rayon-rs/rayon

idea: allow splitting that's weighted toward one side

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#477 opened on Nov 17, 2017

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 (3 comments) (0 reactions) (0 assignees)Rust (450 forks)batch import
enhancementhelp wanted

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Description

Usually we just split iterators at len/2. For something like find_first, it may be better to split closer to the front of the iterator, like len/3. Likewise, find_last might prefer something like 2 * len / 3.

For find_last, it might also be a good idea to flip the join arguments, so the latter split is processed first.

I'm not sure if these ideas could be exposed generically, or if the find functions should just implement custom bridge functions to this effect. Part of the challenge is that these are also at the end of the iterator chain, so their immediate input might not a Producer at all.

Contributor guide

Research direction
Investigate the current split implementation in Rayon's iterators, particularly the split method and bridge function. Understand how find first and find last use parallel iterators. Then propose a design for weighted splitting by modifying the producer trait or adding a custom bridge.
Tech stack
rust
Domain
backend
Issue type
Feature
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
RustRayon
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
60