Entity Keepsake

Entity Keepsake: FPS boost for armor stands, holograms and NPCs

Entity Keepsake is a client-side performance mod for Fabric that fixes entity lag. If your FPS drops in crowded places full of armor stands, holograms, NPCs, item frames or display entities, this mod is for you. It was built for the Hypixel SkyBlock hub, where hundreds of hologram stands and player NPCs pull FPS down, but it boosts performance on any server or world with lots of still entities.

Nothing is hidden, culled or removed. Every entity is still drawn every frame, so the game looks exactly the same. It just runs faster.

Up to 63% more FPS in crowded areas

Tested on a 112-mod Hypixel SkyBlock modpack in a crowded scene full of hologram stands and player NPCs (median of interleaved runs):

	Average FPS	1% low FPS
Without Entity Keepsake	52.4	40.4
With Entity Keepsake	85.3	57.2

Better 1% lows mean fewer stutters and smoother frame times, not just a higher number. Your gain depends on how many still entities are on screen and on your PC: it's biggest in busy hubs and NPC areas, and small in an empty world.

Why armor stands and holograms cause lag

Every frame, Minecraft rebuilds every visible entity from scratch, even an armor stand that hasn't moved in an hour. Servers like Hypixel use stacks of invisible armor stands for every hologram, NPC name and floating label, so a single hub can have hundreds of them. Rebuilding all of them every frame takes a lot of CPU time on the render thread, and that's where the FPS goes.

Entity Keepsake keeps the work for entities that haven't changed and reuses it on the next frame.

What it optimizes

• Armor stands: invisible, marker, small and named armor stands.
• Holograms and floating text: hologram stacks, NPC name tags and floating labels made from armor stands.
• NPCs: Hypixel's player-shaped NPCs, mannequins, and real players standing still. Your own player is never touched.
• Item frames: item frames with items in them (maps are left alone).
• Display entities: block displays, item displays and text displays, including ones that turn to face you.

How it works

Entity Keepsake speeds up entity rendering at four levels:

1. Render state caching: the description of how an entity should look is reused instead of rebuilt every frame.
2. Name tag layout caching: the text layout of name tags and holograms is kept and reused.
3. Vertex replay: the finished geometry of still armor stands, heads, shields and items is copied in again, shifted for camera movement, instead of being recalculated.
4. Armor stand draw replay: for a still armor stand, the list of things it draws is recorded and replayed, instead of running its renderer and every mod hooked into it again.

Nothing is reused on trust. Geometry and draw lists are only replayed after two normal builds in a row came out exactly the same.

Looks exactly like vanilla

• Anything that moves is rebuilt. Position, rotation, head turns, animations, riding, invisibility and display updates are checked every frame.
• Time-based entities are never cached. Entities that are moving, hurt, dying, swinging, on fire, on a lead, or holding a clock or compass are always rendered normally. So is the entity under your crosshair.
• Glowing entities and highlights work. Outline colours are worked out the same way vanilla does, so SkyHanni and Skyblocker highlights still show.
• Name tags never lag behind the camera. They're always drawn live, so mods that change labels as they're drawn keep working.
• Safety net: every cached entity is rebuilt from scratch at least once a second, so a change the checks miss still shows up within a second.

Glow, team colour, lighting and skin changes are checked every 5 game ticks instead of every frame. These only change on game ticks anyway, so at worst one shows up a quarter of a second late.

Compatible with Sodium and popular SkyBlock mods

Tested in a 112-mod Hypixel SkyBlock modpack with Sodium, Lithium, ImmediatelyFast, Entity Culling, More Culling, SkyHanni, Skyblocker, Odin, Entity Model Features (EMF), Entity Texture Features (ETF), Catharsis, 3D Skin Layers, Not Enough Animations and Subtle Effects.

A built-in self-check compared every reused result with a freshly built one in that pack, with the camera both still and turning: 8,669,909 checks, 0 differences.

The FPS results above were measured with those performance mods already installed, so Entity Keepsake adds on top of them. Culling mods skip entities you can't see. Entity Keepsake speeds up the ones you can, so they stack.

Commands and config

• /entitykeepsake: shows how many entities were reused or rebuilt.
• /entitykeepsake on and /entitykeepsake off: turn the mod on or off in game, handy for comparing FPS.
• /entitykeepsake reset: resets the counters.
• /entitykeepsake verify: a self-check that compares every reused result with a freshly built one and lists any difference. It's slow, so turn it off when you're done.

In config/entitykeepsake.properties, enabled=false turns everything off. You can turn off single parts with name_tag_layouts=false, vertex_replay=false, name_tag_replay=false and submit_replay=false.

FAQ

Does it hide or cull entities? No. Every entity is still drawn every frame. It only skips redoing work for entities that haven't changed.

Does it work on Hypixel? It was built for Hypixel SkyBlock and tested there. It's client-side only and doesn't change gameplay or give any advantage. It only makes your game draw entities faster.

Does it work on other servers and in singleplayer? Yes. Any world with lots of armor stands, holograms, NPCs, item frames or display entities benefits, like lobbies, hubs, spawn areas and builds full of decorations.

Do I need it on the server? No. Install it on your client only.

Is it an alternative to Fast Static Entity? Yes. Entity Keepsake is an open-source, clean-room remake of Fast Static Entity that also covers named armor stands (holograms), player NPCs, billboarded display entities and glowing entities.

Something looks wrong. What do I do? Run /entitykeepsake verify to see if the mod finds a difference, and /entitykeepsake off to check if the mod is the cause. Please report it either way.

Known limits

• A mod that changes how an entity looks over time while it's drawn, using data this mod doesn't know about, can look up to a second behind on still entities. /entitykeepsake verify will show it, and /entitykeepsake off fixes it.
• Item models driven by something other than the clock or compass (such as the time of day) aren't detected.

Requirements

• Minecraft 26.2
• Fabric Loader 0.19 or newer
• Fabric API
• Client-side only

About

Entity Keepsake is open source under the MIT license. It's a clean-room remake of Fast Static Entity, written only from a description of how the original behaves, without looking at its code. Formerly called Static Entities.