By
Tom Krazit
Monday, February 12 2007 09:40 AM
URL:
http://www.zdnetasia.com/news/hardware/0,39042972,61989200,00.htm
Intel has built its 80-core processor as part of a research project, but
don't expect it to boost your Doom score just yet.
Chief Technical Officer Justin Rattner demonstrated the processor in San
Francisco last week for a group of reporters, and the company will present a
paper on the project during the International Solid State Circuits
Conference in the city last week.
The chip is capable of producing 1 trillion floating-point operations per
second, known as a teraflop. That is a level of performance that required 2,500
square feet of large computers a decade ago.
Intel first disclosed it had built a prototype
80-core processor during last year's Intel Developer Forum, when CEO Paul
Otellini promised to deliver the chip within five years. The company's
researchers have several hurdles to overcome before PCs and servers come with
80-core processors--such as how to connect the chip to memory and how to teach
software developers to write programs for it--but the research chip is an
important step, Rattner said.
A company called ClearSpeed has put 96 cores on a single chip. ClearSpeed's chips are used as
co-processors with supercomputers that require a powerful chip for a very
specific purpose.
Intel's research chip has 80 cores, or "tiles," Rattner said. Each tile has a
computing element and a router, allowing it to crunch data individually and
transport that data to neighboring tiles.
Intel used 100 million transistors on the chip, which measures 275
millimeters squared. By comparison, its Core 2 Duo chip uses 291 million
transistors and measures 143 millimeters squared. The chip was built using
Intel's 65-nanometer manufacturing technology, but any likely product based on
the design would probably use a future process based on smaller transistors. A
chip the size of the current research chip is likely too large for
cost-effective manufacturing.
The computing elements are very basic and do not use the x86 instruction set
used by Intel and Advanced Micro Devices' chips, which means Windows Vista can't
be run on the research chip. Instead, the chip uses a VLIW (very long
instruction word) architecture, a simpler approach to computing than the x86
instruction set.
There is also no way at present to connect this chip to memory. Intel is
working on a stacked memory chip that it could place on top of the research
chip, and it is talking to memory companies about next-generation designs for
memory chips, Rattner said.
Intel's researchers will then have to figure out how to create
general-purpose processing cores that can handle the wide variety of
applications in the world. The company is still looking at a five-year timeframe
for product delivery, Rattner said.
But the primary challenge for an 80-core chip will be figuring out how to
write software that can take advantage of all that horsepower. The PC software
community is just starting to get its hands around multicore programming,
although its server counterparts are a little further ahead. Still, Microsoft,
Apple and the Linux community have a long way to go before they will be able to
effectively utilize 80 individual processing units with their PC operating
systems.
"The operating system has the most control over the CPU, and it's got to
change," said Jim McGregor, an analyst at In-Stat. "It has to be more
intelligent about breaking things up," he said, referring to how tasks are
divided among multiple processing cores.
"I think we're sort of all moving forward here together," Rattner said. "As
the core count grows and people get the skills to use them effectively, these
applications will come." Intel hopes to make it easier by training its army of
software developers on creating tools and libraries, he said.
Intel demonstrated the chip running an application created for solving differential
equations. At 3.16GHz and with 0.95 volts applied to the processor, it can
hit 1 teraflop of performance while consuming 62 watts of power. Intel
constructed a special motherboard and cooling system for the demonstration in a
San Francisco hotel.