Core/Maps: Implement optional pre-loading of maps.

- Option to preload basemaps upon server load (BaseMapLoadAllGrids)
- Option to preload instance maps upon map load (InstanceMapLoadAllGrids)
- Change default logging to only log mmap errors to server log
- Add new public to map to load all cells in map
- change debug loadcells to use new function instead

(cherry picked from commit 971f4ccab87ba95e584d5761f686cc2a86f5af9d)

7 files changed, 61 insertions, 6 deletions

diff --git a/src/server/game/Maps/Map.cpp b/src/server/game/Maps/Map.cpp
index da12d8e871a..51554d67c4c 100644
--- a/src/server/game/Maps/Map.cpp
+++ b/src/server/game/Maps/Map.cpp
@@ -132,9 +132,9 @@ void Map::LoadMMap(int gx, int gy)
     bool mmapLoadResult = MMAP::MMapFactory::createOrGetMMapManager()->loadMap((sWorld->GetDataPath() + "mmaps").c_str(), GetId(), gx, gy);
 
     if (mmapLoadResult)
-        TC_LOG_DEBUG("maps", "MMAP loaded name:%s, id:%d, x:%d, y:%d (mmap rep.: x:%d, y:%d)", GetMapName(), GetId(), gx, gy, gx, gy);
+        TC_LOG_DEBUG("mmaps", "MMAP loaded name:%s, id:%d, x:%d, y:%d (mmap rep.: x:%d, y:%d)", GetMapName(), GetId(), gx, gy, gx, gy);
     else
-        TC_LOG_ERROR("maps", "Could not load MMAP name:%s, id:%d, x:%d, y:%d (mmap rep.: x:%d, y:%d)", GetMapName(), GetId(), gx, gy, gx, gy);
+        TC_LOG_ERROR("mmaps", "Could not load MMAP name:%s, id:%d, x:%d, y:%d (mmap rep.: x:%d, y:%d)", GetMapName(), GetId(), gx, gy, gx, gy);
 }
 
 void Map::LoadVMap(int gx, int gy)
@@ -208,6 +208,13 @@ void Map::LoadMapAndVMap(int gx, int gy)
     }
 }
 
+void Map::LoadAllCells()
+{
+    for (uint32 cellX = 0; cellX < TOTAL_NUMBER_OF_CELLS_PER_MAP; cellX++)
+        for (uint32 cellY = 0; cellY < TOTAL_NUMBER_OF_CELLS_PER_MAP; cellY++)
+            LoadGrid((cellX + 0.5f - CENTER_GRID_CELL_ID) * SIZE_OF_GRID_CELL, (cellY + 0.5f - CENTER_GRID_CELL_ID) * SIZE_OF_GRID_CELL);
+}
+
 void Map::InitStateMachine()
 {
     si_GridStates[GRID_STATE_INVALID] = new InvalidState;
diff --git a/src/server/game/Maps/Map.h b/src/server/game/Maps/Map.h
index 6a917555fb0..6a87a1e3246 100644
--- a/src/server/game/Maps/Map.h
+++ b/src/server/game/Maps/Map.h
@@ -313,6 +313,7 @@ class TC_GAME_API Map : public GridRefManager<NGridType>
         bool GetUnloadLock(const GridCoord &p) const { return getNGrid(p.x_coord, p.y_coord)->getUnloadLock(); }
         void SetUnloadLock(const GridCoord &p, bool on) { getNGrid(p.x_coord, p.y_coord)->setUnloadExplicitLock(on); }
         void LoadGrid(float x, float y);
+        void LoadAllCells();
         bool UnloadGrid(NGridType& ngrid, bool pForce);
         virtual void UnloadAll();
 
diff --git a/src/server/game/Maps/MapInstanced.cpp b/src/server/game/Maps/MapInstanced.cpp
index e277746290a..12cec6d8633 100644
--- a/src/server/game/Maps/MapInstanced.cpp
+++ b/src/server/game/Maps/MapInstanced.cpp
@@ -238,6 +238,9 @@ InstanceMap* MapInstanced::CreateInstance(uint32 InstanceId, InstanceSave* save,
     bool load_data = save != NULL;
     map->CreateInstanceData(load_data);
 
