install gparted inside smartos Centos VM

Well. I'm not so virtuous to use parted inside a Centos VM to expand the filesystem.
By default the Centos Linux image dataset from SmartOS is large 10GB.
You can add another disk (it will be mounted in /data).
Or you can grow the ZFS volume related to disk0.

So, from the global zone grow the volume related to the Linux VM:

zfs set volsize=20G zones/<UUID>-disk0

I don't know, maybe you must stop the VM and start it again.

Now, from inside the VM, yes, you must install various rpms.
Firts of all the EPEL repository.

rpm --import https://fedoraproject.org/static/0608B895.txt
rpm -ivh https://dl.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm

yum install gparted
yum install xauth
yum install dejavu-lgc-sans-fonts.noarch

Now you can connect to the VM via ssh with the -X option (or -Y) and run gparted