eclipse.ini vm arguments - eclipse.ini File Location Mac, Windows

eclipse.ini is the configuration file used to control the Eclipse startup. We can configure Eclipse VM arguments such as JDK to be used (eclipse.ini vm), permgen space, maximum and minimum heap size using Xms, Xmx parameters.

eclipe.ini File Location

For windows, it’s in the same directory as eclipse.exe file, as shown in below image. For Mac OS X, it’s found inside the app. So if Eclipse app is in Downloads directory, eclipse.ini file location will be:

pankaj$ cd ~/Downloads/Eclipse.app/Contents/Eclipse/

You can reach this location by first right clicking on Eclipse app and click on “Show Package Contents” and then in the next window navigate to Contents/Eclipse directory, as shown in below images. Here is the example eclipse.ini file from my default eclipse installation.

-startup
../Eclipse/plugins/org.eclipse.equinox.launcher_1.3.100.v20150511-1540.jar
--launcher.library
../Eclipse/plugins/org.eclipse.equinox.launcher.cocoa.macosx.x86_64_1.1.300.v20150602-1417
-product
org.eclipse.epp.package.jee.product
--launcher.defaultAction
openFile
-showsplash
org.eclipse.platform
--launcher.XXMaxPermSize
256m
--launcher.defaultAction
openFile
--launcher.appendVmargs
-vmargs
-Dosgi.requiredJavaVersion=1.7
-XstartOnFirstThread
-Dorg.eclipse.swt.internal.carbon.smallFonts
-XX:MaxPermSize=256m
-Xms256m
-Xmx1024m
-Xdock:icon=../Resources/Eclipse.icns
-XstartOnFirstThread
-Dorg.eclipse.swt.internal.carbon.smallFonts

Some important points about eclipse.ini file are:

1. Each line before -vmargs contains an option followed by the value for option.
2. All the lines after -vmargs are passed as JVM arguments, so all options and arguments for eclipse startup must be specified before -vmargs. For example -vm settings for JDK to be used.
3. --launcher.XXMaxPermSize specifies the maximum permgen space to use by eclipse launcher, increase this value if your eclipse startup is failing with out of memory error.
4. If you are getting Out of Memory errors, you should try to increase Permgen space and maximum heap space values. They are configured using VM arguments -XX:MaxPermSize, -Xms and -Xmx. Permgen space default value is configured as 256MB that is good for small to medium projects.

eclipse.ini vm argument

eclipse.ini vm argument is useful when you have multiple JDK installation and you want to make sure that your eclipse runs on a specific JVM, rather than picking system configured jdk path. It must be defined before -vmargs.

eclipse.ini vm argument Mac

My eclipse.ini file snippet showing -vm argument usage to configure eclipse to use JDK8 in Mac OS X.

-vm
/Library/Java/JavaVirtualMachines/jdk1.8.0_73.jdk/Contents/Home/bin
-vmargs

You can configure it similarly for Windows or Linux operating systems. Just change the JDK bin directory path accordingly.

eclipse.ini Permgen Space

If you are getting java.lang.OutOfMemoryError: PermGen space error, mostly when you are working on larger code base, doing maven update for large projects etc. , then you should increase Permgen space. Below is the configuration to increase permgen space to 512 MB in eclipse.ini file.

-XX:MaxPermSize=512M

Note that there is no more Permgen space from Java 8 onwards, so setting this option will have no effect. However you will also not get out of memory error because of permgen space.

eclipse.ini Heap Space

If you are getting OutOfMemoryError related to Heap space, then you can try to increase the maximum heap size available to eclipse. You can easily do it by editing -Xmx value. For example, below snippet will increase the eclipse heap size to 2 GB.

-Xmx2048m

That’s all for a quick roundup on eclipse.ini configuration and VM arguments.