Tag Archives: spark

Demystifying Spark Jobs to Optimize for Cost and Performance

Categories: Performance Spark

Apache Spark is one of the most popular engines for distributed data processing on Big Data clusters. Spark jobs come in all shapes, sizes and cluster form factors. Ranging from 10’s to 1000’s of nodes and executors, seconds to hours or even days for job duration, megabytes to petabytes of data and simple data scans to complicated analytical workloads. Throw in a growing number of streaming workloads to huge body of batch and machine learning jobs —

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Faster Performance for Selective Queries

Categories: CDH Impala

One of the principal features used in analytic databases is table partitioning. This feature is so frequently used because of its ability to significantly reduce query latency by allowing the execution engine to skip reading data that is not necessary for the query. For example, consider a table of events partitioned on the event time using calendar day granularity. If the table contained 2 years of events and a user wanted to find the events for a given 7-day window,

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Hadoop Delegation Tokens Explained

Categories: CDH Hadoop HDFS Platform Security & Cybersecurity

Apache Hadoop’s security was designed and implemented around 2009, and has been stabilizing since then. However, due to a lack of documentation around this area, it’s hard to understand or debug when problems arise. Delegation tokens were designed and are widely used in the Hadoop ecosystem as an authentication method. This blog post introduces the concept of Hadoop Delegation Tokens in the context of Hadoop Distributed File System (HDFS) and Hadoop Key Management Server (KMS),

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