PulseNet
The Heartbeat of High-Performance Networking - Fabric Edition by BorisShoes
PulseNet is a Fabric mod that brings high-performance packet batching to your Minecraft server. By replacing standard per-packet network flushes with intelligent batching, PulseNet reduces system call overhead and CPU usage while maintaining low-latency delivery of critical packets.
Project Overview
PulseNet is a Fabric mod that replaces Minecraft's default per-packet network flushing with a smart batching system. Outgoing packets are grouped and flushed together, drastically reducing kernel syscall overhead and event loop task scheduling while keeping combat, chat, and other latency-sensitive packets instant. Designed to work seamlessly alongside other Fabric mods via Mixin compatibility.
Installation
PulseNet is a server-side Fabric mod. Drop it into your mods/ folder alongside Fabric API.
Requirements:
Features
| Feature |
Description |
| Smart Packet Batching |
Groups outgoing packets within a tick and flushes them in a single kernel syscall instead of one per packet. Supports three modes: smart_execution, strict_tick, and interval. |
| Write Queue |
Replaces per-packet event loop task submissions with a single batched write task, eliminating lambda allocations and cross-thread scheduling overhead. |
| Packet Coalescing |
Bundles similar low-priority packets (particles, sounds) into BundlePackets, reducing the client's received packet count. |
| Explosion Optimization |
Detects mass block changes from explosions and replaces individual block update packets with a full chunk resend when a configurable threshold is exceeded. |
| Packet Classification |
Automatically classifies packets as Critical, Instant, Chat, Ignored, or Coalesce — ensuring latency-sensitive packets (keepalive, disconnect, combat) always bypass the buffer. Fabric infrastructure packets (minecraft:register, minecraft:unregister) are handled at the Connection level to prevent mod handshake failures. |
| Real-Time Metrics |
Built-in metrics system tracking logical/physical PPS, bandwidth, CPU usage, memory savings, and write queue efficiency. Viewable via commands or an in-game boss bar. |
| Mixin Compatibility |
Uses a @WrapOperation approach that runs after all other mixins (Polymer, server-side translations, etc.), ensuring full compatibility with the Fabric mod ecosystem. |
| Hot-Reloadable Config |
All settings are configurable via pulse.properties and in-game commands (/pulse config, /pulse reload) with no restart required. |
Commands
| Command |
Description |
/pulse |
Displays the current PulseNet version. |
/pulse reload |
Reloads the configuration from disk. |
/pulse config |
View and modify all configuration settings in-game. |
/pulse netstats [network\|cpu\|ram\|all] |
Displays real-time network, CPU, and memory statistics. |
/pulse netstats bar |
Toggles the metrics boss bar overlay. |
/pulse netstats reset |
Resets all metrics counters to zero. |
/pulse packetNames |
Lists all observed packet class names and channel IDs. |
/pulse packetNames classes |
Lists only observed packet class names. |
/pulse packetNames channels |
Lists only observed custom payload channel IDs. |
/pulse packetNames reset |
Clears the observed packet name lists. |
Config Commands
The following commands can be used to adjust configurable settings in the pulse.properties file without a server reboot (Use /pulse reload after running these commands to hotswap changes). These commands can be suffixed with a value to set the setting, or used without a value to view the current setting.
