how can we prioritize pods and preempt them

Question

Is there a way to prioritize and preempt the pods in kubernetes? How can i achieve this?

Answer 1

• A PriorityClass is a non-namespaced object that defines a mapping from a priority class name to the integer value of the priority. 

• The name is specified in the name field of the PriorityClass object’s metadata. The value is specified in the required value field. The higher the value, the higher the priority.

• A PriorityClass object can have any 32-bit integer value smaller than or equal to 1 billion. 

• Larger numbers are reserved for critical system Pods that should not normally be preempted or evicted. 

• A cluster admin should create one PriorityClass object for each such mapping that they want.

• PriorityClass also has two optional fields: globalDefault and description. 

• The globalDefault field indicates that the value of this PriorityClass should be used for Pods without a priorityClassName. 

• Only one PriorityClass with globalDefault set to true can exist in the system. 

• If there is no PriorityClass with globalDefault set, the priority of Pods with no priorityClassName is zero.