ARM processors could potentially coexist with x86 processors from Intel or Advanced Micro Devices in server environments, with the use case being similar to CPUs and graphics processors in some supercomputers today, chip maker Calxeda said on Monday.
In hybrid server environments x86 processors could do the main processing, while off-loading specific tasks such as cloud processing to the more power-efficient ARM processors, said Karl Freund, vice president of marketing at Calxeda. Apache Hadoop, which enables data distribution for large data sets across servers, can help resolve some problems by abstracting processor platforms.
Using an ARM processor alongside x86 chips would be similar to using Nvidia graphics processors alongside x86 CPUs, Freund said. Complex scientific and math calculations are usually transferred to Nvidia's graphics processors by x86 processors in some of the world's fastest supercomputers today.
Calxeda makes chips based on the ARM processor design that are being used in prototype servers from Dell and Hewlett-Packard. The proof-of-concept servers are being deployed so customers can try out ARM, whose processor designs are found in most smartphones and tablets today. Data centers are ruled by x86, but companies are exploring the possibility of cutting power costs through ARM servers that can serve Web pages.
However, ARM servers are still in "beta" phase and trying to find a place in data centers, Freund said. ARM servers will likely be in an experimental phase until 2013, with installations of thousands of servers coming next year, Freund said.
Saving a few watts per server could help
AMD's recent announcement that it would include ARM's Cortex-A5 processor for security processing inside its x86 chips highlights the possibility of ARM coexisting with x86, said Jack Gold, principal analyst at J. Gold Associates. It is possible, in theory, to bring together x86 and ARM in server environments, and some companies like SeaMicro (which has been acquired by AMD) have been looking at bringing ARM into server environments.
ARM could be good for power-efficient processing at a low cost but has some performance and throughput issues, Gold said. Big Web companies are buying hundreds of thousands of servers to boost performance, and some companies may be willing to take a chance on using ARM and x86 in data centres to cut power costs. Saving a few watts per server in large installations can make a big difference in overall electricity bills, Gold said.
ARM is not built for high-speed throughput, and an interface would need to be built for x86 and ARM servers to handle communication, Gold said. An operating system like Linux would work effectively across both ARM and x86 processors.
Also, managing multiprocessor environments is not easy, which could prove to be a challenge for system administrators, Gold said. A multiplatform environment may work in large server installations if the application is well-defined, and if a balance can be struck on power consumption and performance.
"You have to figure out what you are optimising for," Gold said.
Dell and HP have acknowledged that ARM servers are not ready for production environments, and Calxeda is trying to raise awareness about its ARM-based chips by showing servers running its EnergyCore processors at the ongoing International Supercomputing Conference in Hamburg and the recent Computex trade show in Taipei.
Web-enabled frameworks are able to work
The server experimentation involves benchmarking and testing which programs would work best on ARM servers, and Freund said that organisations testing servers with Calxeda chips include the Massachusetts Institute of Technology and Sandia National Laboratories.
In some cases, customers have been able to run Web-enabled frameworks such as Java, LAMP (Linux, Apache server, MySQL, Python) and Ruby on Rails without changing code, Freund said. Calxeda cannot demonstrate Microsoft's .Net framework, and there's also a lot of work involved in porting legacy Fortran and C++ code, Freund said. A lot of the server software to date has been written for x86 processors, much like how a majority of the smartphone and tablet software is being written for ARM processors.
ARM processors currently support 32-bit addressing, but there is a server market for the architecture as some Web-based frameworks support 32-bit, Freund said.
Looking ahead, Calxeda also hopes to release chips with 64-bit ARM processors, Freund said, though he couldn't give a specific release date. ARM has already announced the ARMv8 64-bit architecture, and it is due to announce its first 64-bit processors later this year. ARM has said that chips from licensees based on ARMv8 will be in volume production in late 2013 or 2014.