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LagDetector
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LagDetector

by frqmelikescheese · on Modrinth

a simple plugin that adds /lagdetect command to let you see lag sources in your server. Free Minecraft Java mod for 1.21, 1.21.1, 1.21.2.

⬇ Download on Modrinth

🛑⚡ LagDetector: Comprehensive Performance Profiling & Packet Analysis for Paper 1.21.1

LagDetector is a lightweight, low-level, high-impact performance toolkit designed for Paper Minecraft server administrators struggling to pinpoint the exact source of server degradation. While standard performance tools provide general overhead, LagDetector specializes in two distinct, real-time vectors of disruption: physical lag machines (redstone, entities, world bottlenecks) and malicious network packet-level exploits.

With a single command, LagDetector simultaneously generates two real-time diagnostic scores, instantly revealing precisely what is causing lag and where it is located.

🛡️ Core Dual-Layer Intelligence

Standard Lag Monitors LagDetector
Checks general TPS/MSPT only. Checks physical world bottlenecks and incoming raw network packet traffic simultaneously.
Vague; points to "entities." Scans every loaded chunk and every connected player pipeline for specific mathematical hotspots.
Cannot see desync/crash-exploits. Hooks directly into the Netty pipeline to find hidden packet-spam, offhand swaps, desync tools, and crash attempts based on actual network throughput.

🔍 Real-Time Diagnostics

LagDetector's unified /lagdetect command instantly analyzes and ranks the top bottlenecks across your entire server:

Vector A: World & Physical Bottlenecks (Lag Machines)

The plugin performs a deep vertical scan on every loaded chunk. It uses a heavily weighted scoring system (Projectiles > TNT > Hoppers/Pistons > Entities) to find hidden or optimized lag machine clusters:

Vector B: Network & Packet Bottlenecks (Exploits)

LagDetector low-level intercepts the Netty channel adapter for every connection. When diagnostic mode is activated, it calculates the raw incoming data throughput rates. This instantly highlights users running exploit clients or macros designed to spam data to trigger server-wide desync, TPS drops, or client crashes:

⚡ Feature Summary

🚀 Getting Started

  1. Installation: Place LagDetector-1.0.jar into your server's plugins/ directory.
  2. Restart: (Self-injected packet hooks require a full restart or dynamic load).
  3. Permission: Ensure you or your staff group have lagdetector.use.
  4. Use: Run /lagdetect in-game when experiencing TPS degradation or desync to view the results.
Verified by MCModsHub

These come from our own check of the pack file, not from the source page.

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