ARM gives us a glimpse of what to come

Although ARM has already announced its next gen Cortex-A15 core based on the ARMv7 architecture some time ago, the company has now unveiled some details of its upcoming ARMv8 architecture. The biggest and possibly most important change, depending on how things move forward in the universe of ARM powered devices, is 64-bit support in ARMv8.The ARMv8 architecture is a major step forward for ARM, at least when it comes to making processors that arent necessarily the most power frugal chips out there. With a clear move towards more ARM powered devices outside of the phone space, ARM needs to up its game and offer competitive processor cores on more than one level. With Windows 8 adding ARM support and maybe even more importantly, the server market starting to show interest in ARM powered servers, being able to address more than 4GB of RAM. However, ARM already supports virtual memory addresses of 40-bit or larger and that gives the ARMv7 architecture the option to support up to 1TB of RAM.Even so, a move towards 64-bit is going to be a must as operating systems, especially the ones from Microsoft, looks set to move to 64-bit only in the future, as there simply is no need to have separate 32-bit and 64-bit versions of Windows these days. Native 64-bit support should also offer better performance than virtual memory addressing, as the latter adds a performance hit. Another reason for 64-bit support is as mentioned, servers and with todays virtualized server environments, having 64-bit memory support is going to be a must for ARM if they want to compete with the big boys.ARM will of course continue to use its current technology and further enhance them in the ARMv8 and well see improved versions of TrustZone, virtualization and NEON advanced SIMD. What isnt mentioned are any additional features beyond the 64-bit addition to the ARMv8 architecture, but depending on where ARM and its partners want to take things, well most likely see a big change when it comes to power efficiency and thermals, at least for high-end cores that will end up both consumer devices and servers. In as much as were expecting new low-power solutions for phones and tablets, ARM and its partners are clearly taking the game to Intel and something is going to have to change if they want to compete on equal terms.That said, we doubt that well see power hungry processors based on ARMs technology, at least not compared to x86 based processors. There is a fine line between enough performance and power efficiency and ARM is likely to have to cross that line to stay competitive in the long term. The easy way to get more performance, at least in some scenarios is to add more cores and this is reasonably easy to do with ARM based technology, especially if you use multiple chips which are smaller and run cooler than x86 processors. More cores are great, except as AMD showed with its Bulldozer based FX series of consumer CPUs, having more cores doesnt always translate to real world performance gains. On the other hand, were not expecting to see a huge influx in cores when it comes to consumer processor designs from ARM, instead the company is going to have to come up with some new, clever ways of doing things.Of course, moving to new manufacturing technologies will help ARM and its partners to keep the power envelope down, for now at least, but the next step beyond 28nm is going to take a while, at least if the move from 40nm to 28nm is anything to go by. Yes, the foundries have roadmaps, but its worth taking into consideration that TSMC has decided to cut its capex for the next year or so with yet another global downturn being expected. This implies that we might have to live with 28nm chips for a bit longer than originally though. Then again, ARM is only expecting to disclose its first processors based on the ARMv8 architecture sometime next year and doesnt expect its partners to have any prototypes ready until 2014 which right now is an awfully long time away for a new processor technology.Source: ARM