What is the limitation on the number of elements that can be placed in a bucket in a Map implementation?

In the implementation of map in Go, elements are stored in buckets, each of which contains a limited number of elements. Currently (Go 1.20 and above), each bucket can hold up to 8 key-value pairs.

This limitation is due to the internal structure of the bucket, which is optimized for quick access and efficient memory usage. If a bucket contains more elements due to hash collisions, the map undergoes a rehash with an increased number of buckets.

Here's how the storage roughly works:

• Each bucket is an array of 8 slots for key-value pairs.
• When adding a 9th element with the same hash, a split occurs, and elements are redistributed across new buckets.

This allows for an effective balance between access speed and memory usage.