iOS 15.2 takes too long for calculations.

Then the worst case of your algorithm needs improvement. What does the calculation pattern look like? Is the input driven by data? How many dimensions or for loops process this data? Is my algorithm more efficient with small amounts of data but takes longer as the data get larger? Answer those questions then look for ways to improve any pattern that might be causing the issue. Iteration vs recursion, those types of questions. Now the question is if it's your API then think about how to improve it. If it is not yours then file a bug with the creator of the particular api.

a complex calculation

• Could you tell more about this calculation ? Eventually post the code ?
• Which func or API does it call ?

Have you tried to use Instruments to get a profile of where you spend most time in calculation ?

Same issue reported here (Sorry, I just notice both threads are yours! aka duplicate). https://developer.apple.com/forums/edit/answer/700929022

In both case that's iPadOS 15.2 with objC code.

Does the problem show on iOS ?

Could be worth a bug report.

For those reading along at home there’s a code snippet in the Basith128’s other thread.

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Quinn “The Eskimo!” @ Developer Technical Support @ Apple
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For those reading along at home there’s a code snippet in the Basith128’s other thread.

It’s hard to say what’s going on here without more context. Your other thread has a small code snippet but that’s not really enough. Can you boil this down to a self-contained test that demos the performance difference?

Also, does this problem reproduce in the simulator? Generally it’s a bad idea to use the simulator to test performance but this error is big enough that it might show up there too.

Share and Enjoy
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Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"