Trouble-shooting


A collection of trouble-shooting steps.

  1. Java Heap Problem

    When loading or saving large XML files, MATLAB sometimes reports problems due to insufficient heap memory for the Java Virtual Machine.
    You can increase the heap space for the Java VM in MATLAB 6.0 and higher by creating a java.opts file in the $MATLAB/bin/$ARCH (or in the current directory when you start MATLAB) containing the following command:

    -Xmx$MEMSIZE

    Recommended:

    -Xmx536870912

    which is 512Mb of heap memory.

    An additional workaround reported in case the above doesn't work: It sometimes happens with MATLAB R2007b on WinXP that after you create the java.opts file, MATLAB won't start (it crashes after the splash-screen).
    The workaround is to set an environment variable MATLAB_RESERVE_LO=0.

    This can be set by performing the following steps:

    1. Select Start->Settings->Control Panel->System
    2. Select the "Advanced" tab
    3. On the bottom, center, click on "Environment variables"
    4. Click "New" (choose the one under "User variables for Current User")
    5. Enter
      Variable Name: MATLAB_RESERVE_LO
      Variable Value: 0
    6. Click OK as many times as needed to close the window


    Then edit/create the java.opts file as described above. You can also specify the units (for instance -Xmx512m or -Xmx524288k or -Xmx536870912 will all give you 512 Mb).




©LTP Team