Github user pwendell commented on a diff in the pull request:
https://github.com/apache/spark/pull/126#discussion_r10581534
--- Diff:
core/src/main/scala/org/apache/spark/scheduler/ShuffleMapTask.scala ---
@@ -17,28 +17,24 @@
package org.apache.spark.scheduler
+import scala.collection.mutable.HashMap
+
import java.io._
import java.util.zip.{GZIPInputStream, GZIPOutputStream}
-import scala.collection.mutable.HashMap
-
import org.apache.spark._
import org.apache.spark.executor.ShuffleWriteMetrics
-import org.apache.spark.rdd.RDD
-import org.apache.spark.rdd.RDDCheckpointData
+import org.apache.spark.rdd.{RDD, RDDCheckpointData}
import org.apache.spark.storage._
-import org.apache.spark.util.{MetadataCleaner, MetadataCleanerType,
TimeStampedHashMap}
+import org.apache.spark.util.BoundedHashMap
private[spark] object ShuffleMapTask {
// A simple map between the stage id to the serialized byte array of a
task.
// Served as a cache for task serialization because serialization can be
// expensive on the master node if it needs to launch thousands of tasks.
- val serializedInfoCache = new TimeStampedHashMap[Int, Array[Byte]]
-
- // TODO: This object shouldn't have global variables
- val metadataCleaner = new MetadataCleaner(
- MetadataCleanerType.SHUFFLE_MAP_TASK,
serializedInfoCache.clearOldValues, new SparkConf)
+ val MAX_CACHE_SIZE = 100
+ val serializedInfoCache = new BoundedHashMap[Int,
Array[Byte]](MAX_CACHE_SIZE, true)
--- End diff --
@andrewor14 what I'm suggest is even simpler than that (for this specific
data structure). When the stage finishes, you can just remove the associated
entries in this hash map. Once a given stages finishes we will never re-execute
the a stage with the same stageId AFIAK. Maybe @markhamstra could confirm this.
The thing you are suggesting is needed (I think) but not for this
particular case where I believe something simpler will suffice.
---
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.
---
