From f8e5c63b2aefeb0ad003dcbb39926c27713cc0e1 Mon Sep 17 00:00:00 2001
From: gupnik <17176722+gupnik@users.noreply.github.com>
Date: Tue, 5 Nov 2024 14:24:37 +0530
Subject: [PATCH 01/16] Adds BlockNumberProvider

---
 substrate/frame/scheduler/src/lib.rs   |  7 +++--
 substrate/frame/scheduler/src/mock.rs  |  7 +++++
 substrate/frame/scheduler/src/tests.rs | 37 ++++++++++++++++++++++++++
 3 files changed, 49 insertions(+), 2 deletions(-)

diff --git a/substrate/frame/scheduler/src/lib.rs b/substrate/frame/scheduler/src/lib.rs
index 468099010bf9..82904c28af7e 100644
--- a/substrate/frame/scheduler/src/lib.rs
+++ b/substrate/frame/scheduler/src/lib.rs
@@ -107,7 +107,7 @@ use frame_system::{
 use scale_info::TypeInfo;
 use sp_io::hashing::blake2_256;
 use sp_runtime::{
-	traits::{BadOrigin, Dispatchable, One, Saturating, Zero},
+	traits::{BadOrigin, BlockNumberProvider, Dispatchable, One, Saturating, Zero},
 	BoundedVec, DispatchError, RuntimeDebug,
 };
 
@@ -292,6 +292,9 @@ pub mod pallet {
 
 		/// The preimage provider with which we look up call hashes to get the call.
 		type Preimages: QueryPreimage<H = Self::Hashing> + StorePreimage;
+
+		/// Provider for the block number. Normally this is the `frame_system` pallet.
+		type BlockNumberProvider: BlockNumberProvider<BlockNumber = BlockNumberFor<Self>>;
 	}
 
 	#[pallet::storage]
@@ -889,7 +892,7 @@ impl<T: Config> Pallet<T> {
 	fn resolve_time(
 		when: DispatchTime<BlockNumberFor<T>>,
 	) -> Result<BlockNumberFor<T>, DispatchError> {
-		let now = frame_system::Pallet::<T>::block_number();
+		let now = T::BlockNumberProvider::current_block_number();
 
 		let when = match when {
 			DispatchTime::At(x) => x,
diff --git a/substrate/frame/scheduler/src/mock.rs b/substrate/frame/scheduler/src/mock.rs
index 8d36ca1c42e3..8c95e796511d 100644
--- a/substrate/frame/scheduler/src/mock.rs
+++ b/substrate/frame/scheduler/src/mock.rs
@@ -227,6 +227,7 @@ impl Config for Test {
 	type WeightInfo = TestWeightInfo;
 	type OriginPrivilegeCmp = EqualPrivilegeOnly;
 	type Preimages = Preimage;
+	type BlockNumberProvider = frame_system::Pallet<Self>;
 }
 
 pub type LoggerCall = logger::Call<Test>;
@@ -244,6 +245,12 @@ pub fn run_to_block(n: u64) {
 	}
 }
 
+pub fn go_to_block(n: u64) {
+	System::set_block_number(n);
+	Scheduler::on_initialize(n);
+	Scheduler::on_finalize(n);
+}
+
 pub fn root() -> OriginCaller {
 	system::RawOrigin::Root.into()
 }
diff --git a/substrate/frame/scheduler/src/tests.rs b/substrate/frame/scheduler/src/tests.rs
index 3023a370a4b6..5eeef94d70b8 100644
--- a/substrate/frame/scheduler/src/tests.rs
+++ b/substrate/frame/scheduler/src/tests.rs
@@ -1636,6 +1636,7 @@ fn on_initialize_weight_is_correct() {
 		));
 
 		// Will include the named periodic only
+		System::set_block_number(1);
 		assert_eq!(
 			Scheduler::on_initialize(1),
 			TestWeightInfo::service_agendas_base() +
@@ -1648,6 +1649,7 @@ fn on_initialize_weight_is_correct() {
 		assert_eq!(logger::log(), vec![(root(), 2600u32)]);
 
 		// Will include anon and anon periodic
+		System::set_block_number(2);
 		assert_eq!(
 			Scheduler::on_initialize(2),
 			TestWeightInfo::service_agendas_base() +
@@ -1663,6 +1665,7 @@ fn on_initialize_weight_is_correct() {
 		assert_eq!(logger::log(), vec![(root(), 2600u32), (root(), 69u32), (root(), 42u32)]);
 
 		// Will include named only
+		System::set_block_number(3);
 		assert_eq!(
 			Scheduler::on_initialize(3),
 			TestWeightInfo::service_agendas_base() +
@@ -1678,6 +1681,7 @@ fn on_initialize_weight_is_correct() {
 		);
 
 		// Will contain none
+		System::set_block_number(4);
 		let actual_weight = Scheduler::on_initialize(4);
 		assert_eq!(
 			actual_weight,
@@ -3035,3 +3039,36 @@ fn unavailable_call_is_detected() {
 		assert!(!Preimage::is_requested(&hash));
 	});
 }
+
+#[test]
+fn basic_scheduling_with_skipped_blocks_works() {
+	new_test_ext().execute_with(|| {
+		// Call to schedule
+		let call =
+			RuntimeCall::Logger(LoggerCall::log { i: 42, weight: Weight::from_parts(10, 0) });
+
+		// BaseCallFilter should be implemented to accept `Logger::log` runtime call which is
+		// implemented for `BaseFilter` in the mock runtime
+		assert!(!<Test as frame_system::Config>::BaseCallFilter::contains(&call));
+
+		// Schedule call to be executed at the 4th block
+		assert_ok!(Scheduler::do_schedule(
+			DispatchTime::At(4),
+			None,
+			127,
+			root(),
+			Preimage::bound(call).unwrap()
+		));
+
+		// `log` runtime call should not have executed yet
+		go_to_block(3);
+		assert!(logger::log().is_empty());
+
+		go_to_block(6);
+		// `log` runtime call should have executed at block 4
+		assert_eq!(logger::log(), vec![(root(), 42u32)]);
+
+		go_to_block(100);
+		assert_eq!(logger::log(), vec![(root(), 42u32)]);
+	});
+}

From 455d7650965a1ddc5c797e27ecb539b034f81b10 Mon Sep 17 00:00:00 2001
From: gupnik <17176722+gupnik@users.noreply.github.com>
Date: Tue, 5 Nov 2024 14:25:47 +0530
Subject: [PATCH 02/16] Adds a Queue to handle non-sequential block numbers

---
 .../collectives-westend/src/lib.rs            |  4 ++
 polkadot/runtime/rococo/src/lib.rs            |  3 +
 polkadot/runtime/westend/src/lib.rs           |  3 +
 substrate/bin/node/runtime/src/lib.rs         |  5 ++
 substrate/frame/democracy/src/tests.rs        |  2 +
 substrate/frame/referenda/src/mock.rs         |  2 +
 substrate/frame/scheduler/src/lib.rs          | 63 +++++++++++++------
 substrate/frame/scheduler/src/mock.rs         |  1 +
 substrate/frame/scheduler/src/tests.rs        |  5 +-
 9 files changed, 66 insertions(+), 22 deletions(-)

diff --git a/cumulus/parachains/runtimes/collectives/collectives-westend/src/lib.rs b/cumulus/parachains/runtimes/collectives/collectives-westend/src/lib.rs
index 8cb2e42cb31b..4a20c68245ac 100644
--- a/cumulus/parachains/runtimes/collectives/collectives-westend/src/lib.rs
+++ b/cumulus/parachains/runtimes/collectives/collectives-westend/src/lib.rs
@@ -604,11 +604,13 @@ parameter_types! {
 #[cfg(not(feature = "runtime-benchmarks"))]
 parameter_types! {
 	pub const MaxScheduledPerBlock: u32 = 50;
+	pub const MaxScheduledBlocks: u32 = 50;
 }
 
