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 this paper is to comb out the thread of
This time we start Spark-shell by specifying the Executor-memory parameter:The boot was successful.On the command line we have specified that the memory of executor on each machine Spark-shell run take up is 1g in size, and after successful launch see Web page:To read files from HDFs:The Mappedrdd returned in the command line, using todebugstring, can view its lineage relationship:You can see that Mappedrdd
The output from the WordCount in a previous article shows that the results are unsorted and how do you sort the output of spark?The result of Reducebykey is Key,value position permutation (number, character), then the number is sorted, and then the key,value position is replaced by the sorted result, and finally the result is stored in HDFsWe can find out that we have successfully sorted out the results!Spark
1. Spark is an open-source cluster computing system based on memory computing, which is designed to make data analysis faster. So the machine running spark should be as large as possible in memory, such as 96G or more.2. All operation of Spark is based on RDD, the operation is divided into 2 major categories: transformation and action.3.
In the conf file of your spark path, the CP copy Spark-defaults.conf.template is spark-defaults.conf
and add the following file
spark.eventLog.enabled trueSpark.eventLog.dir hdfs://master:9000/historySpark.eventLog.compress true
Distribute configuration to other child nodes I'm using rsync.
rsync sparkconf Path/spark
First, the foregoing
Spark resource Scheduling is a very important module, as long as the understanding of the principle, can specifically understand how spark is implemented, so particularly important.
In the case of voluntary application, this paper is divided into coarse grained and fine-grained models respectively.
second, the specific Spark Resource scheduli
Source: http://www.cnblogs.com/shishanyuan/p/4747735.html
1. Introduction to Spark streaming 1.1 Overview
Spark Streaming is an extension of the Spark core API that enables the processing of high-throughput, fault-tolerant real-time streaming data. Support for obtaining data from a variety of data sources, including KAFK, Flume, Twitter, ZeroMQ, Kinesis, and
Lesson One: A thorough understanding of sparkstreaming through cases kick: Decryption sparkstreaming alternative Experiment and sparkstreaming essence analysisThis issue guide:
1 Spark Source customization choose from sparkstreaming;
2 Spark streaming alternative online experiment;
3 instantly understand the essence of sparkstreaming.
1. Start Spar
absrtact: This article mainly introduces TalkingData in the process of building big data platform, introducing spark gradually, and build mobile big data platform based on Hadoop yarn and spark.Now, Spark has been widely recognized and supported at home: In 2014, spark Summit China in Beijing, the scene is hot, the same year,
ObjectiveIn the field of big data computing, Spark has become one of the increasingly popular and increasingly popular computing platforms. Spark's capabilities include offline batch processing in big data, SQL class processing, streaming/real-time computing, machine learning, graph computing, and many different types of computing operations, with a wide range of applications and prospects. In the mass reviews, many students have tried to use
class (according to the CLK. TSV Data Format)
Case class click (D: Java. util. Date, UUID: String, landing_page: INT)
// Load the file Reg. TSV on HDFS and convert each row of data to a register object;
Val Reg = SC. textfile ("HDFS: // chenx: 9000/week2/join/Reg. TSV "). map (_. split ("\ t ")). map (r => (r (1), register (format. parse (R (0), R (1), R (2), R (3 ). tofloat, R (4 ). tofloat )))
// Load the CLK. TSV file on HDFS and convert each row of data to a click object;
Val CLK = SC.
3, hands on the abstract class in ScalaThe definition of an abstract class requires the use of the abstract keyword:
The above code defines and implements the abstract method, it is important to note that we put the direct running code in the trait subclass of the app, about the inside of the app helps us implement the Main method and manages the code written by the engineer;Here's a look at the use of uninitialized variables in an abstract class:
4, hands-on trait in ScalaTrait
none, and below we look at the use of option:
Next, take a look at filter processing:
Here's a look at the zip operation for the collection:
Here's a look at the partition of the collection:
We can use flatten's multi-collection for flattening operations:
Flatmap is a combination of map and flatten operations, first map operation and then flatten operation:
"Spark Asia-Pacific Research ser
The collection mainly has list, set, Tuple, map, etc., we follow the hands-on practical way to learn. We create a list instance in the Eclipse IDE: Now let's look at the code implementation: In the source code, it is stated that the internal is the method of apply to complete the instantiation; In the same way we can instantiate set: You can also see the implementation of the set instantiation object at this point: Next we'll look at the set in the command-line terminal, first of all set:
5. Apply method and Singleton object in Scala to create a new class: As an additional point, the methods placed in object objects are static methods, as follows: Next look at the use of the Apply method: The above code always when we use "val a = Applytest ()" will cause the call of the Apply method and return the value of the method call, that is, the instantiated object of the applytest. C The lass can also be used by the Apply method, as shown in the following ways: Because the methods
Copy an object The content of the copied "input" folder is as follows: The content of the "conf" file under the hadoop installation directory is the same. Now, run the wordcount program in the pseudo-distributed mode we just built: After the operation is complete, let's check the output result: Some statistical results are as follows: At this time, we will go to the hadoop Web console and find that we have submitted and successfully run the task: After hadoop co
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 example, we can group, aggregate, or combine two o
Jobs that users submit through different threads can run concurrently, but are subject to resource constraints. Job to the dispatch pool (pool) To request resources, the dispatch pool will be based on the project configuration, decide which scheduling mode to use.
FIFO mode by default, the Spark Scheduler Dispatches job execution in FIFO (first-in first Out) mode. Each job is cut into multiple stage. The first job takes all available resources, and
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