diff --git a/map/traffic_manager.cpp b/map/traffic_manager.cpp
index d12b5f7b5e..4030587493 100644
--- a/map/traffic_manager.cpp
+++ b/map/traffic_manager.cpp
@@ -378,7 +378,7 @@ void TrafficManager::OnTrafficDataResponse(traffic::TrafficInfo && info)
       size_t const dataSize = info.GetColoring().size() * kElementSize;
       m_currentCacheSizeBytes += (dataSize - it->second.m_dataSize);
       it->second.m_dataSize = dataSize;
-      CheckCacheSize();
+      ShrinkCacheToAllowableSize();
     }
 
     UpdateState();
@@ -399,7 +399,7 @@ void TrafficManager::UniteActiveMwms(set<MwmSet::MwmId> & activeMwms) const
   activeMwms.insert(m_activeRoutingMwms.cbegin(), m_activeRoutingMwms.cend());
 }
 
-void TrafficManager::CheckCacheSize()
+void TrafficManager::ShrinkCacheToAllowableSize()
 {
   // Calculating number of different active mwms.
   set<MwmSet::MwmId> activeMwms;
diff --git a/map/traffic_manager.hpp b/map/traffic_manager.hpp
index ffef9de631..dbb984b2d5 100644
--- a/map/traffic_manager.hpp
+++ b/map/traffic_manager.hpp
@@ -15,6 +15,7 @@
 
 #include "base/thread.hpp"
 
+#include "std/algorithm.hpp"
 #include "std/atomic.hpp"
 #include "std/chrono.hpp"
 #include "std/map.hpp"
@@ -105,6 +106,11 @@ private:
   void OnTrafficDataResponse(traffic::TrafficInfo && info);
   void OnTrafficRequestFailed(traffic::TrafficInfo && info);
 
+  /// \brief Updates |activeMwms| and request traffic data.
+  /// \param rect is a rectangle covering a new active mwm set.
+  /// \note |lastMwmsByRect|/|activeMwms| may be either |m_lastDrapeMwmsByRect/|m_activeDrapeMwms|
+  /// or |m_lastRoutingMwmsByRect|/|m_activeRoutingMwms|.
+  /// \note |m_mutex| is locked inside the method. So the method should be called without |m_mutex|.
   void UpdateActiveMwms(m2::RectD const & rect, vector<MwmSet::MwmId> & lastMwmsByRect,
                         set<MwmSet::MwmId> & activeMwms);
 
@@ -114,7 +120,7 @@ private:
 
   void Clear();
   void ClearCache(MwmSet::MwmId const & mwmId);
-  void CheckCacheSize();
+  void ShrinkCacheToAllowableSize();
 
   void UpdateState();
   void ChangeState(TrafficState newState);
@@ -129,8 +135,7 @@ private:
   {
     set<MwmSet::MwmId> activeMwms;
     UniteActiveMwms(activeMwms);
-    for (auto const & mwmId : activeMwms)
-      f(mwmId);
+    for_each(activeMwms.begin(), activeMwms.end(), forward<F>(f));
   }
 
   GetMwmsByRectFn m_getMwmsByRectFn;