Question : Select correct statements regarding ExpressLane features of MapR A. It allows small jobs to be executed before large jobs B. ExpressLane feature reserves one or more map or reduce slots on each task tracker C. If there is no slot available to run small job, it will be executed on "ephemeral slots" D. It requires to use fair scheduler E. If Small job is running on ephemeral slots and found to violet the definition of "small" , then job will be killed and re-scheduled as a normal job. 1. A,B,C 2. C,D,E 3. Access Mostly Uused Products by 50000+ Subscribers 4. A,B,E 5. A,B,C,D,E
Correct Answer : Get Lastest Questions and Answer : Explanation: MapR has made performance optimizations to the shuffle process, in which output from Mappers are sent to reducers. First, instead of writing intermediate data to local disks controlled by the operating system, MapR writes to a MapR-FS volume limited by its topology to the local node. This improves performance and reduces demand on local disk space while making the output available cluster-wide. The direct shuffle leverages the underlying storage layer and takes advantage of its unique capabilities: High sequential and random I/O performance, including the ability to create millions of files at extremely high rates (using sequential I/O) The ability to leverage multiple NICs via RPC-level bonding. By comparison, the shuffle in other distributions can only leverage a single NIC (in theory, one could use port trunking in any distribution, but the performance gains would be minimal compared to the MapR distribution s RPC-level load balancing) The ability to compress data at the block level
Question : How will MapR make sure, that maximum local volume is available for direct shuffle?
1. It reserve few nodes in the cluster and don t store or replicate data on these nodes
2. If there is more space required it delete the data replicated on this node and deleted data will be replicated on another node in cluster