VietMX Staff asked 3 years ago
Any Hash Table has two parameters that affect its performance: initial capacity and load factor. The capacity is the number of buckets in the hash table, and the initial capacity is simply the capacity at the time the hash table is created.
If the table size grows, hash tables tend to resize themselves (i.e. create a bigger array of buckets, create new/updated linked lists there-from, delete the old array) to keep the ratio of values to buckets (aka load factor) somewhere in the 0.5 to 1.0 range. The load factor is a measure of how full the hash table is allowed to get before its capacity is automatically increased.
As a general rule, the default load factor (.75) (used in Java HashMap) offers a good tradeoff between time and space costs. Higher values decrease the space overhead but increase the lookup cost.
