The question
Can routing and selective replication balance skewed joins with less communication and lower completion time?
This is a proposed research direction. No novel algorithm, completed benchmark or performance gain is claimed.
Why it matters
Distributed query and processing engines could reduce stragglers on hot keys.
Search space
Heavy-key detection, selective replication, salting and routing policies.
What would count as progress?
- Exact join output with duplicate multiplicity
- network bytes
- runtime
- peak memory
- maximum worker load.
A useful result improves a measured trade-off against strong baselines on held-out workloads, with reproducible code and documented limitations.
Baselines and boundaries
Compare hash partitioning and available skew handling. Count sampling and replication overhead. Include output cardinality in the workload because hot keys on both sides can create inherently huge results.
Starting reference
Where you could contribute
Help define representative, legally shareable workloads; critique the correctness contract; implement baselines; propose candidates; or reproduce measurements. Negative results and failure cases are useful contributions.
A detailed research brief is being prepared. Access requests will become available when that brief and the request service are ready.