How to choose the number oftopics/partitions in a Kafka cluster? 如何为一个kafka集群选择topics/partitions的数量? This is a common question asked by many Kafka users.The goal of this post is to explain a few important determining factors andprovide a few simple f…

This is a common question asked by many Kafka users. The goal of this post is to explain a few important determining factors and provide a few simple formulas. More Partitions Lead to Higher Throughput The first thing to understand is that a topic pa…

转自:http://blog.csdn.net/stark_summer/article/details/50203133 上一篇文章介绍了Kafka在设计上是如何来保证高时效.大吞吐量的,主要的内容集中在底层原理和架构上,属于理论知识范畴.这次我们站在应用和运维的角度,聊一聊集群到位后要怎么才能最好的配置参数和进行测试性能.Kafka的配置详尽且复杂,想要进行全面的性能调优需要掌握大量信息,我也只是通过工作中的一些实战经验来筛选出对集群性能影响最大的几个要点,接下来要阐述的观点也仅限于我所描述…

15.如何消费内部topic: __consumer_offsets 主要是要让它来格式化:GroupMetadataManager.OffsetsMessageFormatter 最后用看了它的源码,把这部分挑选出来,自己解析了得到的byte[].核心代码如下: // com.sina.mis.app.ConsumerInnerTopic ConsumerRecords<byte[], byte[]> records = consumer.poll(512); for (ConsumerRe…

kafka topic的制定,我们要考虑的问题有很多,比如生产环境中用几备份.partition数目多少合适.用几台机器支撑数据量,这些方面如何去考量?笔者根据实际的维护经验,写一些思考,希望大家指正. 1.replicas数目 可以从上图看到,备份越多,性能越低,因为kafka的写入只写入主分区,备份相当于消费者从主分区pull数据,这样势必会造成性能的损耗,故建议在生产环境中使用一主一备即可. 2. partition数量 (1)设置partition数量的时候我们需要注意:kafka的pa…

简述 在搭建HyperLedger Fabric环境的过程中,我们会用到一个configtx.yaml文件(可参考Hyperledger Fabric 1.0 从零开始(八)--Fabric多节点集群生产部署),该配置文件主要用于构建创世区块(在构建创世区块之前需要先创建与之对应的所有节点的验证文件集合),其中在配置Orderer信息中有一个OrdererType参数,该参数可配置为"solo" and "kafka",之前博文所讲的环境配置皆是solo,即单节点共…

简述 在搭建HyperLedger Fabric环境的过程中,我们会用到一个configtx.yaml文件(可参考Hyperledger Fabric 1.0 从零开始(八)——Fabric多节点集群生产部署),该配置文件主要用于构建创世区块(在构建创世区块之前需要先创建与之对应的所有节点的验证文件集合),其中在配置Orderer信息中有一个OrdererType参数,该参数可配置为"solo" and "kafka",之前博文所讲的环境配置皆是solo,即单节点共…

From the answer here, spark.sql.shuffle.partitions configures the number of partitions that are used when shuffling data for joins or aggregations. spark.default.parallelism is the default number of partitions in RDDs returned by transformations like…

Lucky Number Time Limit: 5000ms Memory Limit: 32768KB This problem will be judged on ZJU. Original ID: 323364-bit integer IO format: %lld      Java class name: Main   Watashi loves M mm very much. One day, M mm gives Watashi a chance to choose a numb…

From https://databricks.gitbooks.io/databricks-spark-knowledge-base/content/performance_optimization/how_many_partitions_does_an_rdd_have.html For tuning and troubleshooting, it's often necessary to know how many paritions an RDD represents. There ar…

Choosing number Time Limit: 2 Seconds      Memory Limit: 65536 KB There are n people standing in a row. And There are m numbers, 1.2...m. Every one should choose a number. But if two persons standing adjacent to each other choose the same number, the…

在关于spark任务并行度的设置中,有两个参数我们会经常遇到,spark.sql.shuffle.partitions 和 spark.default.parallelism, 那么这两个参数到底有什么区别的? 首先,让我们来看下它们的定义 Property Name Default Meaning spark.sql.shuffle.partitions 200 Configures the number of partitions to use when shuffling data for…

题目如下: Given a matrix consisting of 0s and 1s, we may choose any number of columns in the matrix and flip every cell in that column.  Flipping a cell changes the value of that cell from 0 to 1 or from 1 to 0. Return the maximum number of rows that hav…

