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An 8 core processor on a Macbook Air that is also energy efficient? That is truly impressive. I never thought I would consider using Macbook Airs after all the

• BooneJS 6y ago
  4 high-power and 4 low-power cores.
  • jagger27 6y ago
    At 9:15 of the keynote they claim that the "high-efficiency" cores are as powerful as the outgoing dual-core MacBook Air's cores. Seems pretty good to me.
    • BooneJS 6y ago
      Agreed, but I wish I knew the numbers behind those statements.
• cornstalks 6y ago
  It's 8-core, but they're 4 performance and 4 low-power cores, so it's not your normal 8-core chip. It's more like a big.LITTLE chip.
  • semi-extrinsic 6y ago
    Anyone know how you interact with these cores as a developer/user? Say if I'm running some C code with OpenMP parallelism, can I bind it to three of the fast cores?
    • saagarjha 6y ago
      Binding to specific cores is not exposed to userspace, but you can influence which kinds of cores it's likely to be run on by setting thread priorities and QoS classes.
    • TkTech 6y ago
      With ARM, yes, and you can also selectively turn on and off cores. For example when travelling with my pinebook pro I turn the big cores off to drastically improve battery life. However it's up to Apple to expose this functionality, and we all know how much control apple wants you to have of the computers you "license" from them.
      • mouldysammich 6y ago
        WRT the pinebook, i didnt know it could do that. can it be done at runtime or do you have to change it at boot time?
        • TkTech 6y ago
          They can be onlined or offlined at any time, To offline a core: echo 0 > /sys/devices/system/cpu/cpuN/online To online a core: echo 1 > /sys/devices/system/cpu/cpuN/online Where cpuN is 0-4. Keep in mind there's always one core you cannot disable to process interrupts.
          • mouldysammich 6y ago
            Very cool, thank you.
          • dannyw 6y ago
            That sounds awesome. Sounds really fun to hack around. I might buy a Pinebook
    • heavyset_go 6y ago
      The macOS SDK exposes a processor affinity API that you can program against. There isn't an option like taskset on Linux to pin or move tasks among different cores, or like anything that's exposed in Linux's sysfs.
• berkut 6y ago
  Seems pretty clear they're using big.LITTLE-style low-power and high-power cores on the same chip. No fan however, is impressive....
  • soziawa 6y ago
    But it can't sustain max performance. That is reserved for the MacBook Pro with a fan.