From: Vladimir Prus (ghost_at_[hidden])
Date: 2001-03-06 09:17:03
crc_fast, despite its name, has a significant performance problem. Namely, if
input is reversed, the code call a routine to reverse each byte. That
bit-tossing routine is slow, and as far as I can tell, all practical
implementation avoid reversing byte, but instread reverse everything else.
I compared performance of current crc_fast with implementation that uses
optimization mentioned above. On 1Meg buffer with random data crc_fast is
10 times slower. Without bytes reversing, it's only 2 times slower. So,
changing code seems worthwhile.
-- Regards, Vladimir
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