What is the advantage of Swiss Tables compared to the old hash table implementation? How many bits does the hash code occupy in the old and new implementations?

Swiss Tables are a modern implementation of hash tables that use open addressing with group search techniques and an optimized data structure to improve performance and reduce collisions.

Advantages of Swiss Tables compared to the old hash table implementation in Go:

• Uses SIMD instructions for fast comparison of multiple hash codes simultaneously.
• Hash codes are stored in a compact form (8 bits), reducing memory consumption and speeding up searches.
• More efficient collision management and fewer memory accesses.

In the old Go implementation, the hash code was 16 bits, while in Swiss Tables it is 8 bits. This reduction in hash code size allows more information to be stored in the CPU cache and speeds up search and insert operations.