Spark列出所有缓存的RDD名称，并且不持久

Question

我是Apache Spark的新手，我创建了几个RDD和DataFrame，并对其进行了缓存，现在我想使用以下命令取消持久化其中的一些

rddName.unpersist()

但我不记得他们的名字。我用过，sc.getPersistentRDDs但是输出不包含名称。我还使用浏览器查看了缓存的rdds，但再次没有名称信息。我想念什么吗？

Answer 1

@Dikei的答案实际上是正确的，但我相信您正在寻找的是sc.getPersistentRDDs：

scala> val rdd1 = sc.makeRDD(1 to 100)
# rdd1: org.apache.spark.rdd.RDD[Int] = ParallelCollectionRDD[0] at makeRDD at <console>:27

scala> val rdd2 = sc.makeRDD(10 to 1000)
# rdd2: org.apache.spark.rdd.RDD[Int] = ParallelCollectionRDD[1] at makeRDD at <console>:27

scala> rdd2.cache.setName("rdd_2")
# res0: rdd2.type = rdd_2 ParallelCollectionRDD[1] at makeRDD at <console>:27

scala> sc.getPersistentRDDs
# res1: scala.collection.Map[Int,org.apache.spark.rdd.RDD[_]] = Map(1 -> rdd_2 ParallelCollectionRDD[1] at makeRDD at <console>:27)

scala> rdd1.cache.setName("foo")
# res2: rdd1.type = foo ParallelCollectionRDD[0] at makeRDD at <console>:27

scala> sc.getPersistentRDDs
# res3: scala.collection.Map[Int,org.apache.spark.rdd.RDD[_]] = Map(1 -> rdd_2 ParallelCollectionRDD[1] at makeRDD at <console>:27, 0 -> foo ParallelCollectionRDD[0] at makeRDD at <console>:27)

现在让我们添加另一个RDD并命名它：

scala> rdd3.setName("bar")
# res4: rdd3.type = bar ParallelCollectionRDD[2] at makeRDD at <console>:27

scala> sc.getPersistentRDDs
# res5: scala.collection.Map[Int,org.apache.spark.rdd.RDD[_]] = Map(1 -> rdd_2 ParallelCollectionRDD[1] at makeRDD at <console>:27, 0 -> foo ParallelCollectionRDD[0] at makeRDD at <console>:27)

我们注意到它实际上并没有持久。