NGA-TRAN commented on PR #18521: URL: https://github.com/apache/datafusion/pull/18521#issuecomment-3506608750
>>>> @2010YOUY01 : The second one is tpch-q4, I saw a 20% speedup in benchmark result, so I checked the query plan, and the difference is it's removing a round robin repartition above parquet reader: >>> @gene-bordegaray : Can you calrify the data you used to create the tables, thank you >> @NGA-TRAN : @2010YOUY01 : The reason Gene asked you to verify your test data is https://github.com/apache/datafusion/issues/18341#issuecomment-3505130845. It seems in the build side your lineitem table is too small to repartition. Thus the plan after the fix does not repartition it. That is the reason for the speedup > @gene-bordegaray: Yes, I am suspecting that i is due to the size of the tables because the logic for repartitioning at the file level lives above and independent of the repartitioning logic changes I have made That’s likely the case—there’s a predicate on the lineitem table, and we’ve pushed down a kind-of bloom filter to prune data during the scan. As a result, the dataset could be quite small. I wouldn’t worry about this scenario; it’s a reasonable outcome and one of the motivations behind the fix. Plus, it clearly improves query performance. -- 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]