 #[cfg(feature = "runtime-benchmarks")]
 parameter_types! {
 	pub const MaxScheduledPerBlock: u32 = 200;
+	pub const MaxScheduledBlocks: u32 = 200;
 }
 
 impl pallet_scheduler::Config for Runtime {
@@ -622,6 +624,8 @@ impl pallet_scheduler::Config for Runtime {
 	type WeightInfo = weights::pallet_scheduler::WeightInfo<Runtime>;
 	type OriginPrivilegeCmp = EqualOrGreatestRootCmp;
 	type Preimages = Preimage;
+	type BlockNumberProvider = frame_system::Pallet<Runtime>;
+	type MaxScheduledBlocks = MaxScheduledBlocks;
 }
 
 parameter_types! {
diff --git a/polkadot/runtime/rococo/src/lib.rs b/polkadot/runtime/rococo/src/lib.rs
index 5bcde612cf1b..8106822009bc 100644
--- a/polkadot/runtime/rococo/src/lib.rs
+++ b/polkadot/runtime/rococo/src/lib.rs
@@ -231,6 +231,7 @@ parameter_types! {
 	pub MaximumSchedulerWeight: Weight = Perbill::from_percent(80) *
 		BlockWeights::get().max_block;
 	pub const MaxScheduledPerBlock: u32 = 50;
+	pub const MaxScheduledBlocks: u32 = 50;
 	pub const NoPreimagePostponement: Option<u32> = Some(10);
 }
 
@@ -331,6 +332,8 @@ impl pallet_scheduler::Config for Runtime {
 	type WeightInfo = weights::pallet_scheduler::WeightInfo<Runtime>;
 	type OriginPrivilegeCmp = OriginPrivilegeCmp;
 	type Preimages = Preimage;
+	type BlockNumberProvider = frame_system::Pallet<Runtime>;
+	type MaxScheduledBlocks = MaxScheduledBlocks;
 }
 
 parameter_types! {
diff --git a/polkadot/runtime/westend/src/lib.rs b/polkadot/runtime/westend/src/lib.rs
index 970ef5318994..e35a27343d82 100644
--- a/polkadot/runtime/westend/src/lib.rs
+++ b/polkadot/runtime/westend/src/lib.rs
@@ -231,6 +231,7 @@ parameter_types! {
 	pub MaximumSchedulerWeight: frame_support::weights::Weight = Perbill::from_percent(80) *
 		BlockWeights::get().max_block;
 	pub const MaxScheduledPerBlock: u32 = 50;
+	pub const MaxScheduledBlocks: u32 = 50;
 	pub const NoPreimagePostponement: Option<u32> = Some(10);
 }
 
@@ -247,6 +248,8 @@ impl pallet_scheduler::Config for Runtime {
 	type WeightInfo = weights::pallet_scheduler::WeightInfo<Runtime>;
 	type OriginPrivilegeCmp = frame_support::traits::EqualPrivilegeOnly;
 	type Preimages = Preimage;
+	type BlockNumberProvider = frame_system::Pallet<Runtime>;
+	type MaxScheduledBlocks = MaxScheduledBlocks;
 }
 
 parameter_types! {
diff --git a/substrate/bin/node/runtime/src/lib.rs b/substrate/bin/node/runtime/src/lib.rs
index 12e8dc3e5077..3b271625e3c9 100644
--- a/substrate/bin/node/runtime/src/lib.rs
+++ b/substrate/bin/node/runtime/src/lib.rs
@@ -462,6 +462,11 @@ impl pallet_scheduler::Config for Runtime {
 	type WeightInfo = pallet_scheduler::weights::SubstrateWeight<Runtime>;
 	type OriginPrivilegeCmp = EqualPrivilegeOnly;
 	type Preimages = Preimage;
+	type BlockNumberProvider = frame_system::Pallet<Runtime>;
+	#[cfg(feature = "runtime-benchmarks")]
+	type MaxScheduledBlocks = ConstU32<512>;
+	#[cfg(not(feature = "runtime-benchmarks"))]
+	type MaxScheduledBlocks = ConstU32<50>;
 }
 
 impl pallet_glutton::Config for Runtime {
diff --git a/substrate/frame/democracy/src/tests.rs b/substrate/frame/democracy/src/tests.rs
index 10e5ee75611d..6a09a054452e 100644
--- a/substrate/frame/democracy/src/tests.rs
+++ b/substrate/frame/democracy/src/tests.rs
@@ -106,6 +106,8 @@ impl pallet_scheduler::Config for Test {
 	type WeightInfo = ();
 	type OriginPrivilegeCmp = EqualPrivilegeOnly;
 	type Preimages = ();
+	type BlockNumberProvider = frame_system::Pallet<Test>;
+	type MaxScheduledBlocks = ConstU32<100>;
 }
 
 #[derive_impl(pallet_balances::config_preludes::TestDefaultConfig)]
diff --git a/substrate/frame/referenda/src/mock.rs b/substrate/frame/referenda/src/mock.rs
index c96a50af8658..e45353408d76 100644
--- a/substrate/frame/referenda/src/mock.rs
+++ b/substrate/frame/referenda/src/mock.rs
@@ -81,6 +81,8 @@ impl pallet_scheduler::Config for Test {
 	type WeightInfo = ();
 	type OriginPrivilegeCmp = EqualPrivilegeOnly;
 	type Preimages = Preimage;
+	type BlockNumberProvider = frame_system::Pallet<Test>;
+	type MaxScheduledBlocks = ConstU32<100>;
 }
 #[derive_impl(pallet_balances::config_preludes::TestDefaultConfig)]
 impl pallet_balances::Config for Test {
diff --git a/substrate/frame/scheduler/src/lib.rs b/substrate/frame/scheduler/src/lib.rs
index 82904c28af7e..b9a7d2c46a42 100644
--- a/substrate/frame/scheduler/src/lib.rs
+++ b/substrate/frame/scheduler/src/lib.rs
@@ -295,6 +295,10 @@ pub mod pallet {
 
 		/// Provider for the block number. Normally this is the `frame_system` pallet.
 		type BlockNumberProvider: BlockNumberProvider<BlockNumber = BlockNumberFor<Self>>;
+
+		/// The maximum number of blocks that can be scheduled.
+		#[pallet::constant]
+		type MaxScheduledBlocks: Get<u32>;
 	}
 
 	#[pallet::storage]
@@ -328,6 +332,11 @@ pub mod pallet {
 	pub(crate) type Lookup<T: Config> =
 		StorageMap<_, Twox64Concat, TaskName, TaskAddress<BlockNumberFor<T>>>;
 
