Github user neggert commented on a diff in the pull request:
https://github.com/apache/spark/pull/14140#discussion_r70450795
--- Diff:
mllib/src/main/scala/org/apache/spark/mllib/regression/IsotonicRegression.scala
---
@@ -408,8 +409,12 @@ class IsotonicRegression private (private var
isotonic: Boolean) extends Seriali
*/
private def parallelPoolAdjacentViolators(
input: RDD[(Double, Double, Double)]): Array[(Double, Double,
Double)] = {
- val parallelStepResult = input
- .sortBy(x => (x._2, x._1))
+ val keyedInput = input
--- End diff --
`repartitionAndSortWithinPartitions` requires the partition key and the
sortBy key to be the same. We want to partition by feature, then sort by
feature *and* label. So it would still require a second step to sort the
partitions, although they'd be mostly sorted already. Maybe there could be a
speed-up by using an insertion or Timsort on the mostly-sorted partition...
---
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 [email protected] or file a JIRA ticket
with INFRA.
---
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
