Cluster Computing In Space-constrained Applications

Today’s embedded computing applications areA chassis with four dual-processor Trenton SHBs can
far more sophisticated than those of the recent past.run up to 32 different applications—one for each
Industries such as medical imaging, homeland securityprocessor core in the chassis. This means that one
and military defense call for rackmount systems that5U rackmount computer, with four dual-processor
can run a growing number of complex softwareSHBs, can take the place of sixteen 1U dual
applications. In many of these industries the reliableprocessor motherboard systems. Using a single 5U
and timely processing of information can mean theenclosure instead of sixteen 1U enclosures reduces
difference between life and death. These industriesrack space by 19.25” (48.90cm)—a nearly 70%
also require equipment that can squeeze into tightlysavings.
constrained spaces and, in some cases, meet lowRemember that an aircraft can have up to seventy
weight requirements. Providing the needed computesystems, so this space savings is repeated many
capability inside this space and weight envelope is atimes throughout the plane. The space savings
considerable challenge.supplied by the Trenton cluster computer solution
In the medical imaging field, applications vary fromalso comes with a cumulative weight savings
simple single slice x-ray machines to three-dimensional,advantage because the solution requires fewer
multi-image slice CAT scan machines. Although thesecables, enclosures and computer power supplies.
applications have widely differing computeSo far we have only briefly outlined the features of
requirements, they share a need for increased imagethe system host boards. In the following sections we
clarity. This is driving a quest for higher-performancetake a closer look at the technologies in the two
rackmount systems. At the same time, the overallSHBs used in this application, the Trenton TQ9
size of the imaging machines is shrinking.System Host Board and the Trenton MCXT System
In the area of homeland security, cryptographyHost Board.
analysis is a key element in understanding what theTrenton TQ9 System Host Board (SHB)
bad guys are planning. Cryptography analysis systemsThe TQ9 is a single-processor, graphics-class PICMG
must process an extraordinary amount of incoming1.3 system host board. Among other responsibilities,
data from a wide variety of sources. These systemsthe TQ9 helps render information for analysis by
require advanced software that can sort out theintelligence specialists. As a graphics-class board, the
incoming data in order to allow intelligence specialistsTQ9 supports one x16 and one x4 PCIe electrical link.
to focus on the most important information. To meetThe x16 PCIe link is a common edge card connector
these needs, rackmount systems must provideinterface on many high-end graphics cards. This link is
scalable performance in relatively small enclosures.useful for aircraft systems that require video or
Surveillance aircraft represent a small slice of theother high-performance graphics. The x4 PCIe link
overall military defense market, but they illustratemay be used on a backplane as four individual x1
many of the challenges facing the rackmount systemPCIe links, giving designers an added degree of
designer. Surveillance aircraft provide locationflexibility.
information and near-real-time situational analysis—aIn this application, the TQ9 is configured with the
critical role in today's military, where information is asIntel® Core™ 2 Quad Processor Q9400. This
essential as firepower. Fulfilling this mission requires anprocessor features a quad-core design, a 1333 MHz
enormous amount of computational horsepower.front side bus and Intel® Virtualization Technology.
A typical airplane may have seventy computerVirtualization enables multiple operating systems to
systems dedicated to different aspects of therun on the TQ9, which in turn allows the end user to
surveillance mission. The computer systems must alsorun multiple applications on the same SHB. The TQ9
be flexible enough to handle the multiple systemalso comes equipped with the Intel® Q35 Express
configurations used in the aircraft. The computersChipset, which incorporates a 3D graphics accelerator.
must have a long service life and a stable systemOther TQ9 features include:
configuration to meet the aircraft’s long- Four DDR2-800 sockets supporting up to 8GB of
deployment and refurbishment schedules. Military endsystem memory
users require the use of commercial off-the-shelf- Four SATA II 300 interfaces with RAID support
(COTS) technology whenever possible.- On-board audio and video support
In this article we will use surveillance aircraft as an- Eight USB 2.0 interfaces
example of rackmount system design challenges. We- Support for an I/O expansion board, including an
will show how designers can meet these dauntingoptional TPM 1.2 module
challenges by using cluster computers, which groupThe Intel parts used in this design are long-life
single board computers together in a commonproducts supported by the Intel® Embedded and
chassis. We will outline the features and benefits of aCommunication Group. The long-life product support
cluster computer that incorporates quad-coreallows Trenton to meet the stability and longevity
Intel® Architecture processors, Trenton’srequirements of surveillance aircraft applications.
PCI Express® single board computers, andTrenton designs in other extended life components
multi-segment, passive backplanes.to ensure that the completed systems meet and
Chassis & Backplane Designexceed the deployment cycle requirements for the
Weight and space are at a premium on a surveillanceaircraft.
aircraft. Additional computer hardware has anTrenton MCXT System Host Board (SHB)
exponential effect on the cost of operating theThe MCXT is a dual-processor, server-class PICMG 1.3
aircraft. In addition to increasing the fuel costs, extrasystem host board. This SHB supports one x4 and
equipment weight creates mission delays due to thetwo x8 PCIe links down to the backplane. The MCXT
need for more frequent mid-air refueling. Trentonis used to handle the heaviest loads of data and the
addressed both the space and weight issues bymost complex situational analysis software on the
developing a shallow-depth chassis made out ofaircraft.
lightweight aluminum.The MCXT configurations on the plane use the
The most common rackmount chassis used on thequad-core Intel® Xeon® Processor E5440 and
aircraft has a depth of 18” (45.72cm) and a 5Uthe Intel® 5000P chipset. Both processors on the
chassis height. Each system has a multi-segmentMCXT communicate directly to the chipset along
PICMG® 1.3 backplane that enables multiple singleindependent, 1333 MHz front side busses. The chipset
board computers (SBCs) or system host boardsin turn features a four-channel DDR2-667 memory
(SHBs) to function in a single chassis. Other chassisinterface. As with the TQ9, this Trenton MCXT SHB
design elements include individual SBC segment powerconfiguration features long-life devices that support
control, quick access storage drives, corrosionIntel® Virtualization Technology.
resistant metal work, a high-performance coolingOther MCXT features include:
system and armored cable sleeves for vibration- Four DDR2-667 FB-DIMM sockets supporting up to
protection.16GB of system memory
The backplane is often a frequently overlooked- Six SATA II 300 interfaces with RAID support
component of an embedded computing system, but- On-board SXGA video support
it is an essential element of a high-performance- Four USB 2.0 interfaces
embedded design. Today’s higher bandwidth- Support for a x4 PCI Express link expansion
card-to-card interfaces such as a PCI Express®Cluster Computing System Design — Summary
(PCIe) demand robust backplane designs in order to& Conclusion
maintain optimum system throughput. For thisThe design objectives for surveillance aircraft are
system, we used the four-segment Trentonchallenging but are certainly not unique. Equipment
BP4FS6890 backplane. This multi-segment PICMG 1.3space constraints also exist in medical imaging
backplane is available in server-class or graphics-classsystems, cryptography analysis, telecom, industrial
configurations.automation, and many other applications.
The PICMG 1.3 backplane supports one or moreTrenton single board computers and multi-segment
SHBs, as well as industry standard COTS optionbackplanes bring the same space and efficiency
cards for functions including communications, video,benefits seen in the surveillance aircraft to a wide
sound, and data storage. This design allows designersvariety of embedded computing applications. Many
to mix and match single board computer capabilitiesapplications need to run different applications on a
based on the needs of the application.single platform, and single board computers and
System Host Boardsbackplanes have long made this possible. This basic
As noted above, up to four SHBs can be used in aarchitecture design advantage is now coupled with
single chassis. The SHBs can function together as athe Intel® Virtualization Technology. This potent
computer cluster, where all boards work together oncombination gives system designers the ability to
the same application. Alternatively, each SHB in theleverage the benefit of cluster computing across a
chassis can act as a computer unto itself. Intel®broad range of industry applications.
Virtualization Technology (Intel® VT) takes thisPICMG is a registered trademark of the PCI Industrial
concept further by allowing a single SHB to runComputer Manufacturers Group. Intel, Intel Xeon,
multiple independent operating systems andIntel Core 2 are trademarks or registered trademark
applications. The combination of the multi-SHB chassisof Intel Corporation. All other product and/or
and Intel® VT saves rack space by allowing acompany names are trademarks or registered
single chassis to run many independent applications.trademarks of their respective owners.