[bugfix] The Metrics module uses a non-existent variable self.rank (#445)

Author: sumingZero

examples/ucm_config_example.yaml

@@ -16,7 +16,8 @@ ucm_connectors:
 
 load_only_first_rank: false
 
-metrics_config_path: "/vllm-workspace/metrics_config.yaml"
+# Enable UCM metrics so they can be monitored online via Grafana and Prometheus.
+# metrics_config_path: "/workspace/unified-cache-management/examples/metrics/metrics_configs.yaml"
 
 # Sparse attention configuration
 # Format 1: Dictionary format (for methods like ESA, KvComp)

ucm/integration/vllm/ucm_connector.py

@@ -174,7 +174,7 @@ def __init__(self, vllm_config: "VllmConfig", role: KVConnectorRole):
         if self.metrics_config:
             self.stats_logger = UCMStatsLogger(
                 vllm_config.model_config.served_model_name,
-                self.rank,
+                self.global_rank,
                 self.metrics_config,
             )
             self.monitor = ucmmonitor.StatsMonitor.get_instance()