跟我一塊兒數據挖掘（22）——spark入門

Spark簡介

Spark是UC Berkeley AMP lab所開源的類Hadoop MapReduce的通用的並行，Spark，擁有Hadoop MapReduce所具備的優勢；但不一樣於MapReduce的是Job中間輸出結果能夠保存在內存中，從而再也不須要讀寫HDFS，所以Spark能更好地適用於數據挖掘與機器學習等須要迭代的map reduce的算法。

Spark優勢

Spark是基於內存，是雲計算領域的繼Hadoop以後的下一代的最熱門的通用的並行計算框架開源項目，尤爲出色的支持Interactive Query、流計算、圖計算等。
Spark在機器學習方面有着無與倫比的優點，特別適合須要屢次迭代計算的算法。同時Spark的擁有很是出色的容錯和調度機制，確保系統的穩定運行，Spark目前的發展理念是經過一個計算框架集合SQL、Machine Learning、Graph Computing、Streaming Computing等多種功能於一個項目中，具備很是好的易用性。目前SPARK已經構建了本身的整個大數據處理生態系統，如流處理、圖技術、機器學習、NoSQL查詢等方面都有本身的技術，而且是Apache頂級Project，能夠預計的是2014年下半年在社區和商業應用上會有爆發式的增加。Spark最大的優點在於速度，在迭代處理計算方面比Hadoop快100倍以上；Spark另一個無可取代的優點是：「One Stack to rule them all」，Spark採用一個統一的技術堆棧解決了雲計算大數據的全部核心問題，這直接奠基了其一統雲計算大數據領域的霸主地位；

下圖是使用邏輯迴歸算法的使用時間：

Spark目前支持scala、python、JAVA編程。

做爲Spark的原生語言，scala是開發Spark應用程序的首選，其優雅簡潔的代碼，令開發過mapreduce代碼的碼農感受象是上了天堂。

能夠架構在hadoop之上，讀取hadoop、hbase數據。

spark的部署方式

一、standalone模式，即獨立模式，自帶完整的服務，可單獨部署到一個集羣中，無需依賴任何其餘資源管理系統。

二、Spark On Mesos模式。這是不少公司採用的模式，官方推薦這種模式（固然，緣由之一是血緣關係）。

三、Spark On YARN模式。這是一種最有前景的部署模式。

spark本機安裝

流程：進入linux->安裝JDK->安裝scala->安裝spark。

JDK的安裝和配置（略）。

安裝scala，進入http://www.scala-lang.org/download/下載。

下載後解壓縮。

tar zxvf scala-2.11.6.tgz 
//更名
mv scala-2.11.6 scala
//設置配置
export SCALA_HOME=/home/hadoop/software/scala
export PATH=$SCALA_HOME/bin;$PATH

source /etc/profile

scala -version
Scala code runner version 2.11.6 -- Copyright 2002-2013, LAMP/EPFL

