2010YOUY01 commented on code in PR #15700: URL: https://github.com/apache/datafusion/pull/15700#discussion_r2046041614
########## datafusion/physical-plan/src/sorts/sort.rs: ########## @@ -431,12 +422,16 @@ impl ExternalSorter { let batches_to_spill = std::mem::take(globally_sorted_batches); self.reservation.free(); - let in_progress_file = self.in_progress_spill_file.as_mut().ok_or_else(|| { - internal_datafusion_err!("In-progress spill file should be initialized") - })?; + let (in_progress_file, max_record_batch_size) = + self.in_progress_spill_file.as_mut().ok_or_else(|| { + internal_datafusion_err!("In-progress spill file should be initialized") + })?; for batch in batches_to_spill { in_progress_file.append_batch(&batch)?; + + *max_record_batch_size = + (*max_record_batch_size).max(batch.get_actually_used_size()); Review Comment: I think we should not estimate, even if it's correct 99% of the time, IMO it's impossible to make sure it's always accurate for nested type's reader implementation. If the estimate is way off for edge cases, the bug would be hard to investigate. If we want to follow this optimistic approach, the only required memory accounting I think is during buffering batches inside `SortExec`, and all the remaining memory-tracking code can be deleted to make the implementation much more simpler, the potential problem is unexpected behavior for non-primitive types (e.g. dictionary array's row format size can explode) -- 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: github-unsubscr...@datafusion.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: github-unsubscr...@datafusion.apache.org For additional commands, e-mail: github-h...@datafusion.apache.org