Github user clockfly commented on a diff in the pull request: https://github.com/apache/spark/pull/14915#discussion_r77139596 --- Diff: sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/trees/TreeNode.scala --- @@ -617,7 +618,9 @@ abstract class TreeNode[BaseType <: TreeNode[BaseType]] extends Product { case s: String => JString(s) case u: UUID => JString(u.toString) case dt: DataType => dt.jsonValue - case m: Metadata => m.jsonValue + // SPARK-17356: In usage of mllib, Metadata may store a huge vector of data, transforming --- End diff -- Current implementation of toJSON recursively searches the Map and Seq, and try to convert every field to JSON. It is quite risky, since we don't know what data is stored in unknown Seq and Map, and it may easily trigger OOM if the Seq or Map is a huge object. Maybe we should disable converting "Seq" and Map?
--- 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