PulseTest

PulseTest is a lightweight Minecraft Paper plugin that lets server operators generate controlled CPU and RAM load to test performance and stability. Run /stress start CPU <percent> or /stress start RAM <percent> to simulate load and observe TPS, MSPT and memory behavior.

Key Features

• Start CPU stress by percentage (1%–400%) to simulate main-thread load (intensity is percent of a 75ms baseline per tick).
• Start RAM stress by percentage of JVM max heap (1%–100%) with retained allocations to pressure the GC.
• Simple commands: /stress start CPU|RAM <percent>, /stress stop (stops all), /stress status (shows current status), /stress reload (reloads config).
• Safety: configurable max OOM events (default 3) — test auto-stops after repeated OOMs.
• Fully server-side, no client mods required.
• Lightweight, focused, and configurable via config.yml.

Functionality

PulseTest provides two compact stressors:

• CPU — busy-waits on the main thread for a configurable fraction of tick time (uses a 75ms baseline). This lets you simulate varying CPU pressure and observe MSPT/TPS effects.
• RAM — allocates and retains memory in small chunks until a target percent of the JVM heap is reached, holding that memory to pressure the garbage collector. The RAM test will auto-stop after repeated OOMs if configured.

Use /stress status to see current allocated MB, targets, and OOM counts.

Installation

PulseTest is a server-side plugin. Drop the built JAR into your plugins folder and restart or reload your server. Edit plugins/PulseTest/config.yml to adjust memory.maxOOMs (default 3) and run /stress reload to apply changes at runtime.

Disclaimer

PulseTest intentionally stresses your server — running high CPU percentages (especially >100% or up to 400%) or targeting near-100% heap can cause large MSPT spikes, OOMs, or crashes. Use with caution on production servers and leave headroom when testing.