+	/// The queue of block numbers that have scheduled agendas.
+	#[pallet::storage]
+	pub(crate) type Queue<T: Config> =
+		StorageValue<_, BoundedVec<BlockNumberFor<T>, T::MaxScheduledBlocks>, ValueQuery>;
+
 	/// Events type.
 	#[pallet::event]
 	#[pallet::generate_deposit(pub(super) fn deposit_event)]
@@ -379,7 +388,8 @@ pub mod pallet {
 	#[pallet::hooks]
 	impl<T: Config> Hooks<BlockNumberFor<T>> for Pallet<T> {
 		/// Execute the scheduled calls
-		fn on_initialize(now: BlockNumberFor<T>) -> Weight {
+		fn on_initialize(_do_not_use_local_block_number: BlockNumberFor<T>) -> Weight {
+			let now = T::BlockNumberProvider::current_block_number();
 			let mut weight_counter = WeightMeter::with_limit(T::MaximumWeight::get());
 			Self::service_agendas(&mut weight_counter, now, u32::max_value());
 			weight_counter.consumed()
@@ -929,17 +939,23 @@ impl<T: Config> Pallet<T> {
 		let mut agenda = Agenda::<T>::get(when);
 		let index = if (agenda.len() as u32) < T::MaxScheduledPerBlock::get() {
 			// will always succeed due to the above check.
-			let _ = agenda.try_push(Some(what));
+			let _ = agenda.try_push(Some(what.clone()));
 			agenda.len() as u32 - 1
 		} else {
 			if let Some(hole_index) = agenda.iter().position(|i| i.is_none()) {
-				agenda[hole_index] = Some(what);
+				agenda[hole_index] = Some(what.clone());
 				hole_index as u32
 			} else {
 				return Err((DispatchError::Exhausted, what))
 			}
 		};
 		Agenda::<T>::insert(when, agenda);
+		Queue::<T>::mutate(|q| {
+			if let Err(index) = q.binary_search_by_key(&when, |x| *x) {
+				q.try_insert(index, when).map_err(|_| (DispatchError::Exhausted, what))?;
+			}
+			Ok(())
+		})?;
 		Ok(index)
 	}
 
@@ -955,6 +971,11 @@ impl<T: Config> Pallet<T> {
 			Some(_) => {},
 			None => {
 				Agenda::<T>::remove(when);
+				Queue::<T>::mutate(|q| {
+					if let Ok(index) = q.binary_search_by_key(&when, |x| *x) {
+						q.remove(index);
+					}
+				});
 			},
 		}
 	}
@@ -1160,24 +1181,30 @@ impl<T: Config> Pallet<T> {
 			return
 		}
 
-		let mut incomplete_since = now + One::one();
-		let mut when = IncompleteSince::<T>::take().unwrap_or(now);
-		let mut executed = 0;
+		let queue = Queue::<T>::get();
+		let end_index = match queue.binary_search_by_key(&now, |x| *x) {
+			Ok(end_index) => end_index.saturating_add(1),
+			Err(end_index) => {
+				if end_index == 0 {
+					return;
+				}
+				end_index
+			},
+		};
 
-		let max_items = T::MaxScheduledPerBlock::get();
-		let mut count_down = max;
-		let service_agenda_base_weight = T::WeightInfo::service_agenda_base(max_items);
-		while count_down > 0 && when <= now && weight.can_consume(service_agenda_base_weight) {
-			if !Self::service_agenda(weight, &mut executed, now, when, u32::max_value()) {
-				incomplete_since = incomplete_since.min(when);
+		let mut index = 0;
+		while index < end_index {
+			let when = queue[index];
+			let mut executed = 0;
+			if !Self::service_agenda(weight, &mut executed, now, when, max) {
+				break;
 			}
-			when.saturating_inc();
-			count_down.saturating_dec();
-		}
-		incomplete_since = incomplete_since.min(when);
-		if incomplete_since <= now {
-			IncompleteSince::<T>::put(incomplete_since);
+			index.saturating_inc();
 		}
+
+		Queue::<T>::mutate(|queue| {
+			queue.drain(0..index);
+		});
 	}
 
 	/// Returns `true` if the agenda was fully completed, `false` if it should be revisited at a
diff --git a/substrate/frame/scheduler/src/mock.rs b/substrate/frame/scheduler/src/mock.rs
index 8c95e796511d..73441d44f308 100644
--- a/substrate/frame/scheduler/src/mock.rs
+++ b/substrate/frame/scheduler/src/mock.rs
@@ -228,6 +228,7 @@ impl Config for Test {
 	type OriginPrivilegeCmp = EqualPrivilegeOnly;
 	type Preimages = Preimage;
 	type BlockNumberProvider = frame_system::Pallet<Self>;
+	type MaxScheduledBlocks = ConstU32<20>;
 }
 
 pub type LoggerCall = logger::Call<Test>;
diff --git a/substrate/frame/scheduler/src/tests.rs b/substrate/frame/scheduler/src/tests.rs
index 5eeef94d70b8..bb63d105d15f 100644
--- a/substrate/frame/scheduler/src/tests.rs
+++ b/substrate/frame/scheduler/src/tests.rs
@@ -1683,10 +1683,7 @@ fn on_initialize_weight_is_correct() {
 		// Will contain none
 		System::set_block_number(4);
 		let actual_weight = Scheduler::on_initialize(4);
-		assert_eq!(
-			actual_weight,
-			TestWeightInfo::service_agendas_base() + TestWeightInfo::service_agenda_base(0)
-		);
+		assert_eq!(actual_weight, TestWeightInfo::service_agendas_base());
 	});
 }
 

From 762c8162a3624b5132f2e852e0bcc556ce3cf5e8 Mon Sep 17 00:00:00 2001
From: gupnik <17176722+gupnik@users.noreply.github.com>
Date: Mon, 11 Nov 2024 16:20:38 +0530
Subject: [PATCH 03/16] Removes constraint

---
 substrate/frame/scheduler/src/lib.rs           | 18 +++++++-----------
 substrate/frame/scheduler/src/migration.rs     |  1 -
 substrate/frame/scheduler/src/tests.rs         |  3 ---
 substrate/primitives/runtime/src/traits/mod.rs |  3 ++-
 4 files changed, 9 insertions(+), 16 deletions(-)

diff --git a/substrate/frame/scheduler/src/lib.rs b/substrate/frame/scheduler/src/lib.rs
index b9a7d2c46a42..86ab00894f79 100644
--- a/substrate/frame/scheduler/src/lib.rs
+++ b/substrate/frame/scheduler/src/lib.rs
@@ -100,10 +100,7 @@ use frame_support::{
 	},
 	weights::{Weight, WeightMeter},
 };
-use frame_system::{
-	pallet_prelude::BlockNumberFor,
-	{self as system},
-};
+use frame_system::{self as system};
 use scale_info::TypeInfo;
 use sp_io::hashing::blake2_256;
 use sp_runtime::{
@@ -125,6 +122,8 @@ pub type CallOrHashOf<T> =
 pub type BoundedCallOf<T> =
 	Bounded<<T as Config>::RuntimeCall, <T as frame_system::Config>::Hashing>;
 
+pub type BlockNumberFor<T> = <<T as Config>::BlockNumberProvider as BlockNumberProvider>::BlockNumber;
+
 /// The configuration of the retry mechanism for a given task along with its current state.
 #[derive(Clone, Copy, RuntimeDebug, PartialEq, Eq, Encode, Decode, MaxEncodedLen, TypeInfo)]
 pub struct RetryConfig<Period> {
@@ -230,7 +229,7 @@ impl<T: WeightInfo> MarginalWeightInfo for T {}
 pub mod pallet {
 	use super::*;
 	use frame_support::{dispatch::PostDispatchInfo, pallet_prelude::*};
-	use frame_system::pallet_prelude::*;
+	use frame_system::pallet_prelude::{OriginFor, BlockNumberFor as SystemBlockNumberFor};
 
