DarkTimer
DarkTimer is a server-side mod that automatically clears dropped items from the ground, helping to significantly reduce lag caused by excessive entities on the server.
Main Features
On modded servers, a common issue occurs when dropped items fail to despawn after the standard 5 minutes. This leads to entity accumulation and serious performance degradation. DarkTimer solves this problem by automatically clearing all ground items every 10 minutes.
The system provides two warning notifications before cleanup: 10 minutes and 1 minute before item removal. This allows players to retrieve valuable items if they were accidentally dropped.

Configuration and Compatibility
The mod is fully compatible with server-only installation — it can be installed solely on the server, and clients don't require additional installation. The cleanup interval can be customized using datapacks available in the developers' Discord community.
The screenshot below demonstrates stable server performance with 31 players on the official DarkRPG server:

The developers permit free usage of the mod in modpacks. The mod is created by the authors of the popular DarkRPG modpack, which offers complete RPG gameplay with quests and expanded features.