How to check disk usage?

Morning everyone!

So we have a vApp installation of vROPS 6.0.1 in our environment. It was previously running very sluggishly due to being sized smaller than it should have been, so I upped the CPU, memory, and disk space and now it's running great.

However, I'd like to know the disk usage to see if that was the bottleneck. How do I do that through either UI interface (regular or admin) or by remoting into the vApp?

Thanks!