 	/// The in-code storage version.
 	const STORAGE_VERSION: StorageVersion = StorageVersion::new(4);
@@ -294,16 +293,13 @@ pub mod pallet {
 		type Preimages: QueryPreimage<H = Self::Hashing> + StorePreimage;
 
 		/// Provider for the block number. Normally this is the `frame_system` pallet.
-		type BlockNumberProvider: BlockNumberProvider<BlockNumber = BlockNumberFor<Self>>;
+		type BlockNumberProvider: BlockNumberProvider;
 
 		/// The maximum number of blocks that can be scheduled.
 		#[pallet::constant]
 		type MaxScheduledBlocks: Get<u32>;
 	}
 
-	#[pallet::storage]
-	pub type IncompleteSince<T: Config> = StorageValue<_, BlockNumberFor<T>>;
-
 	/// Items to be executed, indexed by the block number that they should be executed on.
 	#[pallet::storage]
 	pub type Agenda<T: Config> = StorageMap<
@@ -386,9 +382,9 @@ pub mod pallet {
 	}
 
 	#[pallet::hooks]
-	impl<T: Config> Hooks<BlockNumberFor<T>> for Pallet<T> {
+	impl<T: Config> Hooks<SystemBlockNumberFor<T>> for Pallet<T> {
 		/// Execute the scheduled calls
-		fn on_initialize(_do_not_use_local_block_number: BlockNumberFor<T>) -> Weight {
+		fn on_initialize(_do_not_use_local_block_number: SystemBlockNumberFor<T>) -> Weight {
 			let now = T::BlockNumberProvider::current_block_number();
 			let mut weight_counter = WeightMeter::with_limit(T::MaximumWeight::get());
 			Self::service_agendas(&mut weight_counter, now, u32::max_value());
diff --git a/substrate/frame/scheduler/src/migration.rs b/substrate/frame/scheduler/src/migration.rs
index a304689a120c..f3d04f215ee0 100644
--- a/substrate/frame/scheduler/src/migration.rs
+++ b/substrate/frame/scheduler/src/migration.rs
@@ -19,7 +19,6 @@
 
 use super::*;
 use frame_support::traits::OnRuntimeUpgrade;
-use frame_system::pallet_prelude::BlockNumberFor;
 
 #[cfg(feature = "try-runtime")]
 use sp_runtime::TryRuntimeError;
diff --git a/substrate/frame/scheduler/src/tests.rs b/substrate/frame/scheduler/src/tests.rs
index bb63d105d15f..cd47126dd0b2 100644
--- a/substrate/frame/scheduler/src/tests.rs
+++ b/substrate/frame/scheduler/src/tests.rs
@@ -1645,7 +1645,6 @@ fn on_initialize_weight_is_correct() {
 				TestWeightInfo::execute_dispatch_unsigned() +
 				call_weight + Weight::from_parts(4, 0)
 		);
-		assert_eq!(IncompleteSince::<Test>::get(), None);
 		assert_eq!(logger::log(), vec![(root(), 2600u32)]);
 
 		// Will include anon and anon periodic
@@ -1661,7 +1660,6 @@ fn on_initialize_weight_is_correct() {
 				TestWeightInfo::execute_dispatch_unsigned() +
 				call_weight + Weight::from_parts(2, 0)
 		);
-		assert_eq!(IncompleteSince::<Test>::get(), None);
 		assert_eq!(logger::log(), vec![(root(), 2600u32), (root(), 69u32), (root(), 42u32)]);
 
 		// Will include named only
@@ -1674,7 +1672,6 @@ fn on_initialize_weight_is_correct() {
 				TestWeightInfo::execute_dispatch_unsigned() +
 				call_weight + Weight::from_parts(1, 0)
 		);
-		assert_eq!(IncompleteSince::<Test>::get(), None);
 		assert_eq!(
 			logger::log(),
 			vec![(root(), 2600u32), (root(), 69u32), (root(), 42u32), (root(), 3u32)]
diff --git a/substrate/primitives/runtime/src/traits/mod.rs b/substrate/primitives/runtime/src/traits/mod.rs
index e6906cdb3877..74b948fc5d18 100644
--- a/substrate/primitives/runtime/src/traits/mod.rs
+++ b/substrate/primitives/runtime/src/traits/mod.rs
@@ -2348,7 +2348,8 @@ pub trait BlockNumberProvider {
 		+ TypeInfo
 		+ Debug
 		+ MaxEncodedLen
-		+ Copy;
+		+ Copy
+		+ EncodeLike;
 
 	/// Returns the current block number.
 	///

From 86701cfed637a9cf1236ec666940bfc018f0565e Mon Sep 17 00:00:00 2001
From: gupnik <17176722+gupnik@users.noreply.github.com>
Date: Wed, 13 Nov 2024 09:52:13 +0530
Subject: [PATCH 04/16] Updates benchmarks

---
 substrate/frame/scheduler/src/benchmarking.rs | 74 ++++++++++++++-----
 1 file changed, 54 insertions(+), 20 deletions(-)

diff --git a/substrate/frame/scheduler/src/benchmarking.rs b/substrate/frame/scheduler/src/benchmarking.rs
index d0a14fc73d64..2bbdd04e1cb4 100644
--- a/substrate/frame/scheduler/src/benchmarking.rs
+++ b/substrate/frame/scheduler/src/benchmarking.rs
@@ -22,17 +22,20 @@ use alloc::vec;
 use frame_benchmarking::v1::{account, benchmarks, BenchmarkError};
 use frame_support::{
 	ensure,
+	testing_prelude::*,
 	traits::{schedule::Priority, BoundedInline},
 	weights::WeightMeter,
 };
-use frame_system::{pallet_prelude::BlockNumberFor, RawOrigin};
+use frame_system::RawOrigin;
 
 use crate::Pallet as Scheduler;
 use frame_system::{Call as SystemCall, EventRecord};
 
 const SEED: u32 = 0;
 
-const BLOCK_NUMBER: u32 = 2;
+fn block_number<T: Config>() -> u32 {
+	T::MaxScheduledBlocks::get()
+}
 
 type SystemOrigin<T> = <T as frame_system::Config>::RuntimeOrigin;
 
@@ -44,6 +47,15 @@ fn assert_last_event<T: Config>(generic_event: <T as Config>::RuntimeEvent) {
 	assert_eq!(event, &system_event);
 }
 
+fn fill_queue<T: Config>(n: u32) {
+	let mut vec = Vec::<BlockNumberFor<T>>::new();
+	for i in 0..n {
+		vec.push(i.into());
+	}
+	let bounded_vec = BoundedVec::try_from(vec).unwrap();
+	Queue::<T>::put::<BoundedVec<_, _>>(bounded_vec);
+}
+
 /// Add `n` items to the schedule.
 ///
 /// For `resolved`:
@@ -52,7 +64,7 @@ fn assert_last_event<T: Config>(generic_event: <T as Config>::RuntimeEvent) {
 /// - `Some(true)`: hash resolves into call if possible, plain call otherwise
 /// - `Some(false)`: plain call
 fn fill_schedule<T: Config>(
-	when: frame_system::pallet_prelude::BlockNumberFor<T>,
+	when: BlockNumberFor<T>,
 	n: u32,
 ) -> Result<(), &'static str> {
 	let t = DispatchTime::At(when);
@@ -137,17 +149,19 @@ fn make_origin<T: Config>(signed: bool) -> <T as Config>::PalletsOrigin {
 benchmarks! {
 	// `service_agendas` when no work is done.
 	service_agendas_base {
-		let now = BlockNumberFor::<T>::from(BLOCK_NUMBER);
-		IncompleteSince::<T>::put(now - One::one());
+		let now = BlockNumberFor::<T>::from(block_number::<T>());
+		Queue::<T>::put::<BoundedVec<_, _>>(bounded_vec![now + One::one()]);
 	}: {
 		Scheduler::<T>::service_agendas(&mut WeightMeter::new(), now, 0);
 	} verify {
-		assert_eq!(IncompleteSince::<T>::get(), Some(now - One::one()));
+		let expected: BoundedVec<BlockNumberFor<T>, T::MaxScheduledBlocks> =
+			bounded_vec![now + One::one()];
+		assert_eq!(Queue::<T>::get(), expected);
 	}
 
