NiFi Processors currently have no means to relay whether or not they have may be resource intensive or not. The idea here would be to introduce an Annotation that can be added to Processors that indicate they may cause high memory, disk, CPU, or network usage. For instance, any Processor that reads the FlowFile contents into memory (like many XML Processors for instance) may cause high memory usage. What ultimately determines if there is high memory/disk/cpu/network usage will depend on the FlowFiles being processed. With many of these components in the dataflow, it increases the risk of OutOfMemoryErrors and performance degradation.
The annotation should support one value from a fixed list of: CPU, Disk, Memory, Network. It should also allow the developer to provide a custom description of the scenario that the component would fall under the high usage category. The annotation should be able to be specified multiple times, for as many resources as it has the potential to be high usage.
By marking components with this new Annotation, we can update the generated Processor documentation to include this fact.