YARN scheduler policies
As explained in the previous section, the ResourceManager acts as a pluggable global scheduler that manages and controls all the containers (resources). There are three different policies that can be applied over the scheduler, as per requirements and resource availability. They are as follows:
- The FIFO scheduler
- The Fair scheduler
- The Capacity scheduler
The FIFO (First In First Out) scheduler
FIFO means First In First Out. As the name indicates, the job submitted first will get priority to execute; in other words, the job runs in the order of submission. FIFO is a queue-based scheduler. It is a very simple approach to scheduling and it does not guarantee performance efficiency, as each job would use a whole cluster for execution. So other jobs may keep waiting to finish their execution, although a shared cluster has a great capability to offer more-than-enough resources to many users.
The fair scheduler
Fair scheduling is the policy of scheduling that assigns resources...