+    if (sWorld->getBoolConfig(CONFIG_INSTANCEMAP_LOAD_GRIDS))
+        map->LoadAllCells();
+
     m_InstancedMaps[InstanceId] = map;
     return map;
 }
diff --git a/src/server/game/World/World.cpp b/src/server/game/World/World.cpp
index 2babb9121e8..c77bcfb5962 100644
--- a/src/server/game/World/World.cpp
+++ b/src/server/game/World/World.cpp
@@ -653,6 +653,18 @@ void World::LoadConfigSettings(bool reload)
     m_bool_configs[CONFIG_PRESERVE_CUSTOM_CHANNELS] = sConfigMgr->GetBoolDefault("PreserveCustomChannels", false);
     m_int_configs[CONFIG_PRESERVE_CUSTOM_CHANNEL_DURATION] = sConfigMgr->GetIntDefault("PreserveCustomChannelDuration", 14);
     m_bool_configs[CONFIG_GRID_UNLOAD] = sConfigMgr->GetBoolDefault("GridUnload", true);
+    m_bool_configs[CONFIG_BASEMAP_LOAD_GRIDS] = sConfigMgr->GetBoolDefault("BaseMapLoadAllGrids", false);
+    if (m_bool_configs[CONFIG_BASEMAP_LOAD_GRIDS] && m_bool_configs[CONFIG_GRID_UNLOAD])
+    {
+        TC_LOG_ERROR("server.loading", "BaseMapLoadAllGrids enabled, but GridUnload also enabled. GridUnload must be disabled to enable base map pre-loading. Base map pre-loading disabled");
+        m_bool_configs[CONFIG_BASEMAP_LOAD_GRIDS] = false;
+    }
+    m_bool_configs[CONFIG_INSTANCEMAP_LOAD_GRIDS] = sConfigMgr->GetBoolDefault("InstanceMapLoadAllGrids", false);
+    if (m_bool_configs[CONFIG_INSTANCEMAP_LOAD_GRIDS] && m_bool_configs[CONFIG_GRID_UNLOAD])
+    {
+        TC_LOG_ERROR("server.loading", "InstanceMapLoadAllGrids enabled, but GridUnload also enabled. GridUnload must be disabled to enable instance map pre-loading. Instance map pre-loading disabled");
+        m_bool_configs[CONFIG_INSTANCEMAP_LOAD_GRIDS] = false;
+    }
     m_int_configs[CONFIG_INTERVAL_SAVE] = sConfigMgr->GetIntDefault("PlayerSaveInterval", 15 * MINUTE * IN_MILLISECONDS);
     m_int_configs[CONFIG_INTERVAL_DISCONNECT_TOLERANCE] = sConfigMgr->GetIntDefault("DisconnectToleranceInterval", 0);
     m_bool_configs[CONFIG_STATS_SAVE_ONLY_ON_LOGOUT] = sConfigMgr->GetBoolDefault("PlayerSave.Stats.SaveOnlyOnLogout", true);
@@ -2060,6 +2072,19 @@ void World::SetInitialWorldSettings()
     TC_LOG_INFO("server.loading", "Loading battle pets info...");
     BattlePetMgr::Initialize();
 
+    // Preload all cells, if required for the base maps
+    if (sWorld->getBoolConfig(CONFIG_BASEMAP_LOAD_GRIDS))
+    {
+        sMapMgr->DoForAllMaps([](Map* map)
+        {
+            if (!map->Instanceable())
+            {
+                TC_LOG_INFO("server.loading", "Pre-loading base map data for map %u", map->GetId());
+                map->LoadAllCells();
+            }
+        });
+    }
+
     uint32 startupDuration = GetMSTimeDiffToNow(startupBegin);
 
