From ab55aa4e5a3223ada9a0593dd4cbcb7a37fc5bc4 Mon Sep 17 00:00:00 2001
From: Stoabrogga <38475780+Stoabrogga@users.noreply.github.com>
Date: Mon, 30 Sep 2019 17:06:32 +0200
Subject: [PATCH] feat(Core/Config): Add parameter to load all grids of all
 non-instanced maps on server start (#2283)

---
 src/server/game/Maps/Map.cpp                 |  7 +++++
 src/server/game/Maps/Map.h                   |  1 +
 src/server/game/World/World.cpp              | 24 +++++++++++++++++
 src/server/game/World/World.h                |  1 +
 src/server/worldserver/worldserver.conf.dist | 28 +++++++++-----------
 5 files changed, 45 insertions(+), 16 deletions(-)

diff --git a/src/server/game/Maps/Map.cpp b/src/server/game/Maps/Map.cpp
index ba37dfd3f..2045693d0 100644
--- a/src/server/game/Maps/Map.cpp
+++ b/src/server/game/Maps/Map.cpp
@@ -469,6 +469,13 @@ void Map::LoadGrid(float x, float y)
     EnsureGridLoaded(Cell(x, y));
 }
 
+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);
+}
+
 bool Map::AddPlayerToMap(Player* player)
 { 
     CellCoord cellCoord = Trinity::ComputeCellCoord(player->GetPositionX(), player->GetPositionY());
diff --git a/src/server/game/Maps/Map.h b/src/server/game/Maps/Map.h
index a090b7bfa..d626ede2b 100644
--- a/src/server/game/Maps/Map.h
+++ b/src/server/game/Maps/Map.h
@@ -319,6 +319,7 @@ class Map : public GridRefManager<NGridType>
         }
 
         void LoadGrid(float x, float y);
+        void LoadAllCells();
         bool UnloadGrid(NGridType& ngrid);
         virtual void UnloadAll();
 
diff --git a/src/server/game/World/World.cpp b/src/server/game/World/World.cpp
index d568ea1c5..fe02de711 100644
--- a/src/server/game/World/World.cpp
+++ b/src/server/game/World/World.cpp
@@ -1326,6 +1326,9 @@ void World::LoadConfigSettings(bool reload)
     // Prevent players AFK from being logged out
     m_int_configs[CONFIG_AFK_PREVENT_LOGOUT] = sConfigMgr->GetIntDefault("PreventAFKLogout", 0);
 
+    // Preload all grids of all non-instanced maps
+    m_bool_configs[CONFIG_PRELOAD_ALL_NON_INSTANCED_MAP_GRIDS] = sConfigMgr->GetIntDefault("PreloadAllNonInstancedMapGrids", false);
+
     // call ScriptMgr if we're reloading the configuration
     sScriptMgr->OnAfterConfigLoad(reload);
 }
@@ -1958,6 +1961,27 @@ void World::SetInitialWorldSettings()
     sEluna->RunScripts();
     sEluna->OnConfigLoad(false,false); // Must be done after Eluna is initialized and scripts have run.
 #endif
+
+    if (sWorld->getBoolConfig(CONFIG_PRELOAD_ALL_NON_INSTANCED_MAP_GRIDS))
+    {
+        sLog->outString("Loading all grids for all non-instanced maps...");
+
+        for (uint32 i = 0; i < sMapStore.GetNumRows(); ++i)
+        {
+            MapEntry const* mapEntry = sMapStore.LookupEntry(i);
+
+            if (mapEntry && !mapEntry->Instanceable())
+            {
+                Map* map = sMapMgr->CreateBaseMap(mapEntry->MapID);
+
+                if (map)
+                {
+                    sLog->outString(">> Loading all grids for map %u", map->GetId());
+                    map->LoadAllCells();
+                }
+            }
+        }
+    }
     
     uint32 startupDuration = GetMSTimeDiffToNow(startupBegin);
     sLog->outString();
diff --git a/src/server/game/World/World.h b/src/server/game/World/World.h
index ae779a039..6776ded13 100644
--- a/src/server/game/World/World.h
+++ b/src/server/game/World/World.h
@@ -169,6 +169,7 @@ enum WorldBoolConfigs
     CONFIG_CHECK_GOBJECT_LOS,
     CONFIG_CLOSE_IDLE_CONNECTIONS,
     CONFIG_LFG_LOCATION_ALL, // Player can join LFG anywhere
+    CONFIG_PRELOAD_ALL_NON_INSTANCED_MAP_GRIDS,
     BOOL_CONFIG_VALUE_COUNT
 };
 
diff --git a/src/server/worldserver/worldserver.conf.dist b/src/server/worldserver/worldserver.conf.dist
index 900d5c7d4..7f0d0cce4 100644
--- a/src/server/worldserver/worldserver.conf.dist
+++ b/src/server/worldserver/worldserver.conf.dist
@@ -203,15 +203,6 @@ SaveRespawnTimeImmediately = 1
 
 MaxOverspeedPings = 2
 
-#
-#    GridUnload
-#        Description: Unload grids to save memory. Can be disabled if enough memory is available
-#                     to speed up moving players to new grids.
-#        Default:     1 - (enable, Unload grids)
-#                     0 - (disable, Do not unload grids)
-
-GridUnload = 1
-
 #
 #    CloseIdleConnections
 #        Description: Automatically close idle connections.
@@ -246,13 +237,6 @@ SocketTimeOutTimeActive = 60000
 
 SessionAddDelay = 10000
 
-#
-#    GridCleanUpDelay
-#        Description: Time (in milliseconds) grid clean up delay.
-#        Default:     300000 - (5 minutes)
-
-GridCleanUpDelay = 300000
-
 #
 #    MapUpdateInterval
 #        Description: Time (milliseconds) for map update interval.
@@ -416,6 +400,18 @@ CleanCharacterDB = 0
 
 PersistentCharacterCleanFlags = 0
 
+#
+#    PreloadAllNonInstancedMapGrids
+#        Description: Preload all grids on all non-instanced maps. This will take a great amount
+#                     of additional RAM (ca. 9 GB) and causes the server to take longer to start,
+#                     but can increase performance if used on a server with a high amount of players.
+#                     It will also activate all creatures which are set active (e.g. the Fel Reavers
+#                     in Hellfire Peninsula) on server start.
+#        Default:     0 - (Disabled)
+#                     1 - (Enabled)
+
+PreloadAllNonInstancedMapGrids = 0
+
 #
 ###################################################################################################