EmilyMatt opened a new issue, #19680: URL: https://github.com/apache/datafusion/issues/19680
### Is your feature request related to a problem or challenge? In streams like the ExternalSorter stream, and some agg streams, and I'm sure in many others, we only return pending from the await, essentially polling the child stream in a loop until it is consumed, if the child stream comes from a stream which will always yield Ready(such as a parquet reader which already fetched all its data), we will never relinquish control back to the executor. This may be performant in some cases, but will also be obtrusive to actual async behaviour in the future. ### Describe the solution you'd like We should investigate the performance impact of polling the child stream, if it returns Pending, return, if it returns Ready(Some()), insert the batch into the sorter, and return Pending, until the child stream returns Ready(None), then we can actually call the sort function, which will actually provide a stream of batches. This is just a concrete example for SortExec, but I'm sure there are many operators that do the same. This can prevent thread starvation in a lot of cases, as well as allow more optimal behaviour should we every become fully async. ### Describe alternatives you've considered _No response_ ### Additional context _No response_ -- 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]
