Use Infinity single-field-multi-index (#11444)

### What problem does this PR solve?

Use Infinity single-field-multi-index

### Type of change

- [x] Refactoring
- [x] Performance Improvement

admin/server/admin_server.py

@@ -20,6 +20,7 @@ import logging
 import time
 import threading
 import traceback
+import faulthandler
 
 from flask import Flask
 from flask_login import LoginManager
@@ -37,6 +38,7 @@ from common.versions import get_ragflow_version
 stop_event = threading.Event()
 
 if __name__ == '__main__':
+    faulthandler.enable()
     init_root_logger("admin_service")
     logging.info(r"""
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