Eclipse headless build OutOfMemoryError

Question

I am running headless eclipse to execute JUnit tests

My command looks like this:

"C:\Program Files (x86)\Java\jdk1.6.0_45\jre\bin\java.exe"  
-cp "C:\eclipse-jee-kepler-SR2-win32\eclipse\plugins\org.eclipse.equinox.launcher_1.3.0.v20130327-1440.jar" 
org.eclipse.equinox.launcher.Main 
-noupdate 
-application org.eclipse.ant.core.antRunner 
-data "C:\Users\US\.jenkins\workspace\XBTests\ecworkspace" 
-buildfile "C:\Users\US\.jenkins\workspace\XBTests\testrunscripts\runtests.xml" 

The tests are running as expected, and everything was going good.

Then one day I got

java.lang.OutOfMemoryError: Java heap space

My question is that to increase memory, in the command above, I should add:

1. -vmargs -Xmx1024M
2. Or just -Xmx1024M

Answer 1

Verified that passing -vmargs -Xmx1024M will not increase memory of the executed java.exe.

Removing -vmargs resolved the OutOfMemoryError problem.

Hence answer to my question is 2.