OSDOCS-1038: Adding docs for new descheduler policy

modules/nodes-descheduler-about.adoc

@@ -13,6 +13,7 @@ You can benefit from descheduling running Pods in situations such as the followi
 * Pod and node affinity requirements, such as taints or labels, have changed and the original scheduling decisions are no longer appropriate for certain nodes.
 * Node failure requires Pods to be moved.
 * New nodes are added to clusters.
+* Pods have been restarted too many times.
 
 [IMPORTANT]
 ====

modules/nodes-descheduler-configuring-strategies.adoc

@@ -32,24 +32,31 @@ spec:
   strategies:
     - name: "LowNodeUtilization" <1>
       params:
-       - name: "cputhreshold"
+       - name: "CPUThreshold"
          value: "10"
-       - name: "memorythreshold"
+       - name: "MemoryThreshold"
          value: "20"
-       - name: "podsthreshold"
+       - name: "PodsThreshold"
          value: "30"
-       - name: "memorytargetthreshold"
+       - name: "MemoryTargetThreshold"
          value: "40"
-       - name: "cputargetthreshold"
+       - name: "CPUTargetThreshold"
          value: "50"
-       - name: "podstargetthreshold"
+       - name: "PodsTargetThreshold"
          value: "60"
-       - name: "nodes"
+       - name: "NumberOfNodes"
          value: "3"
     - name: "RemoveDuplicates" <2>
+    - name: "RemovePodsHavingTooManyRestarts" <3>
+      params:
+       - name: "PodRestartThreshold"
+         value: "10"
+       - name: "IncludingInitContainers"
+         value: "false"
 ----
-<1> The `LowNodeUtilization` strategy provides additional parameters, such as `cputhreshold` and `memorythreshold`, that you can optionally configure.
+<1> The `LowNodeUtilization` strategy provides additional parameters, such as `CPUThreshold` and `MemoryThreshold`, that you can optionally configure.
 <2> The `RemoveDuplicates`, `RemovePodsViolatingInterPodAntiAffinity`, `RemovePodsViolatingNodeAffinity`, and `RemovePodsViolatingNodeTaints` strategies do not have any additional parameters to configure.
+<3> The `RemovePodsHavingTooManyRestarts` strategy requires the `PodRestartThreshold` parameter to be set. It also provides the optional `IncludingInitContainers` parameter.
 +
 You can enable multiple strategies and the order that the strategies are specified in is not important.
 

modules/nodes-descheduler-strategies.adoc

@@ -14,7 +14,7 @@ The underutilization of nodes is determined by several configurable threshold pa
 +
 You can also set a target threshold for CPU, memory, and number of Pods. If a node's usage is above the configured target thresholds for all parameters, then the node's Pods might be considered for eviction.
 +
-Additionally, you can use the `nodes` parameter to set the strategy to activate only when the number of underutilized nodes is above the configured value. This can be helpful in large clusters where a few nodes might be underutilized frequently or for a short period of time.
+Additionally, you can use the `NumberOfNodes` parameter to set the strategy to activate only when the number of underutilized nodes is above the configured value. This can be helpful in large clusters where a few nodes might be underutilized frequently or for a short period of time.
 
 Duplicate Pods::
 The `RemoveDuplicates` strategy ensures that there is only one Pod associated with a ReplicaSet, ReplicationController, Deployment, or Job running on same node. If there are more, then those duplicate Pods are evicted for better spreading of Pods in a cluster.
@@ -35,3 +35,10 @@ Violation of node taints::
 The `RemovePodsViolatingNodeTaints` strategy ensures that Pods violating `NoSchedule` taints on nodes are removed.
 +
 This situation could occur if a Pod is set to tolerate a taint `key=value:NoSchedule` and is running on a tainted node. If the node's taint is updated or removed, the taint is no longer satisfied by the Pod's tolerations and the Pod is evicted.
+
+Too many restarts::
+The `RemovePodsHavingTooManyRestarts` strategy ensures that Pods that have been restarted too many times are removed from nodes.
++
+This situation could occur if a Pod is scheduled on a node that is unable to start it. For example, if the node is having network issues and is unable to mount a networked persistent volume, then the Pod should be evicted so that it can be scheduled on another node. Another example is if the Pod is crashlooping.
++
+This strategy has two configurable parameters: `PodRestartThreshold` and `IncludingInitContainers`. If a Pod is restarted more than the configured `PodRestartThreshold` value, then the Pod is evicted. You can use the `IncludingInitContainers` parameter to specify whether restarts for Init Containers should be calculated into the `PodRestartThreshold` value.