From a974f957434b63c905900669b778762c1b80a3d2 Mon Sep 17 00:00:00 2001
From: muharem <ismailov.m.h@gmail.com>
Date: Tue, 24 Jan 2023 16:05:22 +0100
Subject: [PATCH] Scheduler pre block limit note

---
 bin/node/runtime/src/lib.rs |  3 +++
 frame/referenda/src/lib.rs  | 15 +++++++--------
 frame/scheduler/src/lib.rs  |  4 ++++
 3 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/bin/node/runtime/src/lib.rs b/bin/node/runtime/src/lib.rs
index 0ac6ade9127e8..71b5ec40866e3 100644
--- a/bin/node/runtime/src/lib.rs
+++ b/bin/node/runtime/src/lib.rs
@@ -356,7 +356,10 @@ impl pallet_scheduler::Config for Runtime {
 	type RuntimeCall = RuntimeCall;
 	type MaximumWeight = MaximumSchedulerWeight;
 	type ScheduleOrigin = EnsureRoot<AccountId>;
+	#[cfg(feature = "runtime-benchmarks")]
 	type MaxScheduledPerBlock = ConstU32<512>;
+	#[cfg(not(feature = "runtime-benchmarks"))]
+	type MaxScheduledPerBlock = ConstU32<50>;
 	type WeightInfo = pallet_scheduler::weights::SubstrateWeight<Runtime>;
 	type OriginPrivilegeCmp = EqualPrivilegeOnly;
 	type Preimages = Preimage;
diff --git a/frame/referenda/src/lib.rs b/frame/referenda/src/lib.rs
index 0b846faf88558..17f600cd861fc 100644
--- a/frame/referenda/src/lib.rs
+++ b/frame/referenda/src/lib.rs
@@ -814,22 +814,21 @@ impl<T: Config<I>, I: 'static> Pallet<T, I> {
 		let when = (when.saturating_add(alarm_interval.saturating_sub(One::one())) /
 			alarm_interval)
 			.saturating_mul(alarm_interval);
-		let maybe_result = T::Scheduler::schedule(
+		let result = T::Scheduler::schedule(
 			DispatchTime::At(when),
 			None,
 			128u8,
 			frame_system::RawOrigin::Root.into(),
 			call,
-		)
-		.ok()
-		.map(|x| (when, x));
+		);
 		debug_assert!(
-			maybe_result.is_some(),
-			"Unable to schedule a new alarm at #{:?} (now: #{:?})?!",
+			result.is_ok(),
+			"Unable to schedule a new alarm at #{:?} (now: #{:?}), scheduler error: `{:?}`",
 			when,
-			frame_system::Pallet::<T>::block_number()
+			frame_system::Pallet::<T>::block_number(),
+			result.unwrap_err(),
 		);
-		maybe_result
+		result.ok().map(|x| (when, x))
 	}
 
 	/// Mutate a referendum's `status` into the correct deciding state.
diff --git a/frame/scheduler/src/lib.rs b/frame/scheduler/src/lib.rs
index afc4fd66e76cb..7bc4ddf1b511d 100644
--- a/frame/scheduler/src/lib.rs
+++ b/frame/scheduler/src/lib.rs
@@ -217,6 +217,10 @@ pub mod pallet {
 		type OriginPrivilegeCmp: PrivilegeCmp<Self::PalletsOrigin>;
 
 		/// The maximum number of scheduled calls in the queue for a single block.
+		///
+		/// NOTE:
+		/// + Dependent pallets' benchmarks might require a higher limit for the setting. Set a
+		/// higher limit under `runtime-benchmarks` feature.
 		#[pallet::constant]
 		type MaxScheduledPerBlock: Get<u32>;