1. 15 Apr, 2014 1 commit
  2. 14 Apr, 2014 18 commits
  3. 13 Apr, 2014 3 commits
  4. 12 Apr, 2014 10 commits
  5. 11 Apr, 2014 4 commits
  6. 10 Apr, 2014 1 commit
    • antirez's avatar
      HyperLogLog sparse representation slightly modified. · 9c037ba8
      antirez authored
      After running a few simulations with different alternative encodings,
      it was found that the VAL opcode performs better using 5 bits for the
      value and 2 bits for the run length, at least for cardinalities in the
      range of interest.
      9c037ba8
  7. 09 Apr, 2014 1 commit
  8. 04 Apr, 2014 2 commits
    • antirez's avatar
      PFCOUNT: always unshare/decode the object. · d5be696d
      antirez authored
      This will be a non-op most of the times since the object will be
      unshared / decoded, however it is more technically correct to start this
      way since the object may be decoded even in the read-only code path.
      d5be696d
    • antirez's avatar
      Changed HyperLogLog hash seed to a non-zero value. · 433ce7f8
      antirez authored
      Using a seed of zero has the side effect of having the empty string
      hashing to what is a very special case in the context of HyperLogLog: a
      very long run of zeroes.
      
      This did not influenced the correctness of the result with 16k registers
      because of the harmonic mean, but still it is inconvenient that a so
      obvious value maps to a so special hash.
      
      The seed 0xadc83b19 is used instead, which is the first 64 bits of the
      SHA1 of the empty string.
      
      Reference: issue #1657.
      433ce7f8