From 262b88f5b4a9b8d5afe8a13bb4058f7d2cc2b883 Mon Sep 17 00:00:00 2001
From: Chris Sosnin <chris125_@live.com>
Date: Wed, 1 Sep 2021 20:23:51 +0300
Subject: [PATCH] Add a note about ValidationData

---
 pallets/parachain-system/src/lib.rs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/pallets/parachain-system/src/lib.rs b/pallets/parachain-system/src/lib.rs
index 66519c6cc7c..dc603485674 100644
--- a/pallets/parachain-system/src/lib.rs
+++ b/pallets/parachain-system/src/lib.rs
@@ -453,6 +453,8 @@ pub mod pallet {
 	pub(super) type NewValidationCode<T: Config> = StorageValue<_, Vec<u8>, OptionQuery>;
 
 	/// The [`PersistedValidationData`] set for this block.
+	/// This value is expected to be set only once per block and it's never stored
+  	/// in the trie.
 	#[pallet::storage]
 	#[pallet::getter(fn validation_data)]
 	pub(super) type ValidationData<T: Config> = StorageValue<_, PersistedValidationData>;