16 Java Management
Daniel Scalzi edited this page 2019-09-06 03:13:56 -04:00

aventium softworks

Java Management

Customize your Java executable, allocate more RAM, or experiment with JVM args.

Java Settings

Java Management Tab. Accessible in the settings menu.


The launcher was designed to handle Java setup for you. If you're an advanced user or would like to simply tinker with the default settings, you may do so on the Java Management Tab.


The Launcher Handles Everything for You

The launcher validates the configured Java executable before each launch. If the configured value does not point to a valid Java version, your computer will be scanned for a valid version. If you do not have a valid installation, the game will not launch. WesterosCraft requires Java 8 x64 greater than update 52.

Why is Java 10+ not supported? Forge and LaunchWrapper only support Java 8.

Automatically Install a Valid Version of Java

The launcher will give you the option to automatically download a valid version of Java if it fails to find one. It will download it to .westeroscraft/runtime/x64 as a local installation (only for the launcher). We recommend using this option.

Automatic Java Install

Manually Installing a Valid Version of Java

If you want to manually install Java rather than having the launcher do it for you, follow these steps.

  • Download Java 8 x64
    • Windows/macOS
      • Download from Oracle.
      • For Windows: Windows x64 (jre-8uVERSION-windows-x64.exe)
      • For macOS: Mac OS X x64 (jre-8uVERSION-macosx-x64.dmg)
    • Linux:
      • OpenJDK (recommended): $ sudo apt-get install openjdk-8-jre
      • Oracle: Instructions
  • Follow on-screen instructions.
  • Try to launch the game again, the launcher should find the version you just installed. If it does not, try setting the value manually.
Manual Java Install

Java Management Tab

Change Minimum or Maximum RAM

Allocating RAM is easy! Just move the sliders to your desired value. You can set the value to the nearest half a gigabyte.

RAM Sliders

Technical Notes

  • WesterosCraft requires 3GB of RAM to run smoothly.
  • We recommend setting the miminum and maximum to the same value.
    • Having the JVM expand and contract the heap while chasing the 'free to used ratio' that it targets can be expensive and generate and cause random lag spikes.
  • Avoid allocating more than 1/2 your total RAM unless you know what you're doing.
  • The slider will change color based on how much RAM you allocate.
    • Green: Less than 1/4 of your total available RAM.
    • Yellow: Greater than 1/4 of your total available RAM.
    • Red: Greater than 1/2 of your total available RAM.
  • The minimum amount you can allocate is determined by the following.
    • Total RAM < 6GB : 2G
    • Total RAM ≥ 6GB : 3G
  • The maximum amount you can allocate is determined by the following.
    • Total RAM ≤ 16GB : (Total RAM) - (1GB for OS) - (1GB per each 4GB of RAM)
    • Total RAM > 16GB : (Total RAM) - (1GB for OS) - (1GB for each 8GB of RAM > 16GB) - (1GB per each 4GB of RAM)

Change the Java Executable

  • Click Choose File.
  • Navigate to the JRE/JDK you wish to use.
  • Select the executable.
    • Windows: bin\javaw.exe
    • macOS/Linux: bin/java
Java Executable

Modify JVM Arguments

Advanced use only. Do not specify -Xmx or -Xms here. These values are modified by the memory sliders.

JVM Arguments

Available Arguments:


Releated Release Notes