Github user jkbradley commented on the pull request: https://github.com/apache/spark/pull/3702#issuecomment-67223829 Yep, that's what I meant. I think it would be extra code, but I don't think it would affect the runtime that much. (One pass to collect the number of elements in each partition should not take that long relative to the sortByKey.) Still, unless you're interested, I don't see a pressing need to make it exact. The simplistic approach should never be off by more than numPartitions. One intermediate option would be to oversample by a factor of 2 or 3 (up to the dataset size) and then choose the correct number of bins on the driver. The bins would be shifted by a tiny bit, but that sounds OK to me.
--- If your project is set up for it, you can reply to this email and have your reply appear on GitHub as well. If your project does not have this feature enabled and wishes so, or if the feature is enabled but not working, please contact infrastructure at infrastruct...@apache.org or file a JIRA ticket with INFRA. --- --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org