Improve Huffman decoding speed using table-based implementation. #35
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This is heavily inspired by the work done by @tatsuhiro-t for nghttp2, and ported to Python. In some micro-benchmarks focusing on decoding primarily ASCII-text, the Huffman decoder in the form of this unrolled state machine performs 4x faster than the naive Python version used elsewhere in the HPACK module, decompressing a 1kB Huffman string in ~600usec compared to the naive version's 2.4msec. This is without question a micro-optimisation, but given that the table is not in flux anymore there's little advantage to using the naive Huffman decoder. Enormous gratitude is owed to @tatsuhiro-t for his work on this decoder.
Lukasa
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Improve Huffman decoding speed using table-based implementation.
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This is heavily inspired by the work done by @tatsuhiro-t for nghttp2, and ported to Python. In some micro-benchmarks focusing on decoding primarily ASCII-text, the Huffman decoder in the form of this unrolled state machine performs 4x faster than the naive Python version used elsewhere in the HPACK module, decompressing a 1kB Huffman string in ~600usec compared to the naive version's 2.4msec.
This is without question a micro-optimisation, but given that the table is not in flux anymore there's little advantage to using the naive Huffman decoder.
Enormous gratitude is owed to @tatsuhiro-t for his work on this decoder.