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8 Ways to Optimize AWS Glue Jobs in a Nutshell

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  Improving the performance of AWS Glue jobs involves several strategies that target different aspects of the ETL (Extract, Transform, Load) process. Here are some key practices. 1. Optimize Job Scripts Partitioning : Ensure your data is properly partitioned. Partitioning divides your data into manageable chunks, allowing parallel processing and reducing the amount of data scanned. Filtering : Apply pushdown predicates to filter data early in the ETL process, reducing the amount of data processed downstream. Compression : Use compressed file formats (e.g., Parquet, ORC) for your data sources and sinks. These formats not only reduce storage costs but also improve I/O performance. Optimize Transformations : Minimize the number of transformations and actions in your script. Combine transformations where possible and use DataFrame APIs which are optimized for performance. 2. Use Appropriate Data Formats Parquet and ORC : These columnar formats are efficient for storage and querying, signif
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How to Use Help Command in HDFS

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Sometimes as a Hadoop developer it is difficult to remember all the Hadoop commands. The HELP command useful to know the correct syntax.

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How to List all HDFS Commands

hadoop
hadoop fs   ==> Enter

This will list all Hadoop commands.

Help Command in HDFS

Hadoop commands are the flavor of UNIX. If you want to see each Command description, you can go for Hadoop help command. You can use the below command for help.

hadoop fs -hlep ls 

Deleting a File in Hadoop HDFS

The below command helps   how to delete a file from Hadop cluster.

hadoop fs -rm exmaple.txt

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