并行解析配方材料。

如果进入世界时遇到任何问题,可以逐项关闭这些选项,或将 enabled = false 以完全恢复 JEI 的原生行为。

需求

Minecraft	Loader	JEI
1.20.1	Forge 47.4.4+	15.20.0.120+
1.21.1	NeoForge 21.1.x	19.27.0.340

仅客户端需要安装,并且必须装有 JEI。

注意事项

本项目与 JEI 无隶属关系。