Reduce high CPU usage during downloads #291
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pcuenca
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Nov 24, 2025
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This looks ok to me. Do you have any feedback @ardaatahan?
pcuenca
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Nov 26, 2025
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I noticed that CPU usage in my app was above 300% during 4 concurrent model downloads. I made some changes that appear to reduce the CPU usage by about half:
ContiguousArray<UInt8>is used for collecting batches instead ofArray<UInt8>.TaskGroupon each update was removed.The use of
URLSession.bytes(for:)is inherently expensive due to the processing of bytes one at a time in anAsyncSequence, but I'm not sure if there's a better alternative that allows for resumable downloads.