 	// `service_agenda` when no work is done.
 	service_agenda_base {
-		let now = BLOCK_NUMBER.into();
+		let now = block_number::<T>().into();
 		let s in 0 .. T::MaxScheduledPerBlock::get();
 		fill_schedule::<T>(now, s)?;
 		let mut executed = 0;
@@ -160,7 +174,7 @@ benchmarks! {
 	// `service_task` when the task is a non-periodic, non-named, non-fetched call which is not
 	// dispatched (e.g. due to being overweight).
 	service_task_base {
-		let now = BLOCK_NUMBER.into();
+		let now = block_number::<T>().into();
 		let task = make_task::<T>(false, false, false, None, 0);
 		// prevent any tasks from actually being executed as we only want the surrounding weight.
 		let mut counter = WeightMeter::with_limit(Weight::zero());
@@ -178,7 +192,7 @@ benchmarks! {
 	}]
 	service_task_fetched {
 		let s in (BoundedInline::bound() as u32) .. (T::Preimages::MAX_LENGTH as u32);
-		let now = BLOCK_NUMBER.into();
+		let now = block_number::<T>().into();
 		let task = make_task::<T>(false, false, false, Some(s), 0);
 		// prevent any tasks from actually being executed as we only want the surrounding weight.
 		let mut counter = WeightMeter::with_limit(Weight::zero());
@@ -190,7 +204,7 @@ benchmarks! {
 	// `service_task` when the task is a non-periodic, named, non-fetched call which is not
 	// dispatched (e.g. due to being overweight).
 	service_task_named {
-		let now = BLOCK_NUMBER.into();
+		let now = block_number::<T>().into();
 		let task = make_task::<T>(false, true, false, None, 0);
 		// prevent any tasks from actually being executed as we only want the surrounding weight.
 		let mut counter = WeightMeter::with_limit(Weight::zero());
@@ -202,7 +216,7 @@ benchmarks! {
 	// `service_task` when the task is a periodic, non-named, non-fetched call which is not
 	// dispatched (e.g. due to being overweight).
 	service_task_periodic {
-		let now = BLOCK_NUMBER.into();
+		let now = block_number::<T>().into();
 		let task = make_task::<T>(true, false, false, None, 0);
 		// prevent any tasks from actually being executed as we only want the surrounding weight.
 		let mut counter = WeightMeter::with_limit(Weight::zero());
@@ -235,26 +249,32 @@ benchmarks! {
 
 	schedule {
 		let s in 0 .. (T::MaxScheduledPerBlock::get() - 1);
-		let when = BLOCK_NUMBER.into();
+		let when = block_number::<T>().into();
 		let periodic = Some((BlockNumberFor::<T>::one(), 100));
 		let priority = 0;
 		// Essentially a no-op call.
 		let call = Box::new(SystemCall::set_storage { items: vec![] }.into());
 
 		fill_schedule::<T>(when, s)?;
+		fill_queue::<T>(T::MaxScheduledBlocks::get() - 1);
 	}: _(RawOrigin::Root, when, periodic, priority, call)
 	verify {
 		ensure!(
 			Agenda::<T>::get(when).len() == (s + 1) as usize,
 			"didn't add to schedule"
 		);
+		ensure!(
+			Queue::<T>::get().len() == T::MaxScheduledBlocks::get() as usize,
+			"didn't add to queue"
+		);
 	}
 
 	cancel {
 		let s in 1 .. T::MaxScheduledPerBlock::get();
-		let when = BLOCK_NUMBER.into();
+		let when = (block_number::<T>() - 1).into();
 
 		fill_schedule::<T>(when, s)?;
+		fill_queue::<T>(T::MaxScheduledBlocks::get());
 		assert_eq!(Agenda::<T>::get(when).len(), s as usize);
 		let schedule_origin =
 			T::ScheduleOrigin::try_successful_origin().map_err(|_| BenchmarkError::Weightless)?;
@@ -273,31 +293,41 @@ benchmarks! {
 			s > 1 || Agenda::<T>::get(when).len() == 0,
 			"remove from schedule if only 1 task scheduled for `when`"
 		);
+		ensure!(
+			s > 1 || Queue::<T>::get().len() == T::MaxScheduledBlocks::get() as usize - 1,
+			"didn't remove from queue"
+		);
 	}
 
 	schedule_named {
 		let s in 0 .. (T::MaxScheduledPerBlock::get() - 1);
 		let id = u32_to_name(s);
-		let when = BLOCK_NUMBER.into();
+		let when = block_number::<T>().into();
 		let periodic = Some((BlockNumberFor::<T>::one(), 100));
 		let priority = 0;
 		// Essentially a no-op call.
 		let call = Box::new(SystemCall::set_storage { items: vec![] }.into());
 
 		fill_schedule::<T>(when, s)?;
+		fill_queue::<T>(T::MaxScheduledBlocks::get() - 1);
 	}: _(RawOrigin::Root, id, when, periodic, priority, call)
 	verify {
 		ensure!(
 			Agenda::<T>::get(when).len() == (s + 1) as usize,
 			"didn't add to schedule"
 		);
+		ensure!(
+			Queue::<T>::get().len() == T::MaxScheduledBlocks::get() as usize,
+			"didn't add to queue"
+		);
 	}
 
 	cancel_named {
 		let s in 1 .. T::MaxScheduledPerBlock::get();
-		let when = BLOCK_NUMBER.into();
+		let when = (block_number::<T>() - 1).into();
 
 		fill_schedule::<T>(when, s)?;
+		fill_queue::<T>(T::MaxScheduledBlocks::get());
 	}: _(RawOrigin::Root, u32_to_name(0))
 	verify {
 		ensure!(
@@ -313,11 +343,15 @@ benchmarks! {
 			s > 1 || Agenda::<T>::get(when).len() == 0,
 			"remove from schedule if only 1 task scheduled for `when`"
 		);
+		ensure!(
+			s > 1 || Queue::<T>::get().len() == T::MaxScheduledBlocks::get() as usize - 1,
+			"didn't remove from queue"
+		);
 	}
 
 	schedule_retry {
 		let s in 1 .. T::MaxScheduledPerBlock::get();
-		let when = BLOCK_NUMBER.into();
+		let when = block_number::<T>().into();
 
 		fill_schedule::<T>(when, s)?;
 		let name = u32_to_name(s - 1);
@@ -341,7 +375,7 @@ benchmarks! {
 
 	set_retry {
 		let s = T::MaxScheduledPerBlock::get();
-		let when = BLOCK_NUMBER.into();
+		let when = block_number::<T>().into();
 
 		fill_schedule::<T>(when, s)?;
 		let name = u32_to_name(s - 1);
@@ -361,7 +395,7 @@ benchmarks! {
 
 	set_retry_named {
 		let s = T::MaxScheduledPerBlock::get();
-		let when = BLOCK_NUMBER.into();
+		let when = block_number::<T>().into();
 
 		fill_schedule::<T>(when, s)?;
 		let name = u32_to_name(s - 1);
@@ -381,7 +415,7 @@ benchmarks! {
 
 	cancel_retry {
 		let s = T::MaxScheduledPerBlock::get();
-		let when = BLOCK_NUMBER.into();
+		let when = block_number::<T>().into();
 
 		fill_schedule::<T>(when, s)?;
 		let name = u32_to_name(s - 1);
@@ -399,7 +433,7 @@ benchmarks! {
 
 	cancel_retry_named {
 		let s = T::MaxScheduledPerBlock::get();
-		let when = BLOCK_NUMBER.into();
+		let when = block_number::<T>().into();
 
 		fill_schedule::<T>(when, s)?;
 		let name = u32_to_name(s - 1);

