Java Slice

Last year in the investigation of a lot of java applications, see some of the phenomenon is the programmer to run on their own environment to read the program rarely lead to troubleshooting problems will be more frustrating, so think of writing this series of articles, procedures To provide functionality to end-users, the code is only one part of it, and it needs to be relied on for jvm, os, server hardware, networking, load balancing, etc. In this series of articles, Several parts, more is only a science role, because os I use are linux, this series ...

Multithreading is the problem that programmers often face in the interview, the level of mastery and understanding of multithreading concept is often used to measure a person's programming strength. Yes, ordinary multithreading is not easy, then when multithreading encounter "elephants" will produce what kind of sparks? 　　Here we share the Java thread Pool management and distributed Hadoop scheduling framework with 严澜, the Shanghai Creative Technology director. Usually the development of the thread is a thing, such as Tomcat in the servlet is the threads, no thread how we provide more ...

Usually the development of the thread is a thing, such as Tomcat is a servlet in the threads, there is no thread how do we provide multi-user access? But many developers who have just started to touch threads have suffered a lot. 　　How to do a set of simple threading Development Mode framework for everyone from the single thread development into multithreaded development, this is really a relatively difficult project. What is the specific thread? First look at what the process is, the process is a system executed a program, this program can use memory, processor, file system and other related resources ...

To use Hadoop, data consolidation is critical and hbase is widely used. In general, you need to transfer data from existing types of databases or data files to HBase for different scenario patterns. The common approach is to use the Put method in the HBase API, to use the HBase Bulk Load tool, and to use a custom mapreduce job. The book "HBase Administration Cookbook" has a detailed description of these three ways, by Imp ...

Spark can read and write data directly to HDFS and also supports Spark on YARN. Spark runs in the same cluster as MapReduce, shares storage resources and calculations, borrows Hive from the data warehouse Shark implementation, and is almost completely compatible with Hive. Spark's core concepts 1, Resilient Distributed Dataset (RDD) flexible distribution data set RDD is ...

The cloud infrastructure, such as Amazon EC2, has proven its value worldwide, and its ease of scaling, out-of-the-way, on-time billing, and so on, has freed developer creativity more thoroughly, but don't overlook the virtualized environment that was once considered a performance killer for applications and databases. Despite the performance aspect, cloud vendors have been looking for ways to improve, but as users of us, our own performance optimization tools are also essential. On the entity server, Aerospike has shown the peak of the million TPS, and now we are dedicated to improving the performance of cloud applications ...

How to install Nutch and Hadoop to search for Web pages and mailing lists, there seem to be few articles on how to install Nutch using Hadoop (formerly DNFs) Distributed File Systems (HDFS) and MapReduce. The purpose of this tutorial is to explain how to run Nutch on a multi-node Hadoop file system, including the ability to index (crawl) and search for multiple machines, step-by-step. This document does not involve Nutch or Hadoop architecture. It just tells how to get the system ...

At the same time support scheduling memory and CPU resources (default only supports memory, if you want to further scheduling the CPU, you need to make some configuration), this article describes how Hadoop YARN scheduling and isolation of these resources. In YARN, resource management is done jointly by the ResourceManager and the NodeManager, where the scheduler in the ResourceManager is responsible for allocating resources and NodeManager is responsible for providing and isolating resources. ResourceM ...

MapReduce is a programming model for parallel computing of large-scale data sets (greater than 1TB) to solve the computational problems of massive data.

MongoDB company formerly known as 10gen, founded in 2007, in 2013 received a sum of 231 million U.S. dollars in financing, the company's market value has been increased to 1 billion U.S. dollar level, this height is well-known open source company Red Hat (founded in 1993) 20 's struggle results. High-performance, easy to expand has been the foothold of the MongoDB, while the specification of documents and interfaces to make it more popular with users, this point from the analysis of the results of Db-engines's score is not difficult to see-just 1 years, MongoDB finished the 7th ...