diff --git a/src/record_manager.cpp b/src/record_manager.cpp
index ad9c37b..7217023 100644
--- a/src/record_manager.cpp
+++ b/src/record_manager.cpp
@@ -6,9 +6,30 @@
 #include <ctime>
 #include <fstream>
 #include <iostream>
+#include <optional>
 
 #include "logger.hpp"
 
+namespace
+{
+std::optional<int64_t> getEarliestRecordMsInternal(
+    const std::unordered_map<std::string, std::vector<RecordFileInfo>>& index_)
+{
+    int64_t earliest = -1;
+
+    for (auto& kv : index_)
+    {
+        for (auto& f : kv.second)
+        {
+            if (earliest < 0 || f.start_ms < earliest) earliest = f.start_ms;
+        }
+    }
+
+    if (earliest < 0) return std::nullopt;
+    return earliest;
+}
+}  // namespace
+
 std::shared_ptr<RecordManager> g_record_manager = nullptr;
 
 extern std::atomic<bool> g_running;
@@ -125,24 +146,6 @@ bool RecordManager::loadSrsConfig()
     return true;
 }
 
-std::optional<int64_t> RecordManager::getEarliestRecordMs()
-{
-    std::lock_guard<std::mutex> lock(index_mutex_);
-
-    int64_t earliest = -1;
-
-    for (auto& kv : index_)
-    {
-        for (auto& f : kv.second)
-        {
-            if (earliest < 0 || f.start_ms < earliest) earliest = f.start_ms;
-        }
-    }
-
-    if (earliest < 0) return std::nullopt;
-    return earliest;
-}
-
 void RecordManager::removeExpiredDays()
 {
     namespace fs = std::filesystem;
@@ -310,7 +313,11 @@ void RecordManager::startAutoScan(int interval_sec)
                 this->scanAll();
 
                 // ======= 新增：打印最早录像时间 + 磁盘使用率 =======
-                auto earliestOpt = this->getEarliestRecordMs();
+                std::optional<int64_t> earliestOpt;
+                {
+                    std::lock_guard<std::mutex> lock(index_mutex_);
+                    earliestOpt = getEarliestRecordMsInternal(index_);
+                }
                 if (earliestOpt.has_value())
                 {
                     std::string tReadable = RecordManager::toReadable(earliestOpt.value());