diff --git a/.env.example b/.env.example
index 7a991af..6b2b323 100644
--- a/.env.example
+++ b/.env.example
@@ -1,6 +1,7 @@
 [MONITOR]
 OFFLINE_THRESHOLD = 600
 DATA_TIMEOUT = 259200
+RETENTION_TIME = 86400
 
 [REDIS]
 HOST = ''
diff --git a/application/common/lib/SystemMonitor.php b/application/common/lib/SystemMonitor.php
index b6e0e5b..1bbc6d9 100644
--- a/application/common/lib/SystemMonitor.php
+++ b/application/common/lib/SystemMonitor.php
@@ -167,7 +167,7 @@ static public function setCollection($uuid, $data)
             Cache::store('redis')->handler()
                 ->zAdd("system_monitor:collection:$uuid", time(), $data);
             Cache::store('redis')->handler()
-                ->zRemRangeByScore("system_monitor:collection:$uuid", 0, time() - Env::get("MONITOR.DATA_TIMEOUT"));
+                ->zRemRangeByScore("system_monitor:collection:$uuid", 0, time() - Env::get("MONITOR.RETENTION_TIME"));
             Cache::store('redis')->handler()->expire("system_monitor:collection:$uuid", Env::get("MONITOR.DATA_TIMEOUT"));
             return ['code' => 200, 'message' => "OK"];
         } catch (Exception $e) {