Add bucket space in grafana

deploy/monitoring/grafana/dashboards/s3-balance-dashboard.json

@@ -258,6 +258,65 @@
       ],
       "title": "操作延迟 (秒)",
       "type": "timeseries"
+    },
+    {
+      "datasource": "Prometheus",
+      "fieldConfig": {
+        "defaults": {
+          "color": {
+            "mode": "continuous-BlPu"
+          },
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "green",
+                "value": null
+              },
+              {
+                "color": "orange",
+                "value": 1073741824
+              },
+              {
+                "color": "red",
+                "value": 268435456
+              }
+            ]
+          },
+          "unit": "bytes"
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 8,
+        "w": 12,
+        "x": 12,
+        "y": 8
+      },
+      "id": 11,
+      "options": {
+        "colorMode": "value",
+        "graphMode": "none",
+        "justifyMode": "auto",
+        "orientation": "auto",
+        "reduceOptions": {
+          "calcs": [
+            "lastNotNull"
+          ],
+          "fields": "",
+          "values": false
+        },
+        "textMode": "auto"
+      },
+      "targets": [
+        {
+          "expr": "s3_balance_bucket_capacity_bytes - s3_balance_bucket_usage_bytes",
+          "legendFormat": "{{bucket}}",
+          "refId": "A"
+        }
+      ],
+      "title": "存储桶剩余容量",
+      "type": "stat"
     }
   ],
   "refresh": "5s",