HP's Superdome

A server based on the Superdome architecture, which uses the PA-8800 RISC processor, can scale up to 128 such processors. This architecture uses two CPU cores on a single chip, each with 32 MB of L2 cache. This allows higher processor density in the server, improving the performance. The architecture can also be used with Intel?s Itanium processor.

The server chipset, HP sx1000, is designed to support both the processors. ?

The building block of the Superdome architecture is the cell board. It?s a complete server unit in itself, comprising the processor, memory, main controller and all other necessary hardware. The controller is the center of the cell board, and it connects the memory, processors, I/O and crossbar. Each cell board can take up to four CPU boards (each having two CPU cores) and supports up to 64 GB of memory. The memory is divided into four sub-systems, with each CPU board having 16 GB of memory. The peak memory bandwidth offered is 16 GB per sec per sub-system. There?s a dedicated channel between the controller and two CPU boards. The overall bandwidth offered for these CPU boards is 12.8 GB per sec. The controller connects to 12 PCI-X slots, out of which eight are regular ones offering 533 MB per sec bandwidth and four are 1066 MB per sec (high-bandwidth) slots. The crossbar connects to the cell boards with each other. ?

The highest end of Superdome servers offer peak memory bandwidths of 256 GB per sec

There are three different configurations for the Superdome based on these cell boards. These include 32, 64 and 128-way servers. The 32-way machine would have up to four cell boards and 64 would have eight cell boards. The peak crossbar bandwidth for the three servers is between 16 to 64 GB per sec. The cell boards have been made in such a way that they?re very easy to add or remove from the server. So, if your Superdome is using the earlier PA-RISC processors, such as the PA-8600 or 8700, then switching over to PA-8800 is just a matter of swapping the cell boards. ?

Having looked into the basic system architecture, it?s easy to do the maths and figure out the capabilities of the various Superdome servers. So, the 32-way machine supports memory ranging from 256 GB, while the 128-way machine can take up to 1 TB of memory. ?

Similarly, the 128-way machine can support up to 192 PCI-X slots. ?

Each server can be partitioned in three ways, which are hard, virtual and resource. Hard partitioning is to physically pull out the cell boards you don?t want to use. Virtual partition creates separate isolated OS instances on the same system. The resource partition runs within a virtual or hard partition, but can dynamically allocate resources from within the virtual partition for the application that requires it. ?

64-way Superdome at amazon.com?

The most commonly known e-commerce site, amazon.com, uses two HP Superdome 64-way servers to host its data warehouse and handle the high volume of transactions. This data warehouse maintains the order, customer and inventory data. It's accessible to almost every system in the organization. It's a challenge to manage the continuously increasing size of the data warehouse, respond to dealers, customer queries and process transaction in lesser time.