Question : Which of the following schedular ensurs that certain users, groups, or production applications always get sufficient resources. When a queue contains waiting applications, it gets at least its minimum share
Correct Answer : Get Lastest Questions and Answer : Exp: In addition to providing fair sharing, the Fair scheduler allows guaranteed minimum shares to be assigned to queues, which is useful for ensuring that certain users, groups, or production applications always get sufficient resources. When a queue contains waiting applications, it gets at least its minimum share; in contrast, when the queue does not need its full guaranteed share, the excess is split between other running applications. To avoid a single user flooding the clusters with hundreds of jobs, the Fair scheduler can limit the number of running applications per user and per queue through the configurations file. Using this limit, user applications will wait in the queue until previously submitted jobs finish.
Question :
Select the correct statement for the Fair Scheduler
1. allows containers to request variable amounts of memory and schedules based on those requirements 2. If an application is given a container that it cannot use immediately due to a shortage of memory, it can reserve that container, and no other application can use it until the container is released. 3. Access Mostly Uused Products by 50000+ Subscribers 4. 1 and 2 5. 1 and 3
Correct Answer : Get Lastest Questions and Answer : The YARN Fair scheduler allows containers to request variable amounts of memory and schedules based on those requirements. Support for other resource specifications, such as type of CPU, is under development. To prevent multiple smaller memory applications from starving a single large memory application, a "reserved container" has been introduced. If an application is given a container that it cannot use immediately due to a shortage of memory, it can reserve that container, and no other application can use it until the container is released. The reserved container will wait until other local containers are released and then use this additional capacity (i.e., extra RAM) to complete the job. One reserved container is allowed per node, and each node may have only one reserved container. The total reserved memory amount is reported in the ResourceManager UI. A larger number means that it may take longer for new jobs to get space.
The Capacity scheduler works best when the workloads are well known, which helps in assigning the minimum capacity. For this scheduler to work most effectively, each queue should be assigned a minimal capacity that is less than the maximal expected workload. Within each queue, multiple applications are scheduled using hierarchical FIFO queues similar to the approach used with the stand-alone FIFO scheduler.
Question : What is distributed cache? 1. The distributed cache is special component on namenode that will cache frequently used data for faster client response. It is used during reduce step 2. The distributed cache is special component on datanode that will cache frequently used data for faster client response. It is used during map step 3. Access Mostly Uused Products by 50000+ Subscribers 4. The distributed cache is a component that allows developers to deploy jars for Map-Reduce processing.