I do not believe that there is currently a way to do this. Do you want it so that the node can run only 1 mapper at a time but the node can also run multiple reducers at the same time? Do you want it so that this particular application will only use that node for a single mapper, but other applications may also run mappers on the node?
The RM has no knowledge about mapper vs. reducer, but the AM has no knowledge about other applications so it may require modifications in multiple places. --Bobby Evans On 4/26/12 12:56 PM, "Radim Kolar" <h...@filez.com> wrote: Its possible to configure in YARN scheduling requirement to not run more than 1 mapper per node? Its not because of memory requirements. Who decides this kind of scheduling? ResourceManager or ApplicationManager?
