5 Replies
      Latest reply on Nov 4, 2016 1:19 AM by eskimo
      AlexSt Level 1 Level 1 (0 points)

        I'm experiencing a weird issue: on the 7 plus my app performs certain operations much faster when the system itself is under some load (for example, installing apps). The operations are mostly CPU-bound.

        Is it possible that iOS keeps running on low power A10 cores even when there's a third-party app in foreground?

        • Re: App on iPhone 7 Plus runs faster when system is busy
          eskimo Apple Staff Apple Staff (13,875 points)

          The operations are mostly CPU-bound.

          How are you running those operations?  With a thread?  Via an operation queue?  Via GCD?

          Have you set the quality of service for those operations?  The correct way to do that depends on your answer to the above, but the QoS values are unified across all of those APIs.  See for a summary of those values, or any one of a bunch of recent WWDC sessions [1].

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          [1] The concept was first introduced at WWDC 2014 and has featured heavily in WWDC performance talks since then, so many that it’s hard for me to provide all the links.  It’s probably best to start at the beginning, with WWDC 2014 Session 710 710 Writing Energy Efficient Code, Part 1.