Skip to content

Use a single HashMap implementation consistently across the code base #677

@houqp

Description

@houqp

Is your feature request related to a problem or challenge? Please describe what you are trying to do.
A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]
(This section helps Arrow developers understand the context and why for this feature, in addition to the what)

We are using both std::collections::HashMap and hashbrown::HashMap in datafusion, it would be better to consistently use only one of them.

hashbrown's official readme has the following statement:

Since Rust 1.36, this is now the HashMap implementation for the Rust standard library. However you may still want to use this crate instead since it works in environments without std, such as embedded systems and kernels.

However, it's unclear whether Rust std also uses ahash as the default hasher. If not, it seems like hashbrown would still be a better choice when it comes to performance.

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Additional context

Follow up from #676 (comment).

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