HDFS Architecture Overview
HDFS (Hadoop Distributed File System) architecture overview
- NameNode (nn): metadata storage file, and the block DataNodes other block list file name, directory structure, file attributes (generation time, number of copies, file permissions), as well as each file is located.
- DataNode (dn): file blocks stored in the local file system data, and a checksum data block.
- Secondary NameNode (2nn): used to monitor the status of auxiliary daemon HDFS, every once in a while get a snapshot of HDFS metadata.
Yarn Architecture Overview
MapReduce Architecture Overview
The MapReduce calculated two-stage process: Map and Reduce, as shown in FIG
. 1) Map the input stage of the parallel processing of data
2) Reduce the Map stage Summarizing
Big Data Technology Ecosystem
FIG involved in the technical terms are explained as follows:
- Sqoop: Sqoop is an open source tool, used mainly for inter Hadoop, Hive and traditional database (MySql) for transfer of data, a relational database may be (for example
: guide data MySQL, Oracle, etc.) into the Hadoop of HDFS, the HDFS data may be turned into a relational database.- Flume: Flume Cloudera is provided to a highly available, highly reliable, distributed massive log collection, aggregation and transmission system, The Flume all types of supports custom data sender log system for collecting data; Meanwhile, The Flume provide simple data processing, and the ability to write to party (customizable) various data accepted.
- Kafka：Kafka是一种高吞吐量的分布式发布订阅消息系统，有如下特性：
（1）通过O(1)的磁盘数据结构提供消息的持久化，这种结构对于即使数以TB的消息存储也能够保持长时间的稳定性能。
（2）高吞吐量：即使是非常普通的硬件Kafka也可以支持每秒数百万的消息。 （3）支持通过Kafka服务器和消费机集群来分区消息。（4）支持Hadoop并行数据加载。- Storm：Storm用于“连续计算”，对数据流做连续查询，在计算时就将结果以流的形式输出给用户。
- Spark：Spark是当前最流行的开源大数据内存计算框架。可以基于Hadoop上存储的大数据进行计算。
- Oozie：Oozie是一个管理Hdoop作业（job）的工作流程调度管理系统。
- Hbase：HBase是一个分布式的、面向列的开源数据库。HBase不同于一般的关系数据库，它是一个适合于非结构化数据存储的数据库。
- Hive：Hive是基于Hadoop的一个数据仓库工具，可以将结构化的数据文件映射为一张数据库表，并提供简单的SQL查询功能，可以将SQL语句转换为MapReduce任务进行运行。
其优点是学习成本低，可以通过类SQL语句快速实现简单的MapReduce统计，不必开发专门的MapReduce应用，十分适合数据仓库的统计分析。- R语言：R是用于统计分析、绘图的语言和操作环境。R是属于GNU系统的一个自由、免费、源代码开放的软件，它是一个用于统计计算和统计制图的优秀工具。
- Mahout：Apache Mahout是个可扩展的机器学习和数据挖掘库。
- ZooKeeper: Zookeeper Google's Chubby is an open source implementation. It is a reliable and harmonized system for large distributed systems, available features include: configuration maintenance, service name,
distributed synchronization, group services. ZooKeeper goal is to better encapsulate complex error-prone critical services, the easy to use interface and efficient performance, function and stability of the system to the user.
Framework for recommendation system