From 27d1fa1473b6a51ebc74f116d7abfcb875b1e1d7 Mon Sep 17 00:00:00 2001
From: gupnik <17176722+gupnik@users.noreply.github.com>
Date: Thu, 14 Nov 2024 10:03:43 +0530
Subject: [PATCH 05/16] Adds migration

---
 substrate/frame/scheduler/src/migration.rs | 72 ++++++++++++++++++++++
 1 file changed, 72 insertions(+)

diff --git a/substrate/frame/scheduler/src/migration.rs b/substrate/frame/scheduler/src/migration.rs
index f3d04f215ee0..2c3e840ec44e 100644
--- a/substrate/frame/scheduler/src/migration.rs
+++ b/substrate/frame/scheduler/src/migration.rs
@@ -560,3 +560,75 @@ mod test {
 		system::RawOrigin::Signed(i).into()
 	}
 }
+
+pub mod v5 {
+	use super::*;
+	use frame_support::{migrations::VersionedMigration, traits::UncheckedOnRuntimeUpgrade, pallet_prelude::*};
+
+	#[frame_support::storage_alias]
+	pub(crate) type IncompleteSince<T: Config> = StorageValue<Pallet<T>, BlockNumberFor<T>>;
+
+	pub struct VersionUncheckedMigrateV4ToV5<T>(core::marker::PhantomData<T>);
+	impl<T: Config> UncheckedOnRuntimeUpgrade for VersionUncheckedMigrateV4ToV5<T> {
+		fn on_runtime_upgrade() -> Weight {
+			IncompleteSince::<T>::kill();
+			let mut weight = T::DbWeight::get().writes(1);
+			
+			let mut queue = vec![];
+			Agenda::<T>::iter().for_each(|(k, _)| {
+				queue.push(k);
+				weight.saturating_accrue(T::DbWeight::get().reads(1));
+			});
+			queue.sort_unstable();
+			queue.dedup();
+
+			let queue = BoundedVec::<BlockNumberFor<T>, T::MaxScheduledBlocks>::try_from(queue).unwrap();
+			Queue::<T>::put(queue);
+			weight.saturating_accrue(T::DbWeight::get().writes(1));
+
+			weight
+		}
+
+		#[cfg(feature = "try-runtime")]
+		fn post_upgrade(_state: Vec<u8>) -> Result<(), TryRuntimeError> {
+			frame_support::ensure!(
+				IncompleteSince::<T>::get().is_none(),
+				"IncompleteSince is not empty after the migration"
+			);
+			Ok(())
+		}
+	}
+
+	pub type MigrateV4ToV5<T> = VersionedMigration<
+		4,
+		5,
+		VersionUncheckedMigrateV4ToV5<T>,
+		Pallet<T>,
+		<T as frame_system::Config>::DbWeight,
+	>;
+}
+
+#[cfg(test)]
+pub mod test {
+	use super::*;
+	use crate::mock::*;
+	use crate::migration::v5::IncompleteSince;
+	use frame_support::testing_prelude::*;
+
+	#[test]
+	fn migration_v4_to_v5_works() {
+		new_test_ext().execute_with(|| {
+			StorageVersion::new(4).put::<Scheduler>();
+			IncompleteSince::<Test>::put(1);
+			Agenda::<Test>::insert::<u64, BoundedVec<Option<ScheduledOf<Test>>, <Test as Config>::MaxScheduledPerBlock>>(2, bounded_vec![None]);
+			Agenda::<Test>::insert::<u64, BoundedVec<Option<ScheduledOf<Test>>, <Test as Config>::MaxScheduledPerBlock>>(3, bounded_vec![None]);
+
+			v5::MigrateV4ToV5::<Test>::on_runtime_upgrade();
+
+			assert_eq!(StorageVersion::get::<Scheduler>(), 5);
+			assert_eq!(IncompleteSince::<Test>::get(), None);
+			let queue = BoundedVec::<BlockNumberFor<Test>, <Test as Config>::MaxScheduledBlocks>::try_from(vec![2, 3]).unwrap();
+			assert_eq!(Queue::<Test>::get(), queue);
+		});
+	}
+}

From c79900cf525dcabef94dba11d6a6d5393d6ece2b Mon Sep 17 00:00:00 2001
From: gupnik <17176722+gupnik@users.noreply.github.com>
Date: Thu, 14 Nov 2024 10:04:25 +0530
Subject: [PATCH 06/16] FMT

---
 substrate/frame/scheduler/src/benchmarking.rs |  5 +---
 substrate/frame/scheduler/src/lib.rs          |  5 ++--
 substrate/frame/scheduler/src/migration.rs    | 28 +++++++++++++------
 3 files changed, 24 insertions(+), 14 deletions(-)

diff --git a/substrate/frame/scheduler/src/benchmarking.rs b/substrate/frame/scheduler/src/benchmarking.rs
index 2bbdd04e1cb4..20e22774d31e 100644
--- a/substrate/frame/scheduler/src/benchmarking.rs
+++ b/substrate/frame/scheduler/src/benchmarking.rs
@@ -63,10 +63,7 @@ fn fill_queue<T: Config>(n: u32) {
 /// - `None`: aborted (hash without preimage)
 /// - `Some(true)`: hash resolves into call if possible, plain call otherwise
 /// - `Some(false)`: plain call
-fn fill_schedule<T: Config>(
-	when: BlockNumberFor<T>,
-	n: u32,
-) -> Result<(), &'static str> {
+fn fill_schedule<T: Config>(when: BlockNumberFor<T>, n: u32) -> Result<(), &'static str> {
 	let t = DispatchTime::At(when);
 	let origin: <T as Config>::PalletsOrigin = frame_system::RawOrigin::Root.into();
 	for i in 0..n {
diff --git a/substrate/frame/scheduler/src/lib.rs b/substrate/frame/scheduler/src/lib.rs
index 86ab00894f79..cc4420d4a65d 100644
--- a/substrate/frame/scheduler/src/lib.rs
+++ b/substrate/frame/scheduler/src/lib.rs
@@ -122,7 +122,8 @@ pub type CallOrHashOf<T> =
 pub type BoundedCallOf<T> =
 	Bounded<<T as Config>::RuntimeCall, <T as frame_system::Config>::Hashing>;
 
-pub type BlockNumberFor<T> = <<T as Config>::BlockNumberProvider as BlockNumberProvider>::BlockNumber;
+pub type BlockNumberFor<T> =
+	<<T as Config>::BlockNumberProvider as BlockNumberProvider>::BlockNumber;
 
