gh-155152: Fix quadratic processing of concatenated zstd frames in zipimport - #155154
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gh-155152: Fix quadratic processing of concatenated zstd frames in zipimport#155154lpyu001 wants to merge 1 commit into
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August 4, 2026 08:48
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The implementation uses _zstd.get_frame_size() to determine the compressed size of each Zstandard frame and passes only that frame to the decompressor. A memoryview enables zero-copy slicing while advancing through the input. This ensures each compressed byte is processed once, reducing cumulative input handling from O(N²) to O(N).
zipimport._zstd_decompress()repeatedly processes remaining input for concatenated frames #155152