diff --git a/.DS_Store b/.DS_Store
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diff --git a/README.md b/README.md
index 1f939d1..ae1e909 100644
--- a/README.md
+++ b/README.md
@@ -35,9 +35,6 @@ git checkout v1.14.3  # 切换到tag为v1.14.3的版本
 
 
 ## Tips
-md文档已同步至github,welcome star:
-https://github.com/yinwenqin/kubeSourceCodeNote
-
 Kubernetes这一整个项目颇为庞大，一般情况下，如果熟悉kubernetes的应用，结合应用来理解源码的设计理念会容易许多，因此，对其应用不熟悉的朋友，不建议直接阅读源码。另外，目前处于边阅读代码边输出总结的阶段，如文中有误，请予以指正，非常感谢！
 
 在此立一个flag，源码干货总结笔记，至少做到周不断更！
diff --git a/scheduler/.DS_Store b/scheduler/.DS_Store
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diff --git a/scheduler/P3-Node筛选算法.md b/scheduler/P3-Node筛选算法.md
index f50e6f0..28038ac 100644
--- a/scheduler/P3-Node筛选算法.md
+++ b/scheduler/P3-Node筛选算法.md
@@ -10,7 +10,7 @@
 
 ## 正文
 
-Schedule()的核心是`findNodesThatFit()`方法 ,直接跳转过去:
+Schedule()的筛选算法核心是`findNodesThatFit()`方法 ,直接跳转过去:
 
 `pkg/scheduler/core/generic_scheduler.go:184` --> `pkg/scheduler/core/generic_scheduler.go:435`
 
diff --git a/scheduler/P4-Node优先级算法.md b/scheduler/P4-Node优先级算法.md
new file mode 100644
index 0000000..7b81e26
--- /dev/null
+++ b/scheduler/P4-Node优先级算法.md
@@ -0,0 +1,59 @@
+# P4-Node优先级算法
+
+## 前言
+
+在上一篇文档中，我们过了一遍node筛选算法：
+
+[p3-Node筛选算法](https://github.com/yinwenqin/kubeSourceCodeNote/blob/master/scheduler/P3-Node%E7%AD%9B%E9%80%89%E7%AE%97%E6%B3%95.md)
+
+按调度规则设计，对筛选出的node，选择优先级最高的作为最终的fit node。那么本篇承接上一篇，进入下一步，node优先级算法。
+
+
+
+## 正文
+
+同上一篇，回到`pkg/scheduler/core/generic_scheduler.go`中的`Schedule()`函数，`pkg/scheduler/core/generic_scheduler.go:184`:
+
+![](https://github.com/yinwenqin/kubeSourceCodeNote/blob/master/scheduler/image/p4/schedule.jpg)
+
+截图中有几处标注，metric相关的几行，是收集metric信息，用以提供给prometheus使用的，kubernetes的几个核心组件都有这个功能，以后如果读prometheus的源码，这个单独拎出来再讲。
+
+
+
+**PodAffinity**示例：
+
+```yaml
+apiVersion: v1
+kind: Pod
+metadata:
+  name: pod-a
+  namespace: default
+spec:
+  affinity:
+    podAffinity:
+      preferredDuringSchedulingIgnoredDuringExecution:
+      - podAffinityTerm:
+        weight: 100
+          labelSelector:
+            matchExpressions:
+            - key: like
+              operator: In
+              values:
+              - pod-a
+          topologyKey: kubernetes.io/hostname
+    podAntiAffinity:
+      preferredDuringSchedulingIgnoredDuringExecution:
+      - weight: 100
+        podAffinityTerm:
+          labelSelector:
+            matchExpressions:
+            - key: unlike
+              operator: In
+              values:
+              - pod-a
+          topologyKey: kubernetes.io/hostname          
+  containers:
+  - name: test
+    image: gcr.io/google_containers/pause:2.0
+```
+
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diff --git a/scheduler/image/p2/generricSchedule.jpg b/scheduler/image/p2/genericSchedule.jpg
similarity index 100%
rename from scheduler/image/p2/generricSchedule.jpg
rename to scheduler/image/p2/genericSchedule.jpg
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