Feeds

IBM 1GHz 64-bit PPC to deliver 11,000 MIPS

Ultra SMP the way to go, says Big Blue

  • alert
  • submit to reddit

Mobile application security vulnerability report

More information is leaking out about the next generation IBM PowerPC Power4, the 64-bit chip line formerly known as Gigaprocessor, and due next year at clock speeds of over 1GHz. The first chips will be sub-0.18 micron, with 200 million transistors or more. Power4 will have two microprocessors on a single piece of silicon, and at 1.1GHz should be able to deliver 11,000 MIPS. The architecture comes out of Austin, and chips will be fabbed at the Fishkill Semiconductor Center. With microprocessor performance still increasing much faster than memory hierarchy performance, DRAM latency will grow and bus speed will not keep pace with increases in microprocessor speed. Likewise, circuit density will continue to increase faster than circuit speed. To leverage the circuit density increase, faster uniprocessors with superscalar designs or VLIW and derivatives such as EPIC (explicitly parallel instruction computing, favoured by Intel) are needed. More systems functions and multiple processors on a chip (SMP, co-processors and redundant processors for error detection and fault tolerance) seems to be IBM's preferred route. Whatever the architecture or design, processors spend most of their time waiting for cache misses, so the optimised feeding of processors is the main performance challenge. Software design trends such as OOP and JIT compilation will increase the memory hierarchy load, so the design challenge is to deal with the memory hierarchy bandwidth. IBM says it believes that its approach to parallelism (Ultra SMP) is superior to Intel's EPIC since EPIC increases the demand for memory hierarchy bandwidth and low latency. IBM also claims that EPIC is less suitable for JIT Java compilation as it needs lengthy compilation and a large optimisation window. Another difficulty that IBM identifies with EPIC is in future binary compatibility, resulting in a probable need to recompile. Could it be that a JavaOS will rise again? Explicit parallelism -- Ultra SMP -- is IBM's answer, which it claims exploits existing parallelism in code (and particularly SMP-enabled server applications with multiple threads). The approach allows multiple threads per chip with multiple physical processors, or multiple logical processors with hardware thread switching. Above all, the memory hierarchy would be used more efficiently, IBM says, with less bandwidth for each useful instruction, as well as less cache latency. As a consequence, IBM will preserve PowerPC and S/390 binary compatibility, and optimise for SMP and cluster performance with multiple RISC "cores" per chip, while Intel creates a new IA-64 instruction set architecture and optimises uniprocessor performance. IBM won't have the fastest uniprocessor, but it should do a better job of preserving the software investment. Intel is left with some sticky problems, such as software migration; performance issues with the new architecture; x86 compatibility mode performance; and SMP performance. These puddings aren't yet ready for eating -- and there are other chefs too -- so we'll just have to wait and see which proves tastier. ®

The Power of One Brief: Top reasons to choose HP BladeSystem

More from The Register

next story
BBC goes offline in MASSIVE COCKUP: Stephen Fry partly muzzled
Auntie tight-lipped as major outage rolls on
iPad? More like iFAD: We reveal why Apple fell into IBM's arms
But never fear fanbois, you're still lapping up iPhones, Macs
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
Bose says today is F*** With Dre Day: Beats sued in patent battle
Music gear giant seeks some of that sweet, sweet Apple pie
There's NOTHING on TV in Europe – American video DOMINATES
Even France's mega subsidies don't stop US content onslaught
You! Pirate! Stop pirating, or we shall admonish you politely. Repeatedly, if necessary
And we shall go about telling people you smell. No, not really
Too many IT conferences to cover? MICROSOFT to the RESCUE!
Yet more word of cuts emerges from Redmond
Chips are down at Broadcom: Thousands of workers laid off
Cellphone baseband device biz shuttered
Twitch rich as Google flicks $1bn hitch switch, claims snitch
Gameplay streaming biz and search king refuse to deny fresh gobble rumors
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.