apache spark explained

Resolution: Find the name between the ages of 13-19 years old. Summary: With the above steps, the Spark SQL basic operation is to first create sqlcontext and define the case class, and then through the transform process of the RDD, the case class is implicitly converted into Dataframe, Finally, the Dataframe is registered as a table in the SqlContext, so we can manipulate the table. Three. Spark SQL oper

Summary:RDD: Elastic distributed DataSet, is a special set of ' support multiple sources ' have fault tolerant mechanism ' can be cached ' support parallel operation, an Rdd represents a dataset in a partitionThere are two operators of Rdd: Transformation (conversion):transformation is a deferred calculation, when an RDD is converted to another RDD without immediate conversion, just remember the logical operation of the datasetAtion (execution): triggers the operation of the

The previous article "Apache Spark Learning: Deploying Spark to Hadoop 2.2.0" describes how to use MAVEN compilation to build spark jar packages that run directly on the Hadoop 2.2.0, and on this basis, Describes how to build an spark integrated development environment with

You are welcome to reprint it. Please indicate the source, huichiro.Wedge Hive is an open source data warehouse tool based on hadoop. It provides a hiveql language similar to SQL, this allows upper-layer data analysts to analyze massive data stored in HDFS without having to know too much about mapreduce. This feature has been widely welcomed. An important module in the overall hive framework is the execution module, which is implemented using the mapreduce computing framework in hadoop. Therefor

= Records.newRecord(ContainerLaunchContext.class); amContainer.setCommands( Collections.singletonList( "$JAVA_HOME/bin/java" + " -Xmx256M" + " com.hortonworks.simpleyarnapp.ApplicationMaster" + " " + command + " " + String.valueOf(n) + " 1>" + ApplicationConstants.LOG_DIR_EXPANSION_VAR + "/stdout" + " 2>" + ApplicationConstants.LOG_DIR_EXPANSION_VAR + "/stderr" ) ); However, the Class

Savetocassandra the stored procedure that triggered the data Another place worth documenting is that if the table created in Cassandra uses the UUID as primary key, use the following function in Scala to generate the UUIDimport java.util.UUIDUUID.randomUUIDVerification stepsUse Cqlsh to see if the data is actually written to the TEST.KV table.SummaryThis experiment combines the following knowledge Spark SQL

{case (key, value) = > value.tostring (). Split ("\\s+"); Map (Word = > (word, 1)). Reducebykey (_ + _) Where the Flatmap function converts a record into multiple records (One-to-many relationships), the map function converts a record to another record (one-to-one relationship), and the Reducebykey function divides the same data into a bucket and calculates it in key units. The specific meaning of these functions can be referred to: Spark transformati

http broadcast spark.broadcast.port jetty-based, Torrentbroadcast does not use this port, it sends data through the Block manager executor driver random spark.replclassserver.port jetty-based, Only for spark shell Executor/driver Executor/driver Random Block Manager Port Spark.blockManager.port Raw socket via Serversocketchannel

the source reading, we need to focus on the following two main lines. static View is RDD, transformation and action Dynamic View is the life of a job, each job is divided into multiple stages, each stage can contain more than one RDD and its transformation, How these stages are mapped into tasks is distributed into cluster References (Reference) Introduction to Spark Internals http://files.meetup.com/3138542/dev-meetup-dec-

documentation.SummaryIn the source reading, we need to focus on the following two main lines. static View is RDD, transformation and action Dynamic View is the life of a job, each job is divided into multiple stages, each stage can contain more than one RDD and its transformation, How these stages are mapped into tasks is distributed into cluster References (Reference) Introduction to Spark Internals http://files.meetup.com

will store intermediate results in the/tmp directory while computing, Linux now supports TMPFS, in fact, it is simply to mount the/tmp directory into memory.Then there is a problem, the middle result is too much cause the/tmp directory is full and the following error occurredNo Space left on the deviceThe workaround is to not enable TMPFS for the TMP directory, modify the/etc/fstabQuestion 2Sometimes you may encounter Java.lang.OutOfMemory, unable to create new native thread error, which causes

. Assume that you use git to synchronize the latest source code. git clone https://github.com/apache/spark.git Generate an idea Project sbt/sbt gen-idea Import Spark Source Code 1. Select File-> Import project and specify the Spark Source Code directory in the pop-up window. 2. Select SBT project as the project type and click Next 3. Click Finish in the new pop

Https://www.iteblog.com/archives/1624.html Whether we need another new data processing engine. I was very skeptical when I first heard of Flink. In the Big data field, there is no shortage of data processing frameworks, but no framework can fully meet the different processing requirements. Since the advent of Apache Spark, it seems to have become the best framework for solving most of the problems today, s

monitoring of computing resources, restarting failed tasks based on monitoring results, or re-distributed task once a new node joins cluster.This part of the content needs to refer to yarn's documentation.SummaryIn the source reading, we need to focus on the following two main lines. static View is RDD, transformation and action Dynamic View is the life of a job, each job is divided into multiple stages, each stage can contain more than one RDD and its transformation, How these sta

Summary: The advent of Apache Spark has made it possible for ordinary people to have big data and real-time data analysis capabilities. In view of this, this article through hands-on Operation demonstration to lead everyone to learn spark quickly. This article is the first part of a four-part tutorial on the Apache

You are welcome to reprint it. Please indicate the source, huichiro.Summary There is nothing to say about source code compilation. For Java projects, as long as Maven or ant simple commands are clicked, they will be OK. However, when it comes to spark, it seems that things are not so simple. According to the spark officical document, there will always be compilation errors in one way or another, which is an

, * * w‘ = w - thisIterStepSize * (gradient + regGradient(w)) * Note that regGradient is function of w * * If we set gradient = 0, thisIterStepSize = 1, then * * regGradient(w) = w - w‘ * * TODO: We need to clean it up by separating the logic of regularization out * from updater to regularizer. */ // The following gradientTotal is actually the regularization part of gradient. // Will add the gradientSum computed fr

This article, it is necessary to read, write well. But after looking, don't forget to check out the Apache Spark website. Because this article understanding or with the source code, official documents inconsistent. A little mistake! "The Cnblogs Code Editor does not support Scala, so the language keyword is not highlighted"In data analysis, processing Key,value pair data is a very common scenario, for examp

Apache Spark Memory Management detailedAs a memory-based distributed computing engine, Spark's memory management module plays a very important role in the whole system. Understanding the fundamentals of spark memory management helps to better develop spark applications and perform performance tuning. The purpose of thi

Spark Cluster Mode Overview Spark Sort Based Shuffle Memory Analysis Spark Off_heap Unified Memory Management in Spark 1.6 Tuning spark:garbage Collection Tuning Spark Architecture Spark