the.com/load factor
how full your hash table is before it starts throwing tantrums.
means the ratio of stored elements to total available slots in a hash table, used to decide when to resize.
from borrowed from electrical engineering, where load factor meant average load over peak capacity; computer science stole the metaphor for hash tables in the 1960s-70s as open addressing schemes needed a threshold to trigger rehashing.
java defaulthashmap resizes at 0.75 load factor
tradeofflower factor wastes memory, higher causes collisions
open addressing limitperformance craters as factor nears 1.0
for instance
java hashmap — doubles capacity once load factor exceeds 0.75
python dict — resizes at two-thirds full, roughly 0.66
redis hash table — uses incremental rehashing to dodge load spikes