wirybeaver commented on PR #22947: URL: https://github.com/apache/datafusion/pull/22947#issuecomment-4713675339
One tradeoff worth making explicit: the previous whole-input model may still be the fastest path for small/medium inputs when memory is sufficient, because it concatenates once, evaluates over larger contiguous batches, and emits fewer output batches. This PR optimizes for a different failure mode: large/skewed inputs and memory-limited execution. If we want to preserve the existing fully in-memory fast path, one possible design is to keep the current `WindowAggExec` behavior and introduce a separate `SpillingWindowAggExec`, selected by the planner/config when spill support is desired. I am also open to exploring whether the spill/streaming work should be integrated with `BoundedWindowAggExec`, especially for bounded frames as mentioned in #22946. My hesitation is that `BoundedWindowAggExec` already has a specialized in-memory state/pruning model, so disk-backed state there likely deserves a separate focused design rather than being mixed into this PR. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
