Why does the exception "java.lang.OutOfMemoryError: Java heap space" keep appearing even after changing the -xmx VM option?

Question

I'm on a 64 bit OS on a Mac with 8GB of RAM. I need to allocate 2.9GB to some arrays of bytes in a program written in Java (I simply declare them). Since by default you can't use more than 1GB of heap space for running a java project, you need to specify in the VM options if your program needs more. I am on IntelliJ Idea, so I do this by going on Help -> Edit Custom VM Options and then changing the -xmx field. But no matter how many MBs I allocate, the program can't run due to this exception: Exception in thread "main" java.lang.OutOfMemoryError: Java heap space, as if I didn't change anything in the VM options. The PC has enough free RAM to contain arrays of 2.9GB when running the program.

Are you sure it isn't consuming more than 2.9GB? And what are you passing as the `-xmx` argument? — Carcigenicate, Aug 03 '19 at 15:41
Are you 100% sure about not allocate more than 2,9GB, one tip is know what type of data did you use, because for example int type allocates 4 bits — deon cagadoes, Aug 03 '19 at 15:46

score 1 · Accepted Answer · answered Aug 03 '19 at 16:14

1

Help -> Edit Custom VM Options is set for IDEA itself but not your program. Set -Xmx in Run -> Edit Configurations.. -> your application -> VM options instead.

answered Aug 03 '19 at 16:14

djzhu

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This solved it. – Mark Smith Aug 03 '19 at 16:20

Why does the exception "java.lang.OutOfMemoryError: Java heap space" keep appearing even after changing the -xmx VM option?

1 Answers1