2.5. Hardware Models
A Cray X1 system is available as either an air-cooled (AC) or a liquid-cooled (LC) model.
Both models are multicabinet systems that include one or more of the following cabinets: mainframe cabinet (MFC), I/O cabinet (IOC), and peripheral cabinet (PC-20). The mainframe cabinets differ between the model types. Both models use the same IOC and PC-20 cabinets. IOCs and PC-20s are always air cooled. The following subsections describe the two models in more detail.
2.5.1. Air-cooled Model
A Cray X1 air-cooled system requires a minimum of one MFC-AC mainframe cabinet, one IOC, and one PC-20. Additional peripheral cabinets can be added, depending on the system configuration. All cabinets are air cooled; the system does not use facility water for cooling. Air-cooled systems do not require a raised computer room floor, but a raised floor is recommended.
Figure 2-5 shows a Cray X1 air-cooled system with one MFC-AC mainframe cabinet, one IOC, and two PC-20s.
The MFC-AC and IOC are physically attached to each other; cabling between the MFC-AC and IOCs is run through cable troughs at the top of the system. PC-20s do not use cable troughs; cabling between an IOC and PC-20s is typically run under the raised computer room floor.
An MFC-AC cabinet holds up to 4 nodes (8-16 MSPs) and their associated routers. A two MFC-AC air-cooled system will be available in early 2004, yielding systems that range from 2 to 8 nodes (8 to 32 MSPs). Based on customer demand, multicabinet systems of up to four MFC-ACs may be available in the future, yielding systems that range from 2 to 16 nodes (8 to 64 MSPs).
An IOC houses I/O drawers (IODs) that provide a bridge between the MFC-AC and its various peripheral devices and the SAN. The MFC-AC communicates with an IOD using the SPC protocol. An IOD communicates with the Cray X1 system's various peripheral devices through Fibre Channel protocol. The Fibre Channels connect to/from the RAID disk storage, the CPES, and CNSs. Fibre Channel HBAs in a Cray X1 I/O drawer connect the Cray X1 hardware to the SAN.
Each Cray X1 air-cooled system requires a minimum of one IOD in the IOC. The number of drawers is dependent on the system's mainframe and peripheral configuration. An IOC can support up to 32 SPC mainframe connections and up to 128 Fibre Channel connections. For air-cooled systems with 4 nodes, the IOC uses up to 16 SPC mainframe connections and up to 64 Fibre Channel connections.
A PC-20 houses various peripherals, including the CPES, the CNS, and the RAID disk storage components. All Cray X1 air-cooled systems require a minimum of one PC-20 cabinet. Additional PC-20 cabinets are added based on the system's peripheral configuration.
2.5.2. Liquid-cooled Model
A Cray X1 liquid-cooled system requires a minimum of one MFC-LC mainframe cabinet, one IOC, and one PC-20. Additional cabinets can be added, depending on the system configuration. An MFC-LC requires facility water for cooling. IOCs and PC-20s are air-cooled. Cray X1 liquid-cooled systems require a raised computer room floor for routing the facility water.
Figure 2-6 shows a Cray X1 liquid-cooled system consisting of one MFC-LC, one IOC, and two PC-20s.
All MFC-LCs and IOCs are physically attached to each other; cabling between the MFC-LCs and IOCs is run through cable troughs at the top of the system. PC-20s do not use cable troughs; cabling between the IOC and PC-20s is typically run under the raised computer room floor.
Each MFC-LC holds up to 16 nodes and their associated routers. Cray X1 liquid-cooled systems can consist of 1 to 64 MFC-LC cabinets, yielding systems that range from 2 to 1024 nodes (8 to 4096 MSPs), with approximately 50 TFLOPS of aggregate computational power in its largest configuration.
An IOC houses I/O drawers (IODs) that provide a bridge between the MFC-LC and its various peripheral devices and the SAN. The MFC-LC communicates with an IOD using the SPC protocol. An IOD communicates with the Cray X1 system's various peripheral devices through Fibre Channel protocol. The Fibre Channels connect to/from the RAID disk storage, the CPES, and CNSs. Fibre Channel HBAs in a Cray X1 I/O drawer connect the Cray X1 hardware to the SAN.
Each Cray X1 liquid-cooled system requires a minimum of one IOC with two IODs. The number of cabinets and drawers is dependent on the system's mainframe and peripheral configuration. An IOC can support up to 32 SPC mainframe connections and up to 128 Fibre Channel connections.
A PC-20 houses various peripherals, including the CPES, the CNS, and the RAID disk storage components. All Cray X1 liquid-cooled systems require a minimum of one PC-20 cabinet. Additional PC-20 cabinets are added based on the system's peripheral configuration.