The eight-core era arrives

The eight-core era arrives

Summary: Samsung is set to start making its Exynos 5 Octa and other chipmakers aren't far behind, even though few apps are designed to really take advantage of many-core processors. The real reason mobile chipmakers are pushing eight cores may simply be because they can.


I’ve been skeptical of the core wars in mobile. But it turns out we’re going to get eight-core processors whether we need them or not.

Samsung Eyxnos 5 Octa
Samsung's Exynos 5 Octa combines a high-performance Cortex-A15 quad-core and a low-power Cortex-A7 quad-core. It is designed for high-end tablets and smartphones.

On the heels of the launch of the Galaxy S4 smartphone, Samsung announced that it is about to start cranking out the Exynos 5 Octa eight-core processor. Renesas isn’t far behind with its APE6 eight-core chip and ARM has said five more chipmakers will be announcing multi-core processors using its so-called big.LITTLE architecture this year.

The Exynos 5 Octa won’t show up in the U.S. version of the Galaxy S4, which will instead rely on a Qualcomm 1.9GHz quad-core Snapdragon, but it will reportedly be used in the S4 in other markets--and it will be used in other high-end smartphones and tablets. The processor is a technological marvel. Manufactured on Samsung’s advanced 28nm process, it has four high-performance Cortex-A15 cores and four low-power Cortex-A7 cores. Although Samsung has been quiet about it, Imagination Technologies confirmed earlier this week that the processor is using its PowerVR SGX544MP multi-core graphics. Samsung said the processor delivers twice the graphics performance of its Exynos 4 Quad and supports WQXGA (2560x1600) displays.

This is all pretty impressive. But it seems a bit strange to have eight-core processors in smartphones when most PCs are getting by just fine with dual-cores (or quad-cores in high-end systems). The truth is that very few apps are designed to really take advantage of four cores let alone eight. Furthermore many applications that really need a lot of horsepower are already off-loaded to specialized hardware. The Exynos 5 Octa has a hardware engine that can record and play Full HD video at up to 60 frames per second and an image processor that can capture 13-megapixel shots at 30 frames per second, according to Samsung.

The real reason mobile chipmakers are pushing to eight-core may simply be because they can. The size of a chip determines how much it costs to manufacture. A chip with eight Cortex-A15 cores would be too large (and use too much power), but the A7 cores are tiny and ARM has already done much of the heavy lifting to make them work well together. At a recent chip conference, Samsung said that the A15 delivers 3x the performance of the A7, but it is also four times larger and uses 6x more power. So with big.LITTLE chipmakers and their customers get the best of both worlds: they can market it as an eight-core processor, but it has manufacturing cost and battery life of a quad-core chip. While it is a bit misleading, it’s good for users too. Most of the time you will be using only one or two cores, but the extra performance is there if you need it.

Nvidia was the first to adopt this companion core concept in its Tegra mobile processor, but it uses all of the same type of CPU cores running at different speeds. The Tegra 4 for tablets has four 1.9GHz A15s and a companion A15 core clocked at only 825MHz; the Tegra 4i for smartphones has four 2.3GHz A9s and a fifth “battery-saver” A9 core.

Intel insists that its manufacturing process and design allows the same cores to support a wide range of speeds so it doesn’t really need to mix and match different types of cores. They use relatively little power when they are not being taxed heavily, but can spike up to higher frequencies when needed. Over time the x86 processors in laptops look more and more like the System-on-Chip (SoC) designs in mobile devices, so we could eventually see these sorts of heterogeneous cores in future PCs too.

Topics: Processors, Smartphones, Tablets

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  • All these lovely cores

    Yet multicore programming techniques lag behind by decades.

    Hands up who remembers the transputer.
    Alan Smithie
    • Isn't dual CPU SoC more accurate

      Than 8 core processor?

      After all isn't the point that the OS chooses which CPU to use; power effient or powerful?
      • My thought as well. It is really a dual quad setup.

        Allowing upto 4 simultaneous threads. It will be interesting to see how the load is balanced between different needs.
        • Bruizer, you are an apple fanboy, perhaps you know?

          Since you believe Samsung is a me-too copier of everything apple does, which or apple's chip designs did Samsung copy this from?
          • curious

            Since when fanboys know factual information?
          • Re: which or apple's chip designs did Samsung copy this from?

            They copied Apple's dual-core configuration, but they copied it four times.
          • You can't make this up.

            You hate Apple so much, you make every post about Apple.

            Seriously, you can't make this stuff up.
          • Kudos!


            Keep up the trolling and dark comedy. Seems these people take everything you write seriously as if you really know what you are talking about on the technical level. Of course, it wouldn't surprise me that your reading this comment from your Apple iPhone 5.

            DarkWorks Entertainment
          • DarkWorks Entertainment....he not nearly as funny as the King of Zdnet

            Zdnet own Loverock Davidson
            Over and Out
    • transputer

      so someone read byte magazine back in the day congratulations !!!
  • I barely have much use of quad-core CPUs on my desktop PC

    Will someone tell me why I need 8-core in a smart phone? Or is it another proof that Android is simply a computing-hog that runs smoothly only on top of tuned-up hardware.
    • 4 for "power" and 4 for "easy tasks" that switch, it only use 4 at a time

      depending on the task you're doing. IMO, it would be more effective to just have 4 cores that automatically adjust frequency and output, and focus on the performance per core, & have them ramp down the clock on the ones in use to save power for tasks that take less power.
      • They already do

        Control panel > power options > Change plan settings > Change Advanced Power settings > Processor Power Management.

        Of course your hardware must support this and most have for several years now years. Intel calls it "Speedstep". AMD calls it "Powernow".
  • kiss

    I always wonder why all these "me too" device/chip makers would not learn that simpler designs ate more effective.

    It does not matter how many cores the thing has - all that maters are what actual performance is provided, at what cost (power used, heat, space) and how much it all costs.

    There are no problems to produce 16 core A15 chip, but all it will do is consume mor power.
    • That answers my question

      I was going to ask how many cores an iphone had but you answered it: fewer than 8.

      The instant that an iphone has more cores than another phone though, suddenly, number of cores will be important.
      • Technically, it's not really an "8 core" chip

        It's more of two quad core chips that switch, one for demanding tasks and one for easier tasks (allot like nvidia's tegra 3, actually. It has a fifth low power core that but it isn't advertised much).
      • Apple cores

        ((( "I was going to ask how many cores an iphone had but you answered it: fewer than 8." )))

        It is no great triumph to have eight unoptimized cores that sit idle the overwhelming majority of the time. As the author noted, there are virtually no Android apps that take advantage of multiple cores, so it's really a wasted effort to include them. That's not the case with iOS, however, which includes Apple's Grand Central Dispatch technology to efficiently utilize an arbitrary number of processors and cores. As a result, there are many iOS apps which support multiple cores, since there is so little heavy-lifting involved for iOS developers to include it.
        • Ummm... what?


          You should read this.

          The optimization is done at the software level. Please read it and educate yourself.
    • The other truly fascinating thing about your post

      You start by calling these me-too devides.

      You then spend the rest of your post detailing how these are very different from apple devices.

      Too funny, you just can't make this stuff up.
      • What is even funnier is...

        He never mentioned Apple. You just made it up.

        Seriously, you can't make this stuff up.