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Showing posts with the label solr

Resolving Lock Contention in Apache Solr: A Performance-Analysis Detective Story

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This case study is an instructive example of how performance analysis is a multi-faceted process that often leads one in surprising directions.  Apache Solr Near Real Time (NRT)  Search  allows Solr users to search documents indexed just seconds ago. It’s a critical feature in many real-time analytics applications. As Solr indexes more and more documents in near real time, end-user expectations for performance get higher and higher. However, recently the  Cloudera Search  team found that Solr NRT indexing throughput often hit a bottleneck even when there are plenty of CPU, disk, and network resources available. Latency was average, in the hundreds of milliseconds range. Considering that Solr NRT indexing is a mainly machine-to-machine operation, without a human waiting for indexing to complete, that latency range was actually fairly good. Furthermore, some customers reported other issues under heavy Solr NRT indexing workloads, such as connection resets,...

How-to: Index Scanned PDFs at Scale Using Fewer Than 50 Lines of Code

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Learn how to use OCR tools, Apache Spark, and other Apache Hadoop components to process PDF images at scale. Optical character recognition (OCR) technologies have advanced significantly over the last 20 years. However, during that time, there has been little or no effort to marry OCR with distributed architectures such as Apache Hadoop to process large numbers of images in near-real time. In this post, you will learn how to use standard open source tools along with Hadoop components such as Apache Spark, Apache Solr, and Apache HBase to do just that for a medical device information use case. Specifically, you will use a public  dataset  to convert narrative text into searchable fields. Although this example concentrates on medical device information, it can be applied in many other scenarios where processing and persisting images is required. Insurance companies, for example, can make all their scanned documents in claims files searchable for better claim resolu...

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