How to modify Java Heap Size on AhsayACB

September 12, 2025

Article ID

5008

Last Reviewed Date

Product Version

AhsayACB / AhsayOBM: 8 or above

Operating System

All Platforms

Description

This Know-How article outlines the steps required to modify the Java heap size of AhsayOBM / AhsayACB.

Solution

To modify the Java heap size of AhsayOBM installation on Windows / macOS, Linux or NAS, you need to amend the following files:

For Windows:

  • ${AhsayOBM-Install-Home}\config.ini
  • ${AhsayOBM-Install-Home}\bin\RunCB.bat

For macOS:

  • ${AhsayOBM-Install-Home}/config.ini
  • ${AhsayOBM-Install-Home}/bin/RunCB.sh

For Linux:

  • ${AhsayOBM-Install-Home}/config.ini
  • ${AhsayOBM-Install-Home}/bin/RunCB.sh
  • ${AhsayOBM-Install-Home}/bin/RunBackupSet.sh

For NAS:

  • Synology: ${AhsayOBM-Install-Home}/get-suitable-xmx.sh
  • QNAP: ${AhsayOBM-Install-Home}/get-suitable-xmx.sh

The default location for the get-suitable-xmx.sh:

  • Synology: /volume1/@appstore/AhsayOBM/obm/util/bin/get-suitable-xmx.sh
  • QNAP: /share/CACHEDEV1_DATA/.qpkg/AhsayOBM/obm/util/bin/get-suitable-xmx.sh

Follow the steps below:

  1. For Windows, open the 'config.ini' and 'RunCB.bat' files with a text editor.

    config.ini
    app.system.ui.vm.opt.xms=128
    app.system.ui.vm.opt.xmx=2048
    app.system.conf.language=en
    RunCB.bat
    ...
    SET PATH=%JAVA_HOME%\bin;%PATH%
    ...
    SET JAVA_OPTS=-Xms128m -Xmx2048m -XX:MaxDirectMemorySize=1024m ...
    ...

    For macOS, open the 'config.ini' and 'RunCB.sh' files with a text editor.

    config.ini
    app.system.ui.vm.opt.xms=128
    app.system.ui.vm.opt.xmx=2048
    app.system.conf.language=en
    RunCB.sh
    ...
    JAVA_OPTS="Xrs -Xms128m -Xmx2048m -client"
    JNI_PATH="-Djava.library.path=$LIB_HOME"
    ...

    For Linux, open the 'config.ini', 'RunCB.sh' and 'RunBackupSet.sh' files with a text editor.

    config.ini
    app.system.ui.vm.opt.xms=128
    app.system.ui.vm.opt.xmx=2048
    app.system.conf.language=en
    RunCB.sh / RunBackupSet.sh
    ...
    JAVA_OPTS="Xrs -Xms128m -Xmx2048m -client"
    JNI_PATH="-Djava.library.path=$LIB_HOME"
    ...

    For NAS, open the 'get-suitable-xmx.sh' file with a text editor.

    get-suitable-xmx.sh
    # User defined java heap max in unit of MB
    JAVA_HEAP_MAX_IN_MB=2048
    JAVA_HEAP_MIN_IN_MB=64
    The value 2048, in the above examples are the current Java heap size (in MB).

  2. Amend the following line by changing the value to '4096' (value in MB) (depending on the amount of free system memory available):

    • In config.ini amend app.system.ui.vm.opt.xmx=2048

    • In RunCB.bat amend SET JAVA_OPTS=-Xms128m -Xmx2048m -XX:MaxDirectMemorySize=1024m ...

    • In RunCB.sh amend JAVA_OPTS="-Xrs -Xms128m -Xmx2048m -client"
    • In RunBackupSet.sh amend JAVA_OPTS="-Xrs -Xms128m -Xmx2048m -client"
    • In get-suitable-xmx.sh amend JAVA_HEAP_MAX_IN_MB=4096

    For Windows:

    config.ini (Updated)
    app.system.ui.vm.opt.xms=128
    app.system.ui.vm.opt.xmx=4096
    app.system.conf.language=en
    RunCB.bat (Updated)
    ...
    SET PATH=%JAVA_HOME%\bin;%PATH%
    ...
    SET JAVA_OPTS=-Xms128m -Xmx4096m -XX:MaxDirectMemorySize=1024m ...
    ...

    For macOS:

    config.ini (Updated)
    app.system.ui.vm.opt.xms=128
    app.system.ui.vm.opt.xmx=4096
    app.system.conf.language=en
    RunCB.sh (Updated)
    ...
    JAVA_OPTS="Xrs -Xms128m -Xmx4096m -client"
    JNI_PATH="-Djava.library.path=$LIB_HOME"
    ...

    For Linux:

    config.ini (Updated)
    app.system.ui.vm.opt.xms=128
    app.system.ui.vm.opt.xmx=4096
    app.system.conf.language=en
    RunCB.sh / RunBackupSet.sh (Updated)
    ...
    JAVA_OPTS="Xrs -Xms128m -Xmx4096m -client"
    JNI_PATH="-Djava.library.path=$LIB_HOME"
    ...

    For NAS:

    get-suitable-xmx.sh (Updated)
    # User defined java heap max in unit of MB
    JAVA_HEAP_MAX_IN_MB=4096
    JAVA_HEAP_MIN_IN_MB=64
  3. Save the changes, then restart the scheduler service.
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