Chip design firm ARM today announced the eighth generation of its ARM Instruction Set Architecture (ISA). The ARMv8 ISA extends the current ARMv7 architecture to include support for 64-bit addressing. The company said that this move would enable the architecture to be used in servers and other enterprise roles, bringing ARM’s low-power advantage to a market that’s increasingly challenged by power consumption and energy efficiency.
ARMv7 provides a 32-bit virtual address space, coupled with a 40-bit physical address space. This allows ARMv7 designs–including the Cortex A8 and Cortex A9 designs that power many smartphones, including Apple’s iPhone 4S–to give each application its own private allocation of 4GiB memory, and to address a total of 1TiB physical RAM.
For traditional ARM roles, including smartphones, 4GiB is plenty, but the company wants its architecture to break out of its current embedded niche. 64-bit virtual addressing allows applications to easily handle much more