 /// The configuration of the retry mechanism for a given task along with its current state.
 #[derive(Clone, Copy, RuntimeDebug, PartialEq, Eq, Encode, Decode, MaxEncodedLen, TypeInfo)]
@@ -229,7 +230,7 @@ impl<T: WeightInfo> MarginalWeightInfo for T {}
 pub mod pallet {
 	use super::*;
 	use frame_support::{dispatch::PostDispatchInfo, pallet_prelude::*};
-	use frame_system::pallet_prelude::{OriginFor, BlockNumberFor as SystemBlockNumberFor};
+	use frame_system::pallet_prelude::{BlockNumberFor as SystemBlockNumberFor, OriginFor};
 
 	/// The in-code storage version.
 	const STORAGE_VERSION: StorageVersion = StorageVersion::new(4);
diff --git a/substrate/frame/scheduler/src/migration.rs b/substrate/frame/scheduler/src/migration.rs
index 2c3e840ec44e..acc84adf666c 100644
--- a/substrate/frame/scheduler/src/migration.rs
+++ b/substrate/frame/scheduler/src/migration.rs
@@ -563,7 +563,9 @@ mod test {
 
 pub mod v5 {
 	use super::*;
-	use frame_support::{migrations::VersionedMigration, traits::UncheckedOnRuntimeUpgrade, pallet_prelude::*};
+	use frame_support::{
+		migrations::VersionedMigration, pallet_prelude::*, traits::UncheckedOnRuntimeUpgrade,
+	};
 
 	#[frame_support::storage_alias]
 	pub(crate) type IncompleteSince<T: Config> = StorageValue<Pallet<T>, BlockNumberFor<T>>;
@@ -573,7 +575,7 @@ pub mod v5 {
 		fn on_runtime_upgrade() -> Weight {
 			IncompleteSince::<T>::kill();
 			let mut weight = T::DbWeight::get().writes(1);
-			
+
 			let mut queue = vec![];
 			Agenda::<T>::iter().for_each(|(k, _)| {
 				queue.push(k);
@@ -582,7 +584,8 @@ pub mod v5 {
 			queue.sort_unstable();
 			queue.dedup();
 
-			let queue = BoundedVec::<BlockNumberFor<T>, T::MaxScheduledBlocks>::try_from(queue).unwrap();
+			let queue =
+				BoundedVec::<BlockNumberFor<T>, T::MaxScheduledBlocks>::try_from(queue).unwrap();
 			Queue::<T>::put(queue);
 			weight.saturating_accrue(T::DbWeight::get().writes(1));
 
@@ -611,8 +614,7 @@ pub mod v5 {
 #[cfg(test)]
 pub mod test {
 	use super::*;
-	use crate::mock::*;
-	use crate::migration::v5::IncompleteSince;
+	use crate::{migration::v5::IncompleteSince, mock::*};
 	use frame_support::testing_prelude::*;
 
 	#[test]
@@ -620,14 +622,24 @@ pub mod test {
 		new_test_ext().execute_with(|| {
 			StorageVersion::new(4).put::<Scheduler>();
 			IncompleteSince::<Test>::put(1);
-			Agenda::<Test>::insert::<u64, BoundedVec<Option<ScheduledOf<Test>>, <Test as Config>::MaxScheduledPerBlock>>(2, bounded_vec![None]);
-			Agenda::<Test>::insert::<u64, BoundedVec<Option<ScheduledOf<Test>>, <Test as Config>::MaxScheduledPerBlock>>(3, bounded_vec![None]);
+			Agenda::<Test>::insert::<
+				u64,
+				BoundedVec<Option<ScheduledOf<Test>>, <Test as Config>::MaxScheduledPerBlock>,
+			>(2, bounded_vec![None]);
+			Agenda::<Test>::insert::<
+				u64,
+				BoundedVec<Option<ScheduledOf<Test>>, <Test as Config>::MaxScheduledPerBlock>,
+			>(3, bounded_vec![None]);
 
 			v5::MigrateV4ToV5::<Test>::on_runtime_upgrade();
 
 			assert_eq!(StorageVersion::get::<Scheduler>(), 5);
 			assert_eq!(IncompleteSince::<Test>::get(), None);
-			let queue = BoundedVec::<BlockNumberFor<Test>, <Test as Config>::MaxScheduledBlocks>::try_from(vec![2, 3]).unwrap();
+			let queue =
+				BoundedVec::<BlockNumberFor<Test>, <Test as Config>::MaxScheduledBlocks>::try_from(
+					vec![2, 3],
+				)
+				.unwrap();
 			assert_eq!(Queue::<Test>::get(), queue);
 		});
 	}

From 622805d69fc9088de6a92144e83d3a77f29f40e2 Mon Sep 17 00:00:00 2001
From: gupnik <17176722+gupnik@users.noreply.github.com>
Date: Thu, 14 Nov 2024 10:09:44 +0530
Subject: [PATCH 07/16] Adds PrDoc

---
 prdoc/pr_6362.prdoc | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)
 create mode 100644 prdoc/pr_6362.prdoc

diff --git a/prdoc/pr_6362.prdoc b/prdoc/pr_6362.prdoc
new file mode 100644
index 000000000000..9ddee2037479
--- /dev/null
+++ b/prdoc/pr_6362.prdoc
@@ -0,0 +1,23 @@
+title: Update Scheduler to Support Relay Chain Block Number Provider
+
+doc:
+  - audience: Runtime Dev
+    description: |
+      This PR adds the ability for the Scheduler pallet to specify its source of the block number.
+      This is needed for the scheduler pallet to work on a parachain which does not produce blocks
+      on a regular schedule, thus can use the relay chain as a block provider. Because blocks are
+      not produced regularly, we cannot make the assumption that the block number increases 
+      monotonically, and thus have a new logic to handle multiple blocks with valid agenda passed 
+      between them.
+
+      This change is backwards compatible:
+      1. If the `BlockNumberProvider` continues to use the system pallet's block number
+      2. When a pallet deployed on the relay chain is moved to a parachain, but still uses the 
+      relay chain's block number
+
+      However, we would need migrations if the deployed pallets are upgraded on an existing parachain,
+      and the `BlockNumberProvider` uses the relay chain block number.  
+
+crates:
+  - name: pallet-scheduler
+    bump: major

From abbd346bbe1e6405012a38f98ddff1e350f113cd Mon Sep 17 00:00:00 2001
From: gupnik <17176722+gupnik@users.noreply.github.com>
Date: Thu, 14 Nov 2024 10:20:19 +0530
Subject: [PATCH 08/16] Updates PrDoc

---
 prdoc/pr_6362.prdoc | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/prdoc/pr_6362.prdoc b/prdoc/pr_6362.prdoc
index 9ddee2037479..57586d1423d4 100644
--- a/prdoc/pr_6362.prdoc
+++ b/prdoc/pr_6362.prdoc
@@ -7,10 +7,10 @@ doc:
       This is needed for the scheduler pallet to work on a parachain which does not produce blocks
       on a regular schedule, thus can use the relay chain as a block provider. Because blocks are
       not produced regularly, we cannot make the assumption that the block number increases 
-      monotonically, and thus have a new logic to handle multiple blocks with valid agenda passed 
-      between them.
+      monotonically, and thus have a new logic via a `Queue` to handle multiple blocks with valid 
+      agenda passed between them.
 