     TC_LOG_INFO("server.worldserver", "World initialized in %u minutes %u seconds", (startupDuration / 60000), ((startupDuration % 60000) / 1000));
diff --git a/src/server/game/World/World.h b/src/server/game/World/World.h
index cffab97ed7c..84b1ba556e3 100644
--- a/src/server/game/World/World.h
+++ b/src/server/game/World/World.h
@@ -177,6 +177,8 @@ enum WorldBoolConfigs
     CONFIG_FEATURE_SYSTEM_CHARACTER_UNDELETE_ENABLED,
     CONFIG_RESET_DUEL_COOLDOWNS,
     CONFIG_RESET_DUEL_HEALTH_MANA,
+    CONFIG_BASEMAP_LOAD_GRIDS,
+    CONFIG_INSTANCEMAP_LOAD_GRIDS,
     BOOL_CONFIG_VALUE_COUNT
 };
 
diff --git a/src/server/scripts/Commands/cs_debug.cpp b/src/server/scripts/Commands/cs_debug.cpp
index 05686aa9828..b2094df08ef 100644
--- a/src/server/scripts/Commands/cs_debug.cpp
+++ b/src/server/scripts/Commands/cs_debug.cpp
@@ -1414,10 +1414,7 @@ public:
         if (!map)
             map = player->GetMap();
 
-        for (uint32 cellX = 0; cellX < TOTAL_NUMBER_OF_CELLS_PER_MAP; cellX++)
-            for (uint32 cellY = 0; cellY < TOTAL_NUMBER_OF_CELLS_PER_MAP; cellY++)
-                map->LoadGrid((cellX + 0.5f - CENTER_GRID_CELL_ID) * SIZE_OF_GRID_CELL, (cellY + 0.5f - CENTER_GRID_CELL_ID) * SIZE_OF_GRID_CELL);
-
+        map->LoadAllCells();
         handler->PSendSysMessage("Cells loaded (mapId: %u)", map->GetId());
         return true;
     }
diff --git a/src/server/worldserver/worldserver.conf.dist b/src/server/worldserver/worldserver.conf.dist
index 49f05e87222..7f9f59a5209 100644
--- a/src/server/worldserver/worldserver.conf.dist
+++ b/src/server/worldserver/worldserver.conf.dist
@@ -293,6 +293,25 @@ MaxOverspeedPings = 2
 GridUnload = 1
 
 #
+#    BaseMapLoadAllGrids
+#        Description: Load all grids for base maps upon load. Requires GridUnload to be 0.
+#                     This will take around 5GB of ram upon server load, and will take some time
+#                     to initially load the server.
+#        Default:     0 - (Don't pre-load all base maps, dynamically load as used)
+#                     1 - (Preload all grids in all base maps upon load)
+
+BaseMapLoadAllGrids = 0
+
+#
+#    InstanceMapLoadAllGrids
+#        Description: Load all grids for instance maps upon load. Requires GridUnload to be 0.
+#                     Upon loading an instance map, all creatures/objects in the map will be pre-loaded
+#        Default:     0 - (Don't pre-load all base maps, dynamically load as used)
+#                     1 - (Preload all grids in the instance upon load)
+
+InstanceMapLoadAllGrids = 0
+
+#
 #    SocketTimeOutTime
 #        Description: Time (in milliseconds) after which a connection being idle on the character
 #                     selection screen is disconnected.
@@ -3498,6 +3517,7 @@ Logger.server=3,Console Server
 Logger.commands.gm=3,Console GM
 Logger.sql.sql=5,Console DBErrors
 Logger.sql.updates=3,Console Server
+Logger.mmaps=3,Server
 
 #Logger.achievement=3,Console Server
 #Logger.addon=3,Console Server