diff --git a/README.md b/README.md
index 9843ea0..07379f3 100644
--- a/README.md
+++ b/README.md
@@ -74,11 +74,15 @@ cp config-template.json config.json
 
 在使用时只需要更改 model 和 channel 配置块下的 type 字段，即可在任意模型和应用间完成切换，连接不同的通路。下面将依次介绍各个 模型 及 应用 的配置和运行过程。
 
-#### settings
+#### model 配置
+
++ type: chatgpt
+  + `max_history_num`[optional]: 对话最大记忆长度，超过该长度则清理前面的记忆。
+
+#### common 配置
 
 + `clear_memory_commands`: 对话内指令，主动清空前文记忆，字符串数组可自定义指令别名。
   + default: ["#清除记忆"]
-+ `max_history_per_session`[optional]: 对话最大记忆长度，超过该长度则清理前面的记忆。
 
 ## 二、选择模型
 
diff --git a/config-template.json b/config-template.json
index 3cf788b..062079b 100644
--- a/config-template.json
+++ b/config-template.json
@@ -57,7 +57,7 @@
       "port": "80"
     }
   },
-  "settings": {
+  "common": {
     "clear_memory_commands": ["#清除记忆"]
   }
 }
diff --git a/config.py b/config.py
index 3598f98..3c9ab17 100644
--- a/config.py
+++ b/config.py
@@ -54,10 +54,10 @@ def channel_conf_val(channel_type, key, default=None):
     return val
 
 
-def settings_conf():
-    return config.get('settings')
+def common_conf():
+    return config.get('common')
 
 
-def settings_conf_val(key, default=None):
-    return config.get('settings').get(key, default)
+def common_conf_val(key, default=None):
+    return config.get('common').get(key, default)
 
diff --git a/model/openai/chatgpt_model.py b/model/openai/chatgpt_model.py
index 7cf6cfc..2679ee3 100644
--- a/model/openai/chatgpt_model.py
+++ b/model/openai/chatgpt_model.py
@@ -1,7 +1,7 @@
 # encoding:utf-8
 
 from model.model import Model
-from config import model_conf, settings_conf_val
+from config import model_conf, common_conf_val
 from common import const
 from common import log
 import openai
@@ -22,7 +22,7 @@ class ChatGPTModel(Model):
         if not context or not context.get('type') or context.get('type') == 'TEXT':
             log.info("[CHATGPT] query={}".format(query))
             from_user_id = context['from_user_id']
-            clear_memory_commands = settings_conf_val('clear_memory_commands', ['#清除记忆'])
+            clear_memory_commands = common_conf_val('clear_memory_commands', ['#清除记忆'])
             if query in clear_memory_commands:
                 Session.clear_session(from_user_id)
                 return '记忆已清除'
@@ -196,7 +196,7 @@ class Session(object):
     @staticmethod
     def save_session(query, answer, user_id, used_tokens=0):
         max_tokens = model_conf(const.OPEN_AI).get('conversation_max_tokens')
-        max_history_per_session = model_conf(const.OPEN_AI).get('max_history_per_session', None)
+        max_history_num = model_conf(const.OPEN_AI).get('max_history_num', None)
         if not max_tokens or max_tokens > 4000:
             # default value
             max_tokens = 1000
@@ -211,8 +211,9 @@ class Session(object):
             session.pop(1)
             session.pop(1)
 
-        if max_history_per_session is not None:
-            while len(session) > max_history_per_session + 1:
+        if max_history_num is not None:
+            while len(session) > max_history_num * 2 + 1:
+                session.pop(1)
                 session.pop(1)
 
     @staticmethod
diff --git a/model/openai/open_ai_model.py b/model/openai/open_ai_model.py
index 8895482..78615bf 100644
--- a/model/openai/open_ai_model.py
+++ b/model/openai/open_ai_model.py
@@ -1,7 +1,7 @@
 # encoding:utf-8
 
 from model.model import Model
-from config import model_conf, settings_conf_val
+from config import model_conf, common_conf_val
 from common import const
 from common import log
 import openai
@@ -20,7 +20,7 @@ class OpenAIModel(Model):
         if not context or not context.get('type') or context.get('type') == 'TEXT':
             log.info("[OPEN_AI] query={}".format(query))
             from_user_id = context['from_user_id']
-            clear_memory_commands = settings_conf_val('clear_memory_commands', ['#清除记忆'])
+            clear_memory_commands = common_conf_val('clear_memory_commands', ['#清除记忆'])
             if query in clear_memory_commands:
                 Session.clear_session(from_user_id)
                 return '记忆已清除'