We were getting the following intermittent error on our builds:

FATAL: /var/lib/jenkins/xvfb-157-8380869945976165128.fbdir/.nfs00000000000ad5a20004f107: Device or resource busy
java.nio.file.FileSystemException: /var/lib/jenkins/xvfb-157-8380869945976165128.fbdir/.nfs00000000000ad5a20004f107: Device or resource busy
at sun.nio.fs.UnixException.translateToIOException(UnixException.java:91)

In order to address this, I started passing the following flag: "-fbdir /tmp"
See attached screen shot.

The error seems to have gone away, but in the console log, I see that the -fbdir flag is being passed twice. Does Xvfb ignore the first -fbdir parameter and only read the 2nd one?

Here is the new message in the console log:
Xvfb starting$ /usr/bin//Xvfb -displayfd 2 -screen 0 1024x768x24 -fbdir /var/lib/jenkins/xvfb-381-8251290578769946893.fbdir -fbdir /tmp