During my research in Hadoop applications, I found that three applications are so popular. The Hadoop main architecture is to process both formatted and unformatted data in lesser time with less expensive servers. Most of these concepts covered in good hadoop online training.
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OpenTSDB
One of the first real-time Hadoop applications was OpenTSDB – a common-purpose implementation of a distributed, scalable Time Series Database (TSDB) that supported storing, indexing, and serving metrics collected from computer systems (for example, network gear, operating systems, and applications) on a large scale. OpenTSDB then made this data easily accessible and graphable.
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