alamb opened a new issue, #18470: URL: https://github.com/apache/datafusion/issues/18470
### Is your feature request related to a problem or challenge? The current Parquet reader has the following pattern: 1. Do I/O to buffer data needed for row groups 2. Decode the data (make RecordBatches) 3. fetching IO for next row group 4. ... The issue is that this means that after the row group is finished, the CPU will then have to wait for IO before it can begin decoding the next row group. We could use the CPUs more efficiently if we overlapped IO and CPU more ### Describe the solution you'd like Prefetch the next row group (to start the IO) while actively reading the current group ### Describe alternatives you've considered I made a POC of this approach and it looks promising (improves performance locally for very short queries) - https://github.com/apache/datafusion/pull/18391 ### 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]
