Apache Spark我在这里坚持什么? [英] Apache Spark what am I persisting here?

问题描述

在这一行中，哪个RDD被保留?dropResultsN或dataSetN?

In this line, which RDD is being persisted? dropResultsN or dataSetN?

dropResultsN = dataSetN.map(s -> standin.call(s)).persist(StorageLevel.MEMORY_ONLY());

问题来自>针对JavaRDD的每次操作的Apache Spark计时，我仍然在寻找如何最好地确定RDD创建时间的核心问题的好答案.

Question arises as a side issue from Apache Spark timing forEach operation on JavaRDD, where I am still looking for a good answer to the core question of how best to time RDD creation.

推荐答案

dropResultsN 是持久的RDD(它是通过将 dataSetN 映射到方法 standin.call()).

dropResultsN is the persisted RDD (which is the RDD produced by mapping dataSetN onto the method standin.call()).

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