Sepals

Sepals

An extremely radical and experimental optimization mod for Minecraft server performances.

We recommend using Sepals with Lithium and Async for optimal performance.

Foreword

First, the Sepals is a collection of highly experimental server-side optimizations that target very specific performance bottlenecks in Minecraft’s AI, entity processing, and task systems. Instead of providing broad “general” optimizations like Lithium, Sepals focuses on deep rewrites of a few extremely expensive vanilla mechanisms — especially villager brains, frog behavior, entity cramming, target filtering, and nearby-entity sensing.

So what does it do in practice?

If you run large farms, villager halls, dense mob enclosures, or any scenario with hundreds/thousands of entities in a small area, Sepals drastically lowers tick time by avoiding Vanilla’s most expensive AI operations.

If you’re running a normal SMP with small farms, you probably won’t notice much of a difference.

It is experimental, and not every optimization is guaranteed to have Vanilla parity, but in performance-stress tests, the gains can be huge.

Compatibility

Currently, Sepals is compatible with nearly all mods.

Here is the verified mod list with the latest Sepals version:

| Target mod | Required target version | |------------------------------------------------------:|:-----------------------:| | Sodium | all | | Iris | all | | FerriteCore | all | | Krypton | all | | Lithium | >=0.18.0 | | C2ME | \>=0.3.4.0.0 | | Moonrise | \>=0.6.0-beta.1+45edfd7 | | Async | \>=0.1.7+alpha.7-1.21.8 |

If you don't know which version to choose, please use the latest version of optimization mods, as Sepals will ensure compatibility with them.

Important

Sepals won't support any old versions and snapshot versions of Minecraft; all bug fixes and features are only available in the newest version.

When using it with Async, please manually compare performance with Sepals and Async, and edit their configurations, to find which optimizations are worthwhile, as each machine has different results.

Sepals feature related: ``enableSepalsEntitiesCramming``.

Config

| Config name | Allowed value | Default value | |:-------------------------------------------:|:-------------:|:-------------:| | forceEnableSepalsPoi | bool value | false | | enableSepalsVillager | bool value | true | | enableSepalsFrogLookAt | bool value | true | | enableSepalsFrogAttackableSensor | bool value | true | | enableSepalsLivingTargetCache | bool value | true | | nearestLivingEntitiesSensorUseQuickSort | bool value | true | | enableSepalsBiasedLongJumpTask | bool value | true | | enableSepalsEntitiesCramming | bool value | true | | enableSepalsItemMerge | bool value | true | | enableSepalsQuickCanBePushByEntityPredicate | bool value | true |

Performance

A test was done in server of Mars provided by feimia, CPU: Intel i7-14700K; Game memory: 4G; OS: Ubuntu 24.04.1 LTS; Minecraft: 1.21.

Entities cramming

Use box cache to prevent too much 'getOtherEntities' calls

-- Notice --
This feature ignores scoreboard/team predicates for every single entity
and may cause unexpected behavior.

This problem will not affect anything in Vanilla, except when using
command blocks.

-- Status --
Enabled by default

1390 villagers cramming in a 7x7 space:

| Environment | tickCramming | Percent (Avg.) | |--------------------:|:------------:|:-------------:| | Vanilla | 53.6 ms | 100 % | | Lithium | 54.4 ms | 101 % | | Sepals | 10.2 ms | 19 % | | Sepals + Lithium | 8.5 ms | 15 % |

Weighted random

Use binary search to replace vanilla weight random

-- Warning --
This feature may not be worthwhile,
as Spark proved that it is slower than Vanilla when constructing range tables,
even if the binary search is close to 0 ms.

-- Status --
Disabled by default

-- Warning -- 
Not tested.

Biased long jump task

Use Sepals long jump task implementation to replace Vanilla

As mentioned above, the binary search is almost no costs
sepals impletation will construct the range table at the same time as generating targets
and used Catheter to replaced java stream

The same time, rearrange should jump conditions in frog brain, make a good performance

-- Notice --
This feature is unable to change in game runtime
required restart the server to apply changes

-- Status --
Enabled by default

800 frogs cramming in a 7x7 space: