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Iris provides three different pregeneration systems, each optimized for different use cases. Choose the system that best fits your needs.

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Standard Pregeneration

The standard /pregen command provides GUI-based pregeneration with progress tracking.

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Start Pregeneration

/pregen start <radius> [world] [center] [gui]
Parameters:
  • radius - Radius in blocks (minimum: 1024)
  • world - World to pregenerate (defaults to current world)
  • center - Center point (default: 0,0, use me for your location)
  • gui - Show progress GUI (default: true)
Aliases: pregenerate Example: 
/pregen start 5000
/pregen start 10000 MyWorld center=me
/pregen start 3000 TestWorld center=0,0 gui=false

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Stop Pregeneration

Stop the active pregeneration task. 
/pregen stop
Aliases: x

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Pause/Resume Pregeneration

Toggle pause state of active pregeneration. 
/pregen pause
Aliases: t, resume, unpause

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Lazy Pregeneration

Lazy pregen runs in the background with configurable rate limiting, perfect for pregeneration during server runtime.

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Start Lazy Pregen

/lazypregen start <radius> [world] [center] [maxcpm] [silent]
Parameters:
  • radius - Radius in blocks to pregenerate
  • world - World to pregenerate (defaults to current)
  • center - Center location (default: 0,0)
  • maxcpm - Maximum chunks per minute (default: 999999999)
  • silent - Disable status messages (default: false)
Aliases: lazy Example: 
/lazypregen start 10000
/lazypregen start 5000 MyWorld maxcpm=1000
/lazypregen start 3000 TestWorld center=me maxcpm=500 silent=true
Lazy pregen is designed to run continuously in the background. The maxcpm parameter prevents server lag by limiting generation speed.

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Stop Lazy Pregen

Stop lazy pregeneration for a world. 
/lazypregen stop <world>
Aliases: x Example: 
/lazypregen stop MyWorld

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Pause/Resume Lazy Pregen

Toggle pause state of lazy pregeneration. 
/lazypregen pause <world>
Aliases: t, resume, unpause Example: 
/lazypregen pause MyWorld

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Turbo Pregeneration

Turbo pregen is optimized for maximum speed, ideal for pregenerating worlds before server launch.
Turbo pregen uses maximum system resources and should only be used when the server is not accepting players.

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Start Turbo Pregen

/turbopregen start <radius> [world] [center]
Parameters:
  • radius - Radius in blocks to pregenerate
  • world - World to pregenerate (defaults to current)
  • center - Center location (default: 0,0)
Aliases: turbo Example: 
/turbopregen start 20000
/turbopregen start 15000 MyWorld center=0,0

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Stop Turbo Pregen

Stop turbo pregeneration for a world. 
/turbopregen stop <world>
Aliases: x Example: 
/turbopregen stop MyWorld

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Pause/Resume Turbo Pregen

Toggle pause state of turbo pregeneration. 
/turbopregen pause <world>
Aliases: t, resume, unpause Example: 
/turbopregen pause MyWorld

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Choosing the Right Method

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Standard Pregen (/pregen)

Best for:
  • Visual progress tracking
  • Moderate-sized pregeneration
  • Interactive monitoring
Advantages:
  • GUI with detailed progress
  • Balanced performance
  • Easy to monitor

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Lazy Pregen (/lazypregen)

Best for:
  • Background pregeneration during gameplay
  • Gradual world expansion
  • Rate-limited generation
Advantages:
  • Runs alongside players
  • Configurable speed limits
  • Persistent across restarts
  • Minimal lag impact

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Turbo Pregen (/turbopregen)

Best for:
  • Pre-launch world preparation
  • Maximum speed generation
  • Server downtime windows
Advantages:
  • Fastest generation speed
  • Maximum resource utilization
  • Best for large areas
Disadvantages:
  • High system resource usage
  • Not suitable during gameplay

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Best Practices

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Before Starting

  1. Backup your world - Always create backups before pregeneration
  2. Check disk space - Ensure sufficient storage for the generated chunks
  3. Test first - Run a small radius test before large-scale pregeneration

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During Pregeneration

  1. Monitor performance - Watch server TPS and resource usage
  2. Adjust rates - For lazy pregen, tune maxcpm based on server performance
  3. Plan restarts - Standard and turbo pregen resume automatically, lazy pregen saves state

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Estimating Size

A rough estimate for world size:
  • Radius 1000 blocks: ~10-50 MB
  • Radius 5000 blocks: ~100-500 MB
  • Radius 10000 blocks: ~500 MB - 2 GB
  • Radius 20000 blocks: ~2-8 GB
Actual sizes vary greatly depending on dimension complexity, structures, and terrain features.

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Monitoring Progress

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GUI Progress (Standard Pregen)

The GUI shows:
  • Percentage complete
  • Chunks generated
  • Estimated time remaining
  • Current generation speed

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Console Messages (All Methods)

All methods log progress to console: 
[Iris] Pregeneration 45% complete (9000/20000 chunks)
[Iris] Current speed: 150 chunks/minute

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Files Created

  • Lazy: lazygen.json in world folder
  • Turbo: turbogen.json in world folder

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Permission Nodes

iris.command.pregen.start
iris.command.pregen.stop
iris.command.pregen.pause
iris.command.lazypregen.start
iris.command.lazypregen.stop  
iris.command.lazypregen.pause
iris.command.turbopregen.start
iris.command.turbopregen.stop
iris.command.turbopregen.pause

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