Skip to content

Specialized GroupValues for primitive and large_primitive #16135

@Rachelint

Description

@Rachelint

Is your feature request related to a problem or challenge?

After #15961, in GroupValuesPrimitive, we store the hash of group to speed up rehashing.

However, I found the bottleneck of rehashing is not hash computation, it is actually randomly access to the values.

So, after experimenting, the better is:

  • We directly store the group value in map
  • So, during probing we can perform eq in-place
  • And, during rehashing we just perform the cheap hash computation for group value

But for the large primitives, it may be still better to store their hashes in map rather than themselves, otherwise it will make map too large and lead to possible regression.

Describe the solution you'd like

No response

Describe alternatives you've considered

No response

Additional context

No response

Metadata

Metadata

Assignees

No one assigned

    Labels

    enhancementNew feature or request

    Type

    No type

    Projects

    No projects

    Milestone

    No milestone

    Relationships

    None yet

    Development

    No branches or pull requests

    Issue actions