mapleFU commented on issue #39899: URL: https://github.com/apache/arrow/issues/39899#issuecomment-1924515647
> I found that I could add a call to WhenBuffered to wait for the data to fully buffer and now I meet the performance of the localfilesystem! Firstly I think `bool_reader->ReadBatch` is a bit dangerous for nullable values. This is unrelated to this issue but I think the caller should understanding the concept of rep-level and def-levels if using the ColumnReader api 3s is so slow, would you mind tell the io pattern you're using? Actually the best pattern is send all io (if memory is enough) and waiting for them to finished, and read the file( or split the request by row-groups) -- 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]