scala設置成功。

從http://spark.apache.org/downloads.html下載spark並安裝。

下載後解壓縮。

進入$SPARK_HOME/bin，運行

./run-example SparkPi

運行結果

Spark assembly has been built with Hive, including Datanucleus jars on classpath
Using Spark's default log4j profile: org/apache/spark/log4j-defaults.properties
15/03/14 23:41:40 INFO SparkContext: Running Spark version 1.3.0
15/03/14 23:41:40 WARN Utils: Your hostname, localhost.localdomain resolves to a loopback address: 127.0.0.1; using 192.168.126.147 instead (on interface eth0)
15/03/14 23:41:40 WARN Utils: Set SPARK_LOCAL_IP if you need to bind to another address
15/03/14 23:41:41 WARN NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
15/03/14 23:41:41 INFO SecurityManager: Changing view acls to: hadoop
15/03/14 23:41:41 INFO SecurityManager: Changing modify acls to: hadoop
15/03/14 23:41:41 INFO SecurityManager: SecurityManager: authentication disabled; ui acls disabled; users with view permissions: Set(hadoop); users with modify permissions: Set(hadoop)
15/03/14 23:41:42 INFO Slf4jLogger: Slf4jLogger started
15/03/14 23:41:42 INFO Remoting: Starting remoting
15/03/14 23:41:42 INFO Remoting: Remoting started; listening on addresses :[akka.tcp://sparkDriver@192.168.126.147:60926]
15/03/14 23:41:42 INFO Utils: Successfully started service 'sparkDriver' on port 60926.
15/03/14 23:41:42 INFO SparkEnv: Registering MapOutputTracker
15/03/14 23:41:43 INFO SparkEnv: Registering BlockManagerMaster
15/03/14 23:41:43 INFO DiskBlockManager: Created local directory at /tmp/spark-285a6144-217c-442c-bfde-4b282378ac1e/blockmgr-f6cb0d15-d68d-4079-a0fe-9ec0bf8297a4
15/03/14 23:41:43 INFO MemoryStore: MemoryStore started with capacity 265.1 MB
15/03/14 23:41:43 INFO HttpFileServer: HTTP File server directory is /tmp/spark-96b3f754-9cad-4ef8-9da7-2a2c5029c42a/httpd-b28f3f6d-73f7-46d7-9078-7ba7ea84ca5b
15/03/14 23:41:43 INFO HttpServer: Starting HTTP Server
15/03/14 23:41:43 INFO Server: jetty-8.y.z-SNAPSHOT
15/03/14 23:41:43 INFO AbstractConnector: Started SocketConnector@0.0.0.0:42548
15/03/14 23:41:43 INFO Utils: Successfully started service 'HTTP file server' on port 42548.
15/03/14 23:41:43 INFO SparkEnv: Registering OutputCommitCoordinator
15/03/14 23:41:43 INFO Server: jetty-8.y.z-SNAPSHOT
15/03/14 23:41:43 INFO AbstractConnector: Started SelectChannelConnector@0.0.0.0:4040
15/03/14 23:41:43 INFO Utils: Successfully started service 'SparkUI' on port 4040.
15/03/14 23:41:43 INFO SparkUI: Started SparkUI at http://192.168.126.147:4040
15/03/14 23:41:44 INFO SparkContext: Added JAR file:/home/hadoop/software/spark-1.3.0-bin-hadoop2.4/lib/spark-examples-1.3.0-hadoop2.4.0.jar at http://192.168.126.147:42548/jars/spark-examples-1.3.0-hadoop2.4.0.jar with timestamp 1426347704488
15/03/14 23:41:44 INFO Executor: Starting executor ID <driver> on host localhost
15/03/14 23:41:44 INFO AkkaUtils: Connecting to HeartbeatReceiver: akka.tcp://sparkDriver@192.168.126.147:60926/user/HeartbeatReceiver
15/03/14 23:41:44 INFO NettyBlockTransferService: Server created on 39408
15/03/14 23:41:44 INFO BlockManagerMaster: Trying to register BlockManager
15/03/14 23:41:44 INFO BlockManagerMasterActor: Registering block manager localhost:39408 with 265.1 MB RAM, BlockManagerId(<driver>, localhost, 39408)
15/03/14 23:41:44 INFO BlockManagerMaster: Registered BlockManager
15/03/14 23:41:45 INFO SparkContext: Starting job: reduce at SparkPi.scala:35
15/03/14 23:41:45 INFO DAGScheduler: Got job 0 (reduce at SparkPi.scala:35) with 2 output partitions (allowLocal=false)
15/03/14 23:41:45 INFO DAGScheduler: Final stage: Stage 0(reduce at SparkPi.scala:35)
15/03/14 23:41:45 INFO DAGScheduler: Parents of final stage: List()
15/03/14 23:41:45 INFO DAGScheduler: Missing parents: List()
15/03/14 23:41:45 INFO DAGScheduler: Submitting Stage 0 (MapPartitionsRDD[1] at map at SparkPi.scala:31), which has no missing parents
15/03/14 23:41:45 INFO MemoryStore: ensureFreeSpace(1848) called with curMem=0, maxMem=278019440
15/03/14 23:41:45 INFO MemoryStore: Block broadcast_0 stored as values in memory (estimated size 1848.0 B, free 265.1 MB)
15/03/14 23:41:45 INFO MemoryStore: ensureFreeSpace(1296) called with curMem=1848, maxMem=278019440
15/03/14 23:41:45 INFO MemoryStore: Block broadcast_0_piece0 stored as bytes in memory (estimated size 1296.0 B, free 265.1 MB)
15/03/14 23:41:45 INFO BlockManagerInfo: Added broadcast_0_piece0 in memory on localhost:39408 (size: 1296.0 B, free: 265.1 MB)