-      This change is backwards compatible:
+      This change only needs a migration for the `Queue`:
       1. If the `BlockNumberProvider` continues to use the system pallet's block number
       2. When a pallet deployed on the relay chain is moved to a parachain, but still uses the 
       relay chain's block number

From 813e5965178dcff3f5ba093553ae80776e5e2e89 Mon Sep 17 00:00:00 2001
From: gupnik <17176722+gupnik@users.noreply.github.com>
Date: Fri, 15 Nov 2024 15:16:47 +0530
Subject: [PATCH 09/16] Fixes

---
 substrate/frame/scheduler/src/benchmarking.rs | 2 +-
 substrate/frame/scheduler/src/migration.rs    | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/substrate/frame/scheduler/src/benchmarking.rs b/substrate/frame/scheduler/src/benchmarking.rs
index 20e22774d31e..0136d770285a 100644
--- a/substrate/frame/scheduler/src/benchmarking.rs
+++ b/substrate/frame/scheduler/src/benchmarking.rs
@@ -22,11 +22,11 @@ use alloc::vec;
 use frame_benchmarking::v1::{account, benchmarks, BenchmarkError};
 use frame_support::{
 	ensure,
-	testing_prelude::*,
 	traits::{schedule::Priority, BoundedInline},
 	weights::WeightMeter,
 };
 use frame_system::RawOrigin;
+use sp_runtime::bounded_vec;
 
 use crate::Pallet as Scheduler;
 use frame_system::{Call as SystemCall, EventRecord};
diff --git a/substrate/frame/scheduler/src/migration.rs b/substrate/frame/scheduler/src/migration.rs
index acc84adf666c..3879206d8330 100644
--- a/substrate/frame/scheduler/src/migration.rs
+++ b/substrate/frame/scheduler/src/migration.rs
@@ -616,6 +616,7 @@ pub mod test {
 	use super::*;
 	use crate::{migration::v5::IncompleteSince, mock::*};
 	use frame_support::testing_prelude::*;
+	use scale_info::prelude::vec;
 
 	#[test]
 	fn migration_v4_to_v5_works() {

From 8c40f24bafdaffd6d2bb628e708e78af78012e83 Mon Sep 17 00:00:00 2001
From: gupnik <17176722+gupnik@users.noreply.github.com>
Date: Fri, 15 Nov 2024 15:39:22 +0530
Subject: [PATCH 10/16] Adds MaxStaleTaskAge

---
 .../collectives-westend/src/lib.rs            |  2 ++
 polkadot/runtime/rococo/src/lib.rs            |  2 ++
 polkadot/runtime/westend/src/lib.rs           |  2 ++
 substrate/bin/node/runtime/src/lib.rs         |  1 +
 substrate/frame/democracy/src/tests.rs        |  1 +
 substrate/frame/referenda/src/mock.rs         |  1 +
 substrate/frame/scheduler/src/lib.rs          | 14 ++++++++---
 substrate/frame/scheduler/src/mock.rs         |  5 +++-
 substrate/frame/scheduler/src/tests.rs        | 23 +++++++++++++++++++
 9 files changed, 47 insertions(+), 4 deletions(-)

diff --git a/cumulus/parachains/runtimes/collectives/collectives-westend/src/lib.rs b/cumulus/parachains/runtimes/collectives/collectives-westend/src/lib.rs
index f135c1463276..62927807afb8 100644
--- a/cumulus/parachains/runtimes/collectives/collectives-westend/src/lib.rs
+++ b/cumulus/parachains/runtimes/collectives/collectives-westend/src/lib.rs
@@ -611,6 +611,7 @@ parameter_types! {
 parameter_types! {
 	pub const MaxScheduledPerBlock: u32 = 200;
 	pub const MaxScheduledBlocks: u32 = 200;
+	pub const MaxStaleTaskAge: u64 = 10;
 }
 
 impl pallet_scheduler::Config for Runtime {
@@ -626,6 +627,7 @@ impl pallet_scheduler::Config for Runtime {
 	type Preimages = Preimage;
 	type BlockNumberProvider = frame_system::Pallet<Runtime>;
 	type MaxScheduledBlocks = MaxScheduledBlocks;
+	type MaxStaleTaskAge = MaxStaleTaskAge;
 }
 
 parameter_types! {
diff --git a/polkadot/runtime/rococo/src/lib.rs b/polkadot/runtime/rococo/src/lib.rs
index f2db0e4334aa..840408979c5f 100644
--- a/polkadot/runtime/rococo/src/lib.rs
+++ b/polkadot/runtime/rococo/src/lib.rs
@@ -232,6 +232,7 @@ parameter_types! {
 		BlockWeights::get().max_block;
 	pub const MaxScheduledPerBlock: u32 = 50;
 	pub const MaxScheduledBlocks: u32 = 50;
+	pub const MaxStaleTaskAge: u64 = 10;
 	pub const NoPreimagePostponement: Option<u32> = Some(10);
 }
 
@@ -334,6 +335,7 @@ impl pallet_scheduler::Config for Runtime {
 	type Preimages = Preimage;
 	type BlockNumberProvider = frame_system::Pallet<Runtime>;
 	type MaxScheduledBlocks = MaxScheduledBlocks;
+	type MaxStaleTaskAge = MaxStaleTaskAge;
 }
 
 parameter_types! {
diff --git a/polkadot/runtime/westend/src/lib.rs b/polkadot/runtime/westend/src/lib.rs
index 86b612fbdc61..c05ce1228d41 100644
--- a/polkadot/runtime/westend/src/lib.rs
+++ b/polkadot/runtime/westend/src/lib.rs
@@ -233,6 +233,7 @@ parameter_types! {
 		BlockWeights::get().max_block;
 	pub const MaxScheduledPerBlock: u32 = 50;
 	pub const MaxScheduledBlocks: u32 = 50;
+	pub const MaxStaleTaskAge: u64 = 10;
 	pub const NoPreimagePostponement: Option<u32> = Some(10);
 }
 
@@ -251,6 +252,7 @@ impl pallet_scheduler::Config for Runtime {
 	type Preimages = Preimage;
 	type BlockNumberProvider = frame_system::Pallet<Runtime>;
 	type MaxScheduledBlocks = MaxScheduledBlocks;
+	type MaxStaleTaskAge = MaxStaleTaskAge;
 }
 
 parameter_types! {
diff --git a/substrate/bin/node/runtime/src/lib.rs b/substrate/bin/node/runtime/src/lib.rs
index e0c7b051826f..d49d91563762 100644
--- a/substrate/bin/node/runtime/src/lib.rs
+++ b/substrate/bin/node/runtime/src/lib.rs
@@ -504,6 +504,7 @@ impl pallet_scheduler::Config for Runtime {
 	type MaxScheduledBlocks = ConstU32<512>;
 	#[cfg(not(feature = "runtime-benchmarks"))]
 	type MaxScheduledBlocks = ConstU32<50>;
+	type MaxStaleTaskAge = ConstU64<10>;
 }
 
 impl pallet_glutton::Config for Runtime {
diff --git a/substrate/frame/democracy/src/tests.rs b/substrate/frame/democracy/src/tests.rs
index 6a09a054452e..3d88f49a4138 100644
--- a/substrate/frame/democracy/src/tests.rs
+++ b/substrate/frame/democracy/src/tests.rs
@@ -108,6 +108,7 @@ impl pallet_scheduler::Config for Test {
 	type Preimages = ();
 	type BlockNumberProvider = frame_system::Pallet<