This chapter describes the function and physical components of the NUMAlink module in the following sections:
The NUMAlink module is a high-speed switch that routes network packets between compute modules, MPX modules, and PCI expansion modules. The NUMAlink module consists of eight ports. Four ports can connect to compute modules and/or MPX modules. The other four ports, which carry USB signals, can connect to compute modules, MPX modules, and/or PCI expansion modules.
 | Note: The USB signals enable the compute modules, MPX modules, and PCI expansion modules to communicate with the L2 controller. The compute modules and/or MPX modules that connect to the four ports that do not carry USB signals communicate with the L2 controller directly or via a USB hub. |
The NUMAlink module has the following features:
SGI custom-designed router ASIC, which is an eight-port crossbar that connects any input-link channel to any of the seven possible output-link channels (see Figure 5-1). The NUMAlink channels operate at 1.6 GB/s (each direction).
USB port for system controller support.
L1 controller and LCD display.
Two hot-pluggable cooling fans.
This section describes the external components on the front and rear panels of the NUMAlink module.
The NUMAlink module contains the following front panel items (see Figure 5-2):
L1 display. The L1 display is a 55.7 mm x 32 mm backlit liquid crystal display (LCD) that displays system messages. It displays two lines with a maximum of 12 characters on each line.
Note: See the SGI L1 and L2 Controller Software User's Guide (007-3938-00x) for more information about the L1 controller. On/Off switch with LED. Press this button to turn on the NUMAlink module internal components. You can also turn on the NUMAlink module internal components at a system console.
Three LEDs:
On/Off switch LED. This LED illuminates green when the NUMAlink module internal components are on and turns off when they are off.
Service-required LED. This LED illuminates orange to indicate that an item is broken or not operating properly (for example, a fan is off), but the NUMAlink module is still operating.
Failure LED. This LED illuminates red to indicate that a system failure has occurred and the NUMAlink module is down.
Fans. Two hot-pluggable fans provide N+1 redundant cooling.
The NUMAlink module has the following rear panel items (see Figure 5-3):
Power connector. This connector connects the NUMAlink module to a power distribution unit or power strip via a power cable.
LINKS R TO R connectors (1, 6, 7, and 8, or A, F, G, and H). These link connectors connect the NUMAlink module to compute modules and/or MPX modules.
LINKS R TO R and C TO R connectors (2, 3, 4, and 5, or B, C, D, and E). These link connectors connect the NUMAlink module to compute modules, MPX modules, and/or PCI expansion modules.
Link connector LEDs. Each link connector has two LEDs, as follows:
The yellow LED illuminates to indicate that both the NUMAlink module and the module to which it is connected are powered on.
The green LED illuminates when a link has been established between the NUMAlink module and the module to which it is connected.
L1 port connector. This connector connects the internal USB hub of the NUMAlink module to the L2 controller. The internal USB hub receives the USB signals from the L2 controller via this port and distributes these signals to the following components:
Table 5-1 lists the technical specifications of the NUMAlink module.
Table 5-1. NUMAlink Module Technical Specifications
Characteristic | Specification |
|---|---|
Height | 3.3 in. (83.82 mm) |
Width | 17.38 in. (441.45 mm) |
Depth | 27.5 in. (698.50 mm) |
Weight | 20 lb (9.1 kg) |
Input power | 110/220 VAC (~ 60 W) |
Table 5-2 lists the specifications of the NUMAlink module ports.
Table 5-2. NUMAlink Module Port Specifications
Port | Quantity | Peak Transfer Rate |
|---|---|---|
Link | 8 | 1.6 GB/s each direction |
L1 | 1 | 12 Mbits/s |
Table 5-3 lists the bandwidth characteristics of the NUMAlink module.
Table 5-3. Bandwidth Characteristics of the NUMAlink Module
Characteristic | Peak Bandwidth | Sustainable Bandwidth |
|---|---|---|
NUMAlink channel | 3.2 GB/s full duplex 1.6 GB/s each direction | ~1420 MB/s each direction |