15/03/14 23:41:45 INFO BlockManagerMaster: Updated info of block broadcast_0_piece0
15/03/14 23:41:45 INFO SparkContext: Created broadcast 0 from broadcast at DAGScheduler.scala:839
15/03/14 23:41:45 INFO DAGScheduler: Submitting 2 missing tasks from Stage 0 (MapPartitionsRDD[1] at map at SparkPi.scala:31)
15/03/14 23:41:45 INFO TaskSchedulerImpl: Adding task set 0.0 with 2 tasks
15/03/14 23:41:45 INFO TaskSetManager: Starting task 0.0 in stage 0.0 (TID 0, localhost, PROCESS_LOCAL, 1340 bytes)
15/03/14 23:41:45 INFO TaskSetManager: Starting task 1.0 in stage 0.0 (TID 1, localhost, PROCESS_LOCAL, 1340 bytes)
15/03/14 23:41:45 INFO Executor: Running task 1.0 in stage 0.0 (TID 1)
15/03/14 23:41:45 INFO Executor: Running task 0.0 in stage 0.0 (TID 0)
15/03/14 23:41:45 INFO Executor: Fetching http://192.168.126.147:42548/jars/spark-examples-1.3.0-hadoop2.4.0.jar with timestamp 1426347704488
15/03/14 23:41:45 INFO Utils: Fetching http://192.168.126.147:42548/jars/spark-examples-1.3.0-hadoop2.4.0.jar to /tmp/spark-db1e742b-020f-4db1-9ee3-f3e2d90e1bc2/userFiles-96c6db61-e95e-4f9e-a6c4-0db892583854/fetchFileTemp5600234414438914634.tmp
15/03/14 23:41:46 INFO Executor: Adding file:/tmp/spark-db1e742b-020f-4db1-9ee3-f3e2d90e1bc2/userFiles-96c6db61-e95e-4f9e-a6c4-0db892583854/spark-examples-1.3.0-hadoop2.4.0.jar to class loader
15/03/14 23:41:47 INFO Executor: Finished task 1.0 in stage 0.0 (TID 1). 736 bytes result sent to driver
15/03/14 23:41:47 INFO Executor: Finished task 0.0 in stage 0.0 (TID 0). 736 bytes result sent to driver
15/03/14 23:41:47 INFO TaskSetManager: Finished task 0.0 in stage 0.0 (TID 0) in 1560 ms on localhost (1/2)
15/03/14 23:41:47 INFO TaskSetManager: Finished task 1.0 in stage 0.0 (TID 1) in 1540 ms on localhost (2/2)
15/03/14 23:41:47 INFO TaskSchedulerImpl: Removed TaskSet 0.0, whose tasks have all completed, from pool 
15/03/14 23:41:47 INFO DAGScheduler: Stage 0 (reduce at SparkPi.scala:35) finished in 1.578 s
15/03/14 23:41:47 INFO DAGScheduler: Job 0 finished: reduce at SparkPi.scala:35, took 2.099817 s
Pi is roughly 3.14438
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/metrics/json,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/stages/stage/kill,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/static,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/executors/threadDump/json,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/executors/threadDump,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/executors/json,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/executors,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/environment/json,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/environment,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/storage/rdd/json,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/storage/rdd,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/storage/json,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/storage,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/stages/pool/json,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/stages/pool,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/stages/stage/json,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/stages/stage,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/stages/json,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/stages,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/jobs/job/json,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/jobs/job,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/jobs/json,null}
15/03/14 23:41:47 INFO ContextHandler: stopped o.s.j.s.ServletContextHandler{/jobs,null}
15/03/14 23:41:47 INFO SparkUI: Stopped Spark web UI at http://192.168.126.147:4040
15/03/14 23:41:47 INFO DAGScheduler: Stopping DAGScheduler
15/03/14 23:41:47 INFO MapOutputTrackerMasterActor: MapOutputTrackerActor stopped!
15/03/14 23:41:47 INFO MemoryStore: MemoryStore cleared
15/03/14 23:41:47 INFO BlockManager: BlockManager stopped
15/03/14 23:41:47 INFO BlockManagerMaster: BlockManagerMaster stopped
15/03/14 23:41:47 INFO OutputCommitCoordinator$OutputCommitCoordinatorActor: OutputCommitCoordinator stopped!
15/03/14 23:41:47 INFO SparkContext: Successfully stopped SparkContext
15/03/14 23:41:47 INFO RemoteActorRefProvider$RemotingTerminator: Shutting down remote daemon.
15/03/14 23:41:47 INFO RemoteActorRefProvider$RemotingTerminator: Remote daemon shut down; proceeding with flushing remote transports.

能夠看到輸出結果爲3.14438。