From 6042d717e9b3235ad8006ea5c83aa4f122726720 Mon Sep 17 00:00:00 2001
From: lixiang <lixiang.cdc@gmail.com>
Date: Thu, 24 Sep 2020 17:49:02 +0800
Subject: [PATCH 1/2] delete disabled strategies in podLifeTime use case

---
 docs/user-guide.md         | 12 ------------
 examples/pod-life-time.yml | 12 ------------
 2 files changed, 24 deletions(-)

diff --git a/docs/user-guide.md b/docs/user-guide.md
index bce12b5a3..9b6de91eb 100644
--- a/docs/user-guide.md
+++ b/docs/user-guide.md
@@ -69,18 +69,6 @@ This policy configuration file ensures that pods created more than 7 days ago ar
 apiVersion: "descheduler/v1alpha1"
 kind: "DeschedulerPolicy"
 strategies:
-  "LowNodeUtilization":
-    enabled: false
-  "RemoveDuplicates":
-    enabled: false
-  "RemovePodsViolatingInterPodAntiAffinity":
-    enabled: false
-  "RemovePodsViolatingNodeAffinity":
-    enabled: false
-  "RemovePodsViolatingNodeTaints":
-    enabled: false
-  "RemovePodsHavingTooManyRestarts":
-    enabled: false
   "PodLifeTime":
     enabled: true
     params:
diff --git a/examples/pod-life-time.yml b/examples/pod-life-time.yml
index 1bce94289..f078c3d1b 100644
--- a/examples/pod-life-time.yml
+++ b/examples/pod-life-time.yml
@@ -2,18 +2,6 @@
 apiVersion: "descheduler/v1alpha1"
 kind: "DeschedulerPolicy"
 strategies:
-  "LowNodeUtilization":
-    enabled: false
-  "RemoveDuplicates":
-    enabled: false
-  "RemovePodsViolatingInterPodAntiAffinity":
-    enabled: false
-  "RemovePodsViolatingNodeAffinity":
-    enabled: false
-  "RemovePodsViolatingNodeTaints":
-    enabled: false
-  "RemovePodsHavingTooManyRestarts":
-    enabled: false
   "PodLifeTime":
     enabled: true
     params:

From 00f79aa28d070ce75e3be8eba3cf2b9c5fe0db01 Mon Sep 17 00:00:00 2001
From: lixiang <lixiang.cdc@gmail.com>
Date: Thu, 24 Sep 2020 17:51:08 +0800
Subject: [PATCH 2/2] add use case for lowNodeUtilization

---
 docs/user-guide.md                | 23 +++++++++++++++++++++++
 examples/low-node-utilization.yml | 12 ++++++++++++
 2 files changed, 35 insertions(+)
 create mode 100644 examples/low-node-utilization.yml

diff --git a/docs/user-guide.md b/docs/user-guide.md
index 9b6de91eb..342d75cfe 100644
--- a/docs/user-guide.md
+++ b/docs/user-guide.md
@@ -75,6 +75,29 @@ strategies:
       maxPodLifeTimeSeconds: 604800 # pods run for a maximum of 7 days
 ```
 
+### Balance Cluster By Node Memory Utilization
+
+If your cluster has been running for a long period of time, you may find that the resource utilization is not very
+balanced. The `LowNodeUtilization` strategy can be used to rebalance your cluster based on `cpu`, `memory`
+or `number of pods`.
+
+Using the following policy configuration file, descheduler will rebalance the cluster based on memory by evicting pods
+from nodes with memory utilization over 70% to nodes with memory utilization below 20%.
+
+```
+apiVersion: "descheduler/v1alpha1"
+kind: "DeschedulerPolicy"
+strategies:
+  "LowNodeUtilization":
+    enabled: true
+    params:
+      nodeResourceUtilizationThresholds:
+        thresholds:
+          "memory": 20
+        targetThresholds:
+          "memory": 70
+```
+
 ### Autoheal Node Problems
 Descheduler's `RemovePodsViolatingNodeTaints` strategy can be combined with
 [Node Problem Detector](https://github.com/kubernetes/node-problem-detector/) and
diff --git a/examples/low-node-utilization.yml b/examples/low-node-utilization.yml
new file mode 100644
index 000000000..bd8d0613f
--- /dev/null
+++ b/examples/low-node-utilization.yml
@@ -0,0 +1,12 @@
+---
+apiVersion: "descheduler/v1alpha1"
+kind: "DeschedulerPolicy"
+strategies:
+  "LowNodeUtilization":
+    enabled: true
+    params:
+      nodeResourceUtilizationThresholds:
+        thresholds:
+          "memory": 20
+        targetThresholds:
+          "memory": 70