The UV 1000 is a large shared memory machine. Our single machine is still housed in the HLRN where it was used from 2011 to 2013 by the previous owners.
Although the UV can be used as any other multi core machine to run shared memory programs it does not behave in the same way as your standard office computer. This is a result of the much larger scale and fundamentally different architecture to reach these proportions.
The most important fact to remember: location, location, location! The UV is a small cluster in itself and does in fact have a internal network to handle memory sharing using a proprietary interconnect called NUMAlink. This interconnect is used to create a network between all blades using switches, just as your typical InfiniBand or Ethernet fabric.
Slides Covering NUMA locality using the UV 1000 as example:
http://www.ncsa.illinois.edu/Conferences/IWOMP11/program/presentations/schmidl.pdf