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Why moving to 64-bit processors may not benefit Android

After the announcement of Apple’s A7 chip, there has been a lot of hype over the future of 64-bit architecture in mobile devices. Not wanting to be left behind, Samsung quickly announced that its next smartphones will feature 64-bit processors.

A brief history of the 64-bit processor

Although some would argue that 64-bit computing only became mainstream with the advent of Windows 7, the reality is that this is a technology that has been widely used in other popular consumer products. Both the Nintendo 64 and PlayStation 2 were 64-bit consoles.

Windows XP 64-Bit Edition was actually released way back in 2001, although this was aimed squarely at those running the type of hardware typically found in servers.

AMD released the first 64-bit PC processor aimed at consumers in 2003, and this was supported by Microsoft with the 2005 release of Windows XP Professional x64 Edition.

What is a 64-bit processor?

In order to understand whether 64-bit computing might benefit Android, let’s first recap exactly what the technology offers.

A processor’s register is fast memory that is used for storing data that is frequently needed by the system. The greater the number of bits, the more of these commonly-used values that can be assigned by the register.

A 32-bit processor only has enough space to assign values for a maximum of 4 GB of system memory. By contrast, a 64-bit processor can access 17.2 billion GB (256 TB) of memory.

The benefits of 64-bit architecture

The ability to use more than 4 GB of RAM is the benefit that has received most attention, amongst the recent discussion of 64-bit computing. Whilst this is the main advantage offered by the change is system architecture, it would be disingenuous to state that it is the only advancement.

A larger register means that the processor is better able to handle complex calculations. For instance, a calculation with a 64-bit value could be handled in a single operation on a 64-bit processor, but would require two operations on a 32-bit processor.

As a result of this improved ability to handle large calculations, a 64-bit processor can prove faster when it comes to activities like gaming, image manipulation and video editing/encoding.

The problems of Android switching to 64-bit

Leading processor manufacturer ARM has already developed 64-bit architecture in the form of ARMv8. This is backward compatible with the 32-bit ARMv7, so running old apps won’t be an issue.

However, old apps will not be able to take advantage of the speed improvements offered by 64-bit architecture. Dedicated 64-bit apps will need to be developed in order to benefit from the new hardware.

Apple claim to have made 64-bit development easy for developers, and no doubt Google will do the same with any 64-bit release of Android. It remains to be seen, though, just how easy 64-bit programming is in reality, and how effectively compilers are able to take advantage of 64-bit hardware.

Most apps in Google Play have been developed by small teams with limited resources. Even if we do see 64-bit Android phones released next year, for many developers it will make sense to focus on 32-bit development, as devices running older architecture will make up the majority of the market for some time to come.

Does Android really need 64-bit processors?

Although 64-bit processors can prove faster than their 32-bit counterparts for certain intensive activities, those Android users who mainly play Angry Birds, surf the web and update their Twitter account would notice little improvement in speed.

If we are on the verge of a memory revolution, with countless Android devices running more than 4 GB RAM, then switching to 64-bit processors would be a wise move. But back in 2003, when AMD released the first 64-bit PC processor targeted at consumers, many believed we wouldn’t have to wait long before the memory limitations of 32-bit architecture were outgrown.

But now in 2013, ITProPortal report that the majority of gamers (53.96%) have 4 GB RAM or less. And this is a group of people renowned for investing in the latest and greatest hardware.

There are also factors specific to mobile devices that mean we are not likely to see manufacturers installing large amounts of memory in their devices anytime soon.

Memory is power-hungry. As a result, operating systems like Android have been designed to manage memory in a very efficient manner.

Although the forthcoming Samsung Galaxy Note 3 will pack 3 GB RAM, this is a large 5.7-inch device that is able to house a substantial 3200 mAh battery.

There is a risk that an early move to 64-bit hardware will see many consumers investing in technology they won’t be able to enjoy the benefits of for years.