HDFS native implementation of default RS codec leverages Intel ISA-L library to improve the encoding and decoding calculation. To enable and use Intel ISA-L, there are three steps.
1. Build ISA-L library. Please refer to the official site "https://github.com/01org/isa-l/" for detail information.
2. Build Hadoop with ISA-L support. Please refer to "Intel ISA-L build options" section in "Build instructions for Hadoop" in (BUILDING.txt) in the source code.
3. Use `-Dbundle.isal` to copy the contents of the `isal.lib` directory into the final tar file. Deploy Hadoop with the tar file. Make sure ISA-L is available on HDFS clients and DataNodes.