The amount of resources (virtual CPU cores and memory) of YARN containers is configurable before the start of the run of any application components. By setting these resources at runtime—instead of as part of the application code—you can remove the requirement for re-compiling, re-packaging, and redeploying of an application in order to simply change the resources used.
Note: Any resource specifications set directly in the application (such as shown in MapReduce and Resources) will be
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overridden as the runtime arguments take precedence.
Virtual CPU Cores and Memory
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