1 files changed, 35 insertions, 0 deletions
diff --git a/patches/server/0420-Fix-client-lag-on-advancement-loading.patch b/patches/server/0420-Fix-client-lag-on-advancement-loading.patch
new file mode 100644
index 0000000000..4866bbae4b
--- /dev/null
+++ b/patches/server/0420-Fix-client-lag-on-advancement-loading.patch
@@ -0,0 +1,35 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Jason Penilla <[email protected]>
+Date: Sat, 31 Oct 2020 11:49:01 -0700
+Subject: [PATCH] Fix client lag on advancement loading
+
+When new advancements are added via the UnsafeValues#loadAdvancement
+API, it triggers a full datapack reload when this is not necessary. The
+advancement is already loaded directly into the advancement registry,
+and the point of saving the advancement to the Bukkit datapack seems to
+be for persistence. By removing the call to reload datapacks when an
+advancement is loaded, the client no longer completely freezes up when
+adding a new advancement.
+To ensure the client still receives the updated advancement data, we
+manually reload the advancement data for all players, which
+normally takes place as a part of the datapack reloading.
+
+diff --git a/src/main/java/org/bukkit/craftbukkit/util/CraftMagicNumbers.java b/src/main/java/org/bukkit/craftbukkit/util/CraftMagicNumbers.java
+index 78bc460fff7d537109883f1469500f6f536c598e..5f0fd1d4fe419435ac7293106c0ebb5382d64074 100644
+--- a/src/main/java/org/bukkit/craftbukkit/util/CraftMagicNumbers.java
++++ b/src/main/java/org/bukkit/craftbukkit/util/CraftMagicNumbers.java
+@@ -318,7 +318,13 @@ public final class CraftMagicNumbers implements UnsafeValues {
+                     Bukkit.getLogger().log(Level.SEVERE, "Error saving advancement " + key, ex);
+                 }
+ 
+-                MinecraftServer.getServer().getPlayerList().reloadResources();
++                // Paper start - Fix client lag on advancement loading
++                //MinecraftServer.getServer().getPlayerList().reload();
++                MinecraftServer.getServer().getPlayerList().getPlayers().forEach(player -> {
++                    player.getAdvancements().reload(MinecraftServer.getServer().getAdvancements());
++                    player.getAdvancements().flushDirty(player);
++                });
++                // Paper end - Fix client lag on advancement loading
+ 
+                 return bukkit;
+             }