diff --git a/lightrag/kg/mongo_impl.py b/lightrag/kg/mongo_impl.py
index 61222357..fbbae8c2 100644
--- a/lightrag/kg/mongo_impl.py
+++ b/lightrag/kg/mongo_impl.py
@@ -2,7 +2,7 @@ import os
 from tqdm.asyncio import tqdm as tqdm_async
 from dataclasses import dataclass
 from pymongo import MongoClient
-
+from typing import Union
 from lightrag.utils import logger
 
 from lightrag.base import BaseKVStorage
@@ -41,11 +41,35 @@ class MongoKVStorage(BaseKVStorage):
         return set([s for s in data if s not in existing_ids])
 
     async def upsert(self, data: dict[str, dict]):
-        for k, v in tqdm_async(data.items(), desc="Upserting"):
-            self._data.update_one({"_id": k}, {"$set": v}, upsert=True)
-            data[k]["_id"] = k
+        if self.namespace == "llm_response_cache":
+            for mode, items in data.items():
+                for k, v in tqdm_async(items.items(), desc="Upserting"):
+                    key = f"{mode}_{k}"
+                    result = self._data.update_one(
+                        {"_id": key}, {"$setOnInsert": v}, upsert=True
+                    )
+                    if result.upserted_id:
+                        logger.debug(f"\nInserted new document with key: {key}")
+                    data[mode][k]["_id"] = key
+        else:
+            for k, v in tqdm_async(data.items(), desc="Upserting"):
+                self._data.update_one({"_id": k}, {"$set": v}, upsert=True)
+                data[k]["_id"] = k
         return data
 
+    async def get_by_mode_and_id(self, mode: str, id: str) -> Union[dict, None]:
+        if "llm_response_cache" == self.namespace:
+            res = {}
+            v = self._data.find_one({"_id": mode + "_" + id})
+            if v:
+                res[id] = v
+                logger.debug(f"llm_response_cache find one by:{id}")
+                return res
+            else:
+                return None
+        else:
+            return None
+
     async def drop(self):
         """ """
         pass
diff --git a/lightrag/kg/neo4j_impl.py b/lightrag/kg/neo4j_impl.py
index 884fcb40..8c2afb5d 100644
--- a/lightrag/kg/neo4j_impl.py
+++ b/lightrag/kg/neo4j_impl.py
@@ -39,6 +39,7 @@ class Neo4JStorage(BaseGraphStorage):
         URI = os.environ["NEO4J_URI"]
         USERNAME = os.environ["NEO4J_USERNAME"]
         PASSWORD = os.environ["NEO4J_PASSWORD"]
+        MAX_CONNECTION_POOL_SIZE = os.environ.get("NEO4J_MAX_CONNECTION_POOL_SIZE", 800)
         DATABASE = os.environ.get(
             "NEO4J_DATABASE"
         )  # If this param is None, the home database will be used. If it is not None, the specified database will be used.
@@ -47,7 +48,11 @@ class Neo4JStorage(BaseGraphStorage):
             URI, auth=(USERNAME, PASSWORD)
         )
         _database_name = "home database" if DATABASE is None else f"database {DATABASE}"
-        with GraphDatabase.driver(URI, auth=(USERNAME, PASSWORD)) as _sync_driver:
+        with GraphDatabase.driver(
+            URI,
+            auth=(USERNAME, PASSWORD),
+            max_connection_pool_size=MAX_CONNECTION_POOL_SIZE,
+        ) as _sync_driver:
             try:
                 with _sync_driver.session(database=DATABASE) as session:
                     try: