Record query consumption into fe audit log. Its basic mode of work is as follows, one of instance of parent plan is responsible for accumulating sub plan's consumption and send to it's parent, BE coordinator will get total consumption because it's a single instance.
Help to locate big query when system overload, by checking consumptions of running parts of current all queries or specified one query. Its basic mode of work is as follows: firstly trigger BE to report RuntimeProfiles, and wait a moment. secondly caculate consumptions with RuntimeProfiles reported by BE. The consumptions supported by it are the cost of running ExecNode in query when call it.