What is the procedure called for moving data to another part of memory when expanding a Map data structure?

The procedure of moving data to another part of memory when expanding the Map data structure in Go is called rehashing.

When a hash table (map) reaches a certain fill threshold, the elements are redistributed into a new, larger table. This involves:

• Allocating a new block of memory of larger size.
• Moving (copying) all existing key-value pairs into the new table with recalculated hashes.

This is necessary to maintain the efficiency of search and insert operations.

It looks roughly like this internally, but in Go, it happens automatically and transparently for the user.