/pulse config batchingEnabled Master toggle for the smart packet batching system. When true, outgoing packets are buffered and flushed in batches instead of individually. (default: true)/pulse config batchingMode Batching mode: smart_execution (flush on tick + limits), strict_tick (flush only on tick end), interval (flush on a timer). (default: smart_execution)/pulse config batchingMaxBatchSize Maximum number of packets to buffer before forcing a flush. (default: 1024)/pulse config batchingMaxBatchBytes Maximum bytes to buffer before forcing a flush. (default: 32000)/pulse config batchingFlushInterval Interval in milliseconds for the INTERVAL batching mode. (default: 25)/pulse config batchingSafetyMarginBytes Safety margin in bytes subtracted from the max batch bytes limit to prevent overflow. (default: 64)/pulse config batchingInstantPackets List of packet class names that should flush the buffer immediately when sent. (default: ClientboundHurtAnimationPacket, ClientboundDamageEventPacket, ClientboundBlockEntityDataPacket)/pulse config batchingIgnoredPackets List of packet class names that should always bypass the buffer entirely. (default: [])/pulse config batchingInstantChannels List of plugin channel IDs (e.g. axiom:hello) whose custom payload packets should flush the buffer immediately when sent. Use /pulse packetNames channels to discover channel IDs. (default: [])/pulse config batchingIgnoredChannels List of plugin channel IDs whose custom payload packets should always bypass the buffer entirely. Use /pulse packetNames channels to discover channel IDs. Note: minecraft:register and minecraft:unregister are handled at the Connection level and always bypass the buffer regardless of this list. (default: [])/pulse config batchingChatPacketsBypass When true, chat-related packets bypass the buffer for instant delivery. (default: true)/pulse config batchingOffThreadBypass When true, packets sent from off the server thread bypass the buffer. (default: true)/pulse config batchingWriteQueue When true, buffered packets are queued and written in a single event loop task instead of calling Connection.send() per packet, eliminating per-packet lambda allocations and cross-thread task scheduling. (default: true)/pulse config batchingPacketCoalescing When true, packets in the coalesce list are bundled together into BundlePackets on flush, reducing the client's received packet count. (default: true)/pulse config batchingCoalescePackets List of packet class names to coalesce into BundlePackets (e.g. particles, sounds). Supports inner classes with dot syntax (Foo.Bar). (default: ClientboundLevelParticlesPacket, ClientboundSoundPacket, ClientboundSoundEntityPacket)/pulse config batchingCoalesceBundleLimit Maximum number of sub-packets per BundlePacket. Vanilla client enforces a hard limit of 4096. (default: 4000)/pulse config optExplosionsEnabled When true, block updates from explosions are grouped by chunk and replaced with full chunk resends if they exceed the threshold. (default: true)/pulse config optExplosionsBlockChangeThreshold Number of block changes in a single chunk required to trigger a full chunk resend instead of individual updates. (default: 512)/pulse config optExplosionsLogOptimizations When true, logs a message each time the explosion optimization replaces block updates with a chunk resend. (default: false)/pulse config metricsEnabled When true, the metrics collection system is active and computes network statistics. (default: true)/pulse config metricsUpdateInterval How often (in seconds) the metrics system recomputes derived statistics. (default: 1)/pulse config metricsModuleNetwork Enables the network metrics module (PPS, bandwidth). (default: true)/pulse config metricsModuleCpu Enables the CPU metrics module (process CPU usage estimation). (default: true)/pulse config metricsModuleMemory Enables the memory metrics module (saved allocation estimation). (default: true)/pulse config metricsModuleWriteQueue Enables the write queue metrics module (event loop task savings tracking). (default: true)
Permission Nodes
PulseNet uses the Fabric Permissions API for command permissions. Each node has a fallback vanilla permission level for servers without a permissions mod.
General
| Node |
Default |
Description |
pulsenet.pulse |
ALL |
Access the /pulse base command (shows version) |
pulsenet.reload |
GAMEMASTERS |
Reload the PulseNet config file |
pulsenet.netstats |
GAMEMASTERS |
View network, CPU, and memory statistics |
pulsenet.netstats.bar |
GAMEMASTERS |
Toggle the metrics boss bar overlay |
pulsenet.netstats.reset |
GAMEMASTERS |
Reset all metrics counters to zero |
pulsenet.packetnames |
GAMEMASTERS |
List observed packet class names and channel IDs |
Config
Config commands are generated dynamically per config value. The <name> below corresponds to the camelCase config key (e.g. batchingEnabled, metricsUpdateInterval).
| Node |
Default |
Description |
pulsenet.config |
GAMEMASTERS |
List all config values |
pulsenet.config.<name>.get |
GAMEMASTERS |
Read a specific config value |
pulsenet.config.<name>.set |
GAMEMASTERS |
Change a specific config value |
Try My Other Mods!
All server-side Fabric mods — no client installation required.
|
Mod |
Description |
Links |
 |
Arcana Novum |
Minecraft's biggest server-only full-feature Magic Mod! Adds powerful items, multiblocks and bosses! |
   |
 |
Ancestral Archetypes |
A highly configurable, Origins-style mod that lets players pick a mob to gain unique abilities! |
|
 |
Ender Nexus |
Highly configurable /home, /spawn, /warp, /tpa and /rtp commands all in one, and individually disablable. |
|
 |
Fabric Mail |
An in-game virtual mailbox system for sending packages and messages between online and offline players. |
|
 |
Fabric Trade |
Adds /trade, a secure player-to-player trading interface. |
|
 |
Limited AFK |
AFK detection and management with configurable kick thresholds for servers. |
|
 |
Links in Chat |
Makes URLs posted in chat clickable. |
|
Support and Contributions
PulseNet is an open-source project by PulseMC. We welcome contributions regarding Netty, Mixin, and protocol-level optimizations.
PulseNet: The Heartbeat of High-Performance Networking.
