How to fix IntelliJ OutOfMemoryError

If you have a large project, you might get this error when trying to do a full build

Error:java: OutOfMemoryError: insufficient memory

You can fix this by increase memory in two places in the IDE. For example, let says you want to increase to 2GB of memory:

1. Update the idea64.exe.vmoptions file with -Xmx2048m to increase Java max heap memory size for your IDE. (Require IDE restart)

2. Go to IDE menu: File > Settings … > Build, Execution, Deployment > Compiler > "Build process heap size (Mbytes):" and increase it to 2000.