diff --git a/core/src/main/scala/org/apache/spark/network/netty/ShuffleSender.scala b/core/src/main/scala/org/apache/spark/network/netty/ShuffleSender.scala index 537f225469a8df772886ea315365e05e810726f2..8afcbe190a31cddd66d75f0a9fae901e38f3018b 100644 --- a/core/src/main/scala/org/apache/spark/network/netty/ShuffleSender.scala +++ b/core/src/main/scala/org/apache/spark/network/netty/ShuffleSender.scala @@ -20,6 +20,7 @@ package org.apache.spark.network.netty import java.io.File import org.apache.spark.Logging +import org.apache.spark.util.Utils private[spark] class ShuffleSender(portIn: Int, val pResolver: PathResolver) extends Logging { @@ -57,7 +58,7 @@ private[spark] object ShuffleSender { throw new Exception("Block " + blockId + " is not a shuffle block") } // Figure out which local directory it hashes to, and which subdirectory in that - val hash = math.abs(blockId.hashCode) + val hash = Utils.nonNegativeHash(blockId) val dirId = hash % localDirs.length val subDirId = (hash / localDirs.length) % subDirsPerLocalDir val subDir = new File(localDirs(dirId), "%02x".format(subDirId)) diff --git a/core/src/main/scala/org/apache/spark/storage/DiskStore.scala b/core/src/main/scala/org/apache/spark/storage/DiskStore.scala index fc25ef0fae2c9533b82b6c0fb1054ca6e71d3d16..63447baf8c6b402d3cd8afaf8bedcd7eabc27916 100644 --- a/core/src/main/scala/org/apache/spark/storage/DiskStore.scala +++ b/core/src/main/scala/org/apache/spark/storage/DiskStore.scala @@ -238,7 +238,7 @@ private class DiskStore(blockManager: BlockManager, rootDirs: String) logDebug("Getting file for block " + blockId) // Figure out which local directory it hashes to, and which subdirectory in that - val hash = math.abs(blockId.hashCode) + val hash = Utils.nonNegativeHash(blockId) val dirId = hash % localDirs.length val subDirId = (hash / localDirs.length) % subDirsPerLocalDir diff --git a/core/src/main/scala/org/apache/spark/util/Utils.scala b/core/src/main/scala/org/apache/spark/util/Utils.scala index 468800b2bd474341893da92d6a21d870a132153b..b890be2f6fa675c0385cbfd018b37abc19206e33 100644 --- a/core/src/main/scala/org/apache/spark/util/Utils.scala +++ b/core/src/main/scala/org/apache/spark/util/Utils.scala @@ -778,4 +778,18 @@ private[spark] object Utils extends Logging { val rawMod = x % mod rawMod + (if (rawMod < 0) mod else 0) } + + // Handles idiosyncracies with hash (add more as required) + def nonNegativeHash(obj: AnyRef): Int = { + + // Required ? + if (obj eq null) return 0 + + val hash = obj.hashCode + // math.abs fails for Int.MinValue + val hashAbs = if (Int.MinValue != hash) math.abs(hash) else 0 + + // Nothing else to guard against ? + hashAbs + } }