unifies the config properties name prefix; add the configs into docs/configuration.md

Author: RongGu

core/src/main/scala/org/apache/spark/SparkContext.scala

@@ -129,7 +129,7 @@ class SparkContext(
   // Generate the random name for a temp folder in Tachyon
   // Add a timestamp as the suffix here to make it more safe
   val tachyonFolderName = "spark-" + randomUUID.toString()
-  conf.set("spark.tachyonstore.foldername", tachyonFolderName)
+  conf.set("spark.tachyonStore.folderName", tachyonFolderName)
 
   val isLocal = (master == "local" || master.startsWith("local["))
 

core/src/main/scala/org/apache/spark/storage/BlockManager.scala

@@ -59,10 +59,10 @@ private[spark] class BlockManager(
   private[storage] val diskStore = new DiskStore(this, diskBlockManager)
   var tachyonInitialized = false
   private[storage] lazy val tachyonStore: TachyonStore = {
-    val storeDir = conf.get("spark.tachyonstore.dir", System.getProperty("java.io.tmpdir"))
-    val appFolderName = conf.get("spark.tachyonstore.foldername")
+    val storeDir = conf.get("spark.tachyonStore.baseDir", System.getProperty("java.io.tmpdir"))
+    val appFolderName = conf.get("spark.tachyonStore.folderName")
     val tachyonStorePath = s"${storeDir}/${appFolderName}/${this.executorId}"
-    val tachyonMaster = conf.get("spark.tachyonmaster.address",  "tachyon://localhost:19998")
+    val tachyonMaster = conf.get("spark.tachyonStore.URL",  "tachyon://localhost:19998")
     val tachyonBlockManager = new TachyonBlockManager(
       shuffleBlockManager, tachyonStorePath, tachyonMaster)
     tachyonInitialized = true

core/src/main/scala/org/apache/spark/storage/TachyonBlockManager.scala

@@ -52,9 +52,9 @@ private[spark] class TachyonBlockManager(
   private val subDirsPerTachyonDir = 
     shuffleManager.conf.get("spark.tachyonStore.subDirectories", "64").toInt
 
-  // Create one Tachyon directory for each path mentioned in spark.tachyon.dir; then, inside this
-  // directory, create multiple subdirectories that we will hash files into, in order to avoid
-  // having really large inodes at the top level in Tachyon.
+  // Create one Tachyon directory for each path mentioned in spark.tachyonStore.folderName.dir; 
+  // then, inside this directory, create multiple subdirectories that we will hash files into, 
+  // in order to avoid having really large inodes at the top level in Tachyon.
   private val tachyonDirs: Array[TachyonFile] = createTachyonDirs()
   private val subDirs = Array.fill(tachyonDirs.length)(new Array[TachyonFile](subDirsPerTachyonDir))
 

docs/configuration.md

@@ -122,6 +122,21 @@ Apart from these, the following properties are also available, and may be useful
     <code>spark.storage.memoryFraction</code>.
   </td>
 </tr>
+<tr>
+  <td>spark.tachyonStore.baseDir</td>
+  <td>/tmp/</td>
+  <td>
+    Directories of the Tachyon File System that store RDDs. The Tachyon file system's URL is set by <code>spark.tachyonStore.URL</code>. 
+    It can also be a comma-separated list of multiple directories on Tachyon file system.
+  </td>
+</tr>
+<tr>
+  <td>spark.tachyonStore.URL</td>
+  <td>tachyon://localhost:19998</td>
+  <td>
+    The URL of the underlying Tachyon file system in the TachyonStore.
+  </td>
+</tr>
 <tr>
   <td>spark.mesos.coarse</td>
   <td>false</td>