Github user srowen commented on a diff in the pull request: https://github.com/apache/spark/pull/16196#discussion_r91373995 --- Diff: core/src/main/scala/org/apache/spark/util/SizeEstimator.scala --- @@ -89,7 +90,13 @@ object SizeEstimator extends Logging { // A cache of ClassInfo objects for each class // We use weakKeys to allow GC of dynamically created classes - private val classInfos = new MapMaker().weakKeys().makeMap[Class[_], ClassInfo]() + private val classInfos = new ThreadLocal[WeakHashMap[Class[_], ClassInfo]] { + override def initialValue(): java.util.WeakHashMap[Class[_], ClassInfo] = { --- End diff -- Nit: remove java.util, and 'return' below. "map" is better than "toReturn" This is going to expand the memory footprint, because redundant copies of this info will be maintained per thread. Is the contention that significant?
--- 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