Incremental Player Save

Implements incremental player saving to smooth out MSPT spikes from saving player data to disk in PlayerManager.saveAllPlayerData()

by ExtraJuiceManGame mechanics Management Optimization

Fabric

Loaders: Fabric
Downloads on Modrinth: 283
Followers on Modrinth: 0
versions: 3
Updated: July 4, 2026Jul 4
Published: in 2026

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At a glance

Runs on Fabric

For Minecraft 1.21.11, 26.1.2–26.2

Server only — players don't need to install it

Latest version — 1.0.1 from July 4, 2026

License MIT — free

Where it's needed

In gamenot neededOn serverrequired

Install on the server only; players don't need it

Game versions1.21.11, 26.1.2–26.2

Incremental Player Save

A mod to eliminate MSPT spikes caused by player data auto-save on Minecraft servers.

What It Does

Minecraft's auto-save calls net.minecraft.server.PlayerManager.saveAllPlayerData() once per save interval, writing every online player's data to disk in a single tick. On servers with many players or with a lot of player data, this can cause a large MSPT spike.

Incremental Player Save fixes this by spreading player saves across multiple ticks, saving a small batch of players per tick rather than all at once. This mod was inspired by Paper's incremental player saving feature.

Who This Is For

Install this mod if you see any of the following:

Regular MSPT spikes every auto-save interval (default: every 6000 ticks / 5 minutes)
net.minecraft.server.PlayerManager.saveAllPlayerData appearing in Spark profiler results during spikes

This mod targets only player .dat file writes. It will not reduce spikes from chunk saving or other auto-save work.

Configuration

All options are in the mod's config file in config/incrementalplayersave.json

Option	Description	Default
`ticksBetweenSaveAttempts`	How often (in ticks) the mod checks which players are due for a save	20
`ticksBetweenSavesPerPlayer`	Minimum ticks between saves for any individual player	6000
`maxPlayersSavedPerAttempt`	Maximum number of players saved per attempt. Controls per-tick save cost	3
`enableDebugLog`	Log save actions to console	`false`

Other Notes

Some optimization mods may include similar functionality. Use Spark to confirm whether saveAllPlayerData still appears in your profiles before installing. On my server with many optimization mods like Lithium, none of them alleviated the tick spike caused by PlayerManager.saveAllPlayerData().
net.minecraft.server.PlayerManager.saveAllPlayerData() is net.minecraft.server.players.PlayerList.saveAll() in Mojang Mappings.

FAQ

How to install Incremental Player Save?

Install Fabric for your Minecraft version, download Incremental Player Save for the same version and loader, put the file into the mods folder and launch the game with the loader profile.

Which Minecraft versions does Incremental Player Save support?

Incremental Player Save has builds for Minecraft 1.21.11, 26.1.2–26.2.

Is Incremental Player Save needed on the server?

Server only — players don't need to install it

License and source

MIT Licensefree to use and share with credit to the author

Original — Modrinth↗Files unchanged, verified with SHA-512Is this your mod? For rights holders