HP Superdome


The HP Superdome is a high-end server computer developed and produced by Hewlett Packard Enterprise. The latest version of product, "Superdome 2" was introduced in 2010. Superdome 2 scales from 2 to 32 sockets and 4 TB of memory. When introduced in 2000, the Superdome used PA-RISC processors. Since 2002,
there has been another version of the machine based on Itanium 2 processors, marketed in parallel as the HP Integrity Superdome. The classic PA-RISC Superdome was subsequently rebranded to HP 9000 Superdome. The predecessor to the Superdome was the HP V-Class.
The HP Integrity Superdome 2 utilizes the Intel Itanium 93xx-series microprocessor, otherwise known as "Tukwila" and is totally redesigned with parts from the HP BladeSystem C7000 enclosure.
Since 2012 Intel Itanium 95xx microprocessor Poulson are available too. In 2017, Intel announced that their most recent Itanium chip would be their last Itanium update.
In 2016, Hewlett Packard Enterprise released the Superdome X, which is based on Intel Xeon processors.
Superdome usually runs the HP-UX operating system, although the Itanium 2 version is also compatible with many other systems, for example with Microsoft Windows Server 2008 R2, SUSE Linux Enterprise Server, Red Hat Enterprise Linux, Debian Squeeze, and OpenVMS V8.2-1.

Differences

The Superdome comes in four different generations :
A building block is a cell, a card holding 4 processors and memory. Superdome has a ccNUMA architecture, which means that processors have shorter access times for their cell's memory but longer access times for other cell's memories, and data items are allowed to be replicated across individual cache memories but are kept coherent with one another by cache coherence hardware mechanisms. In this case, a directory-based coherency mechanism is employed.
A center of each cell is an ASIC called cell controller, that connects to four processor sockets, to four local memory subsystems, and to the backplane. The CC itself contains a crossbar, and four CCs interconnect via a second-level crossbar. In maximum machine's configuration four second-level crossbars interconnect with each other, supporting in total 64 processor sockets.
Each socket may hold either a single-core PA-RISC processor, or a dual-core PA-RISC processor, a single-core Itanium 2 processor, two Itanium 2 processors, or one dual-core Itanium 2 processor. There are almost no architectural differences between PA-RISC and Itanium versions of Superdome.

Physical layout

Superdome is not mounted on a standard rack, it is instead shipped as either one or two dedicated cabinets. One cabinet scales up to 8 cells, two cabinets at most. They were supposed to be able to connect more than two cabinets, but never happened.

Input/output

Each CC connects to one local I/O controller, which in turn may connect at most to a single I/O card cage with 12 PCI-X slots. Maximum 192 slots are possible for the Legacy and SX1000. It is not possible to expand the number of I/O slots for a cell, so if a nPar needs more I/O slots needs to add another cell.
Superdome does not contain any internal hard disks, it relies exclusively on external disk enclosures.

Partitioning

Superdome supports nPars, that are granular on the level of a whole cell, this means that a maximum of 16 cells can be part of a nPar.
The Superdome also supports vPars, granular on a single core level and a single PCI slot level, this means that a top level nPar can house several vPars to better utilize the hardware in the Superdome.

Architecture (SX2000 version)

The architecture of the SX2000 is highly similar at first glance compared to the SX1000, however it has quite a few design differences.
Similarly to both Legacy and SX1000 setups, SX2000 can be:
The currently available options for SX3000 are:
For the SX3000 there are four integrated 10 Gbit ethernets per blade. In addition, maximum of 96 external PCI-e ports are available. It is unsupported to install any mezzanine cards, although three free slots exist on each blade.