CLion Help

Tuning CLion

In this section:

Increasing productivity

To increase productivity of CLion, you can change settings that reside in the following locations (depending on your operating system) :

  • On Windows systems:
    <CLion installation folder>/bin/clion64.exe.vmoptions
  • On *NIX systems:
    <CLion installation folder>/bin/clion64.vmoptions
  • On OS X: The file /Applications/ should be copied to ~/Library/Preferences/clionXX/clion.vmoptions

Alternative ways for Windows and Linux platforms

CLion makes it possible to increase productivity without editing files in the CLion installation folder.

This is done in one of the two ways:

  • Specify CL_VM_OPTIONS environment variable. This variable should contain the path to the file with the settings.
  • Create $HOME/.clionXX/idea$BITS.vmoptions (for *NIX) or %USERPROFILE%\.clionXX\clion%BITS%.exe.vmoptions (for Windows) respectively.

    The value of the variable BITS:

    • For 32-bit systems it is empty.
    • For 64-bit systems it is 64.

    Finally, you have to create:

    For *NIX 32-bit: $HOME/.clionXX/clion.vmoptions

    For *NIX 64-bit: $HOME/.clionXX/clion64.vmoptions

    For Windows 32-bit: %USERPROFILE%\.clionXX\clion.exe.vmoptions

    For Windows 64-bit: %USERPROFILE%\.clionXX\clion64.exe.vmoptions

If CL_VM_OPTIONS environment variable is defined, or the file $HOME/.clionXX/idea$BITS.vmoptions (for *NIX) or %USERPROFILE%\.clionXX\clion%BITS%.exe.vmoptions (for Windows) exists, then this file is used instead of the file located in the CLion installation folder.

Thus, to avoid editing files in the CLion installation folder, one should:

  1. Do one of the following:
    • Copy <CLion installation folder>/bin/clionXX.vmoptions to $HOME/.clionXX/clion$BITS.vmoptions (for *NIX) or %USERPROFILE%\.clionXX\clion%BITS%.exe.vmoptions (for Windows)
    • Copy <CLion installation folder>/bin/clionXX.vmoptions somewhere and save the path to this location into the environment variable CL_VM_OPTIONS
  2. Edit the file in the new location.

Increasing heap size

To increase CLion heap size, you should copy the original clion.vmoptions file from the /Applications/ to ~/Library/Preferences/clionXX/clion.vmoptions, then modify the -Xmx setting.

Managing case of unicode literals

CLion allows defining whether non-ascii characters should use literals like '\u00AB' or '\00ab'.

This behavior is controlled by the system property idea.native2ascii.lowercase. By default, upper case characters are used.

If it is desirable to use lower case characters, do the following (depending on your platform) :

  • On Windows and *NIX: add the line

    to the bin/ file, located under the product installation.

  • On OS X:

    Copy the file /Applications/ to ~/Library/Preferences/clionXX/, open it for editing, and add the line


    It is essential to create a copy, since the settings are replaced rather than added.

See Also

Last modified: 20 October 2015