14 down vote It's the other way round. Number of mappers is decided based on the number of splits. In reality it is the job of InputFormat, which you are using, to create the splits. You do not have any idea about the number of mappers until number o…

RAC: Frequently Asked Questions [ID 220970.1]   修改时间 13-JAN-2011     类型 FAQ     状态 PUBLISHED   Applies to: Oracle Server - Enterprise Edition - Version: 9.2.0.1 to 11.2.0.1 - Release: 9.2 to 11.2 Purpose Frequently Asked Questions for Real Applicatio…

producer接口: /** * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this…

http://kafka.apache.org/protocol   具体的协议看原文,   Preliminaries Network Kafka uses a binary protocol over TCP. The protocol defines all apis as request response message pairs. All messages are size delimited and are made up of the following primitive ty…

2.1 Producer API We encourage all new development to use the new Java producer. This client is production tested and generally both faster and more fully featured than the previous Scala client. You can use this client by adding a dependency on the c…

#!/bin/bash # # ti processor sdk linux am335x evm /bin/create-sdcard.sh hacking # 说明: # 本文主要对TI的sdk中的create-sdcard.sh脚本进行解读,该文件只解读 # 前面一部分,后面一部分未解读,主要是因为后面的代码并不能获取到正确 # 的设备节点,于是不打算深入解读.其中学会到了tar中显示解压进度的写法, # 以及拷贝文件夹的显示当前拷贝数据的进度的方法. # # -- 深圳 南山平山村 曾剑…

Statistics in Hive Statistics in Hive Motivation Scope Table and Partition Statistics Column Statistics Top K Statistics Implementation Usage Configuration Variables Newly Created Tables Existing Tables Examples Current Status (JIRA) This document de…

Querying and Inserting Data Simple Query Partition Based Query Joins Aggregations Multi Table/File Inserts Dynamic-Partition Insert Inserting into Local Files Sampling Union All Array Operations Map (Associative Arrays) Operations Custom Map/Reduce S…

<?xml version="1.0"?> <?xml-stylesheet type="text/xsl" href="configuration.xsl"?> <!-- Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file dist…

kafka 0.7.2 中对log.dir的定义如下: log.dir none Specifies the root directory in which all log data is kept. 在kafka 0.8 中将log.dir 修改为 log.dirs,官方文档说明如下: log.dirs /tmp/kafka-logs A comma-separated list of one or more directories in which Kafka data is stored.…

排序,真的非常重要! RDD.scala(源码) 在其,没有罗列排序,不是说它不重要! 1.基础排序算法实战 2.二次排序算法实战 3.更高级别排序算法 4.排序算法内幕解密 1.基础排序算法实战 启动hdfs集群 spark@SparkSingleNode:/usr/local/hadoop/hadoop-2.6.0$ sbin/start-dfs.sh 启动spark集群 spark@SparkSingleNode:/usr/local/spark/spark-1.5.2-bin-hadoo…

Kafka is a distributed publish-subscribe messaging system. It was originally developed at LinkedIn and became an Apache project in July, 2011. Today, Kafka is used by LinkedIn, Twitter, and Square for applications including log aggregation, queuing,…

 本博文的主要内容有 .kafka的官网介绍 http://kafka.apache.org/ 来,用官网上的教程,快速入门. http://kafka.apache.org/documentation kafka的官网文档教程. The Producer API allows an application to publish a stream records to one or more Kafka topics. The Consumer API allows an application…

本博文内容: 1.基础Top N算法实战 2.分组Top N算法实战 3.排序算法RangePartitioner内幕解密 1.基础Top N算法实战 Top N是排序,Take是直接拿出几个元素,没排序. 新建 142573279145 从源码,来说话,take返回的是数组,不是RDD.而colletc需要的是RDD. /** * Return an array that contains all of the elements in this RDD. */def collect(): Ar…

200.Which operation requires that you create an auxiliary instance manually before executing the operation? (Choose all that apply.) A. Backup-based database duplication. B. Active database duplication. C. Tablespace point-in-time recovery. D. No ope…

 Programming with RDDs This chapter introduces Spark's core abstraction for working with data, the resilientdistributed dataset (RDD). An RDD is simply a distributed collection of elements. InSpark all work is expressed as either creating new RDDs, t…

Table of contents Table of contents Overview Introduction Use cases Manual setup Assumption Configuration Startup & test Principle Topic Distribution Producer Consumer Operation Adding topics Modifying topics Removing a topic Graceful shutdown Balanc…