Feeds

Cray launches Gemini super interconnect

Last Baker system component revealed

HP ProLiant Gen8: Integrated lifecycle automation

Another thing that Cray is adding back into its supers with the XE6 systems is global memory addressing, something that Cray machines have not had since the T3E super from 1995, which was based on the Digital Equipment Alpha 21164 processor. (Yes, DEC was a damned good engineering company.)

The T3E was the first machine to break the 1 teraflops barrier doing actual work. (I know about ASCI Red and its Linpack ratings.) The global address space in the XE6 is implemented in the Gemini chip and basically allows remote direct memory access (RDMA) from any node in the system to any other node in the system without having to go through the whole MPI stack to have nodes talk to each other.

This global address space is not as tight as the shared global memory that Silicon Graphics implements in NUMAlink 4 for its Itanium-based Altix 4700s or in NUMAlink 5 for its new Xeon 7500-based Altix UVs. Global shared memory in the SGI sense means there is only one copy of the Linux operating system and one address space for applications.

The global addressing based on RDMA that Cray is implementing in the XE6 provides a shared address space for applications, but each node in the cluster has its own copy of the Linux operating system. The "Blue Waters" massively parallel Power7-based super IBM is building for the University of Illinois has something akin to Cray's global addressing.

The global addressing means that applications running across a large number of nodes can be coded more easily than with MPI, but you have to use special languages like Unified Parallel C, Co-Array Fortran, Chapel (from Cray), or X10 (from IBM) to use it. The Cray X1 and X2 vector machines had global address spaces, and so too did the Quadrics interconnect, which is one reason why Duncan Roweth, one of the founders of the British HPC interconnect makers, took a job at Cray when Quadrics shut down a year ago. ®

Reducing security risks from open source software

More from The Register

next story
Sysadmin Day 2014: Quick, there's still time to get the beers in
He walked over the broken glass, killed the thugs... and er... reconnected the cables*
Amazon Reveals One Weird Trick: A Loss On Almost $20bn In Sales
Investors really hate it: Share price plunge as growth SLOWS in key AWS division
Auntie remains MYSTIFIED by that weekend BBC iPlayer and website outage
Still doing 'forensics' on the caching layer – Beeb digi wonk
SHOCK and AWS: The fall of Amazon's deflationary cloud
Just as Jeff Bezos did to books and CDs, Amazon's rivals are now doing to it
BlackBerry: Toss the server, mate... BES is in the CLOUD now
BlackBerry Enterprise Services takes aim at SMEs - but there's a catch
The triumph of VVOL: Everyone's jumping into bed with VMware
'Bandwagon'? Yes, we're on it and so what, say big dogs
Carbon tax repeal won't see data centre operators cut prices
Rackspace says electricity isn't a major cost, Equinix promises 'no levy'
prev story

Whitepapers

Designing a Defense for Mobile Applications
Learn about the various considerations for defending mobile applications - from the application architecture itself to the myriad testing technologies.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Top 8 considerations to enable and simplify mobility
In this whitepaper learn how to successfully add mobile capabilities simply and cost effectively.
Seven Steps to Software Security
Seven practical steps you can begin to take today to secure your applications and prevent the damages a successful cyber-attack can cause.
Boost IT visibility and business value
How building a great service catalog relieves pressure points and demonstrates the value of IT service management.