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Load factor and rehashing in hashsets

  1. Oct 31, 2012 #1
    I had some general questions related to hashing.

    1. Load factor in a HashTable is when you want to increase capacity of buffer. Is there any advantage/disadvantage of setting the loadfactor less than 100% vs setting load factor at 100%?

    2. When you increase capacity, you have to rehash all values inside. Is there any way to increase capacity without a rehash?

    This is crossposted on [stackoverflow]
  2. jcsd
  3. Oct 31, 2012 #2


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    Wiki article mentions overhead increases once the load factor exceeds about 2/3rds.


    Not mentioned is the time it takes to iniitialize a hash table to empty, which could be an issue with a huge hash table in an attempt to produce a very low load factor (or one with a huge capacity). I don't know how to optimize dynamic capacity.
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