AMD aims to embrace and extend itself around parellelism
You down with LWP?
AMD has plotted out a path to add a pair of new extensions to its instruction set that should boost the performance of parallelized code.
As of today, AMD has released the "Light-Weight Profiling" (LWP) specification for review. The chipmaker likens the technology covered in the specification to similar hardware hooks it has built-in for code such as virtualization software. This time around, however, the new instructions should make things like runtimes cruise more efficiently across multi-core chips.
Improving the performance of software on multi-core chips has become crucial due to a disconnect between the hardware and software industries. Software developers became used to constant increases in chip speeds, which led to constant increases in single-threaded application performance. But chip makers are now focusing on placing numerous lower-power cores on a single chip, which means developers have to crank out multi-threaded code if they want to enjoy historic gains. Such code proves more complex to write, so any help from the likes of AMD or Intel is appreciated.
"The LWP specification describes the first technology that supports a recently introduced initiative called 'Hardware Extensions for Software Parallelism,' which will encompass a broad set of innovations designed to improve software parallelism, and thus application performance, through new hardware features in future versions of AMD processors," AMD said. "LWP is a CPU mechanism that could have broad benefit to software including, but not limited to, runtime environments such as Sun Microsystems' Java Virtual Machine and Microsoft's .NET Framework."
The specification now goes in front of developers who will provide feedback to AMD. It could take years before the new instructions covered in the spec actually appear in silicon.
Down the road, AMD may consider similar specifications for silicon boosts to transactional memory and high performance message passing.
The new instructions are pretty standard. There's one to turn LWP on and off and another that makes a call for specific information that may help with the whole LWP process.
The spec is available in its full glory here (PDF). ®