• antirez's avatar
    Speedup hllRawSum() processing 8 bytes per iteration. · 5eb7ac0c
    antirez authored
    The internal HLL raw encoding used by PFCOUNT when merging multiple keys
    is aligned to 8 bits (1 byte per register) so we can exploit this to
    improve performances by processing multiple bytes per iteration.
    
    In benchmarks the new code was several times faster with HLLs with many
    registers set to zero, while no slowdown was observed with populated
    HLLs.
    5eb7ac0c
hyperloglog.c 56.1 KB