Messages in this thread | | | Date | Wed, 11 Apr 2007 15:06:44 -0700 (PDT) | From | David Lang <> | Subject | Re: If not readdir() then what? |
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On Thu, 12 Apr 2007, Neil Brown wrote:
> For the second. > You say that you " would need at least 96 bits in order to make that > guarantee; 64 bits of hash, plus a 32-bit count value in the hash > collision chain". I think 96 is a bit greedy. Surely 48 bits of > hash and 16 bits of collision-chain-position would plenty. You would > need 65537 entries before a collision was even possible, and > billions before it was at all likely. (How big does a set of 48bit > numbers have to get before the probability that "No subset of 65536 > numbers are all the same" drops below 0.95?)
Neil, you can get a hash collision with two entries.
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