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javaycsbbigdatadatabase

What is the alpha parameter of YCSB zipf distribution

YCSB comes with a ZipfianGenerator class, what is the alpha of this zipfian distribution?

Solution

  • By checking the ZipfianGenerator code in the repository, the default value for alpha is 1/(1-theta) (line 142).

    Theta is the 'zipfian constant' (line 137). Its default value is 0.99 (line 42), which gives an alpha value of 100.

    You can specify a different theta in the constructor to get a different alpha value.