HP Scalable Visualization Array Software - Manual (Page 21)

images. The output can be a complete display or one tile
of an aggregate display.
Remote images. The SVA also supports the transmission of a complete
image to a system external to the cluster over an external
network for remote viewing; for example, to an office
workstation outside the lab. A node with a port connected
to the external network is recommended. Alternatively,
you can connect to the external network by routing through
another cluster node with such a port.
Integrate an application user
interface. An application user interface (UI) usually runs on a cluster
node. The UI typically controls the parts of the distributed
application running on other nodes. A node that provides
users with access to the UI can have an attached keyboard,
mouse, and monitor for user interaction. Alternatively, the
node can export the application UI to an external node
using the X protocol or using the HP Remote Graphics
Software (RGS) or VirtualGL. If you use RGS or VirtualGL,
a port connected to the external network is recommended.
2.2.3 Components of an SVA
The main tasks described in Section 2.2.2 are supported by two types of visualization nodes,
which differ in their configuration and in the tasks they carry out. The two nodes types can carry
out multiple tasks. These node types are unique to the SVA configuration and extend HP compute
clusters to support visualization functions. See
Chapter 3 for detailed information on the hardware
configurations of these node types.
Display Nodes Display nodes carry out the display task. Typically, a display node contains
one or two graphics cards, each connected to its display device(s). The
output of each graphics card port (two ports per card) on a display node
can be sent to a display device. Final output can be a single tile or a partial
image in the form of a single tile, which is part of an aggregate multi-tile
display.
The SVA supports up to eight display nodes in a Display Surface. The
display nodes in your cluster can drive one or two display devices in the
case of the xw8200, xw8400, DL140 G3, and DL145 G3 nodes, and one to
four display devices in the case of xw9300 and xw9400 nodes. See the SVA
System Administration Guide for more information on setting up display
nodes, displays, and Display Surfaces.
Render Nodes Render nodes render images, as do display nodes. However, render nodes
are not connected directly to display devices. Typically, render nodes are
used by visualization applications that composite images. Render nodes
render a part of the final image. These sub-images are combined with
sub-images from other nodes. The composited image data is transferred
to another render node, or to a display node to be routed to a display device.
Render nodes are industry standard workstations or servers with standard
OpenGL 3D graphics cards.
Both types of nodes can perform UI and remote graphics functions. When nodes are allocated
to a job, the job typically requires specific display nodes that correspond to the display devices
intended for use. Typically, there is no requirement for specific render nodes.
2.2.4 Configuration Flexibility
The SVA supports several different configurations and uses. These include:
2.2 Architectural Design 21