我做了个实验：
1、先创建一个pv，大小1Gi

apiVersion: v1
kind: PersistentVolume
metadata:
 name: nfs-pv01
 namespace: test
 labels:
  pv: nfs-pv01
spec:
 persistentVolumeReclaimPolicy: Recycle
 capacity:
  storage: 1Gi    # 指定pv大小
 accessModes:
  - ReadWriteMany
 nfs:
  server: 192.168.2.53
  path: /nfs_data/test

root@k8s-master1:~/AllYamls/pv_pvc# kubectl get pv
NAME         CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS      CLAIM                   STORAGECLASS   REASON   AGE
nfs-pv01     1Gi        RWX            Recycle          Available                                                   5s

2、创建两个pvc，大小都是100Mi

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
 name: nfs-pvc02  只修改这个地方
 namespace: test
spec:
 resources:
  requests:
   storage: 100Mi
  limits:
   storage: 100Mi
 accessModes:
  - ReadWriteMany
 selector:
  matchLabels:
   pv: nfs-pv01

结果发现只有一个pvc和pv绑定了

root@k8s-master1:~/AllYamls/pv_pvc# kubectl get pvc -n test
NAME        STATUS    VOLUME     CAPACITY   ACCESS MODES   STORAGECLASS   AGE
nfs-pvc01   Bound     nfs-pv01   1Gi        RWX                           4m24s
nfs-pvc02   Pending                                                       4m

root@k8s-master1:~/AllYamls/pv_pvc# kubectl get pv
NAME         CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS     CLAIM                   STORAGECLASS   REASON   AGE
nfs-pv01     1Gi        RWX            Recycle          Bound      test/nfs-pvc01                                  5m15s

从上面的pvc结果来看，虽然申请pvc的时候限制100Mi，但是从结果上看 nfs-pvc01的CAPACITY字段的值是1Gi。好像那个限制并没有起作用。
是不是nfs-pvc01这pvc实际大小还是1Gi，导致第二个pvc没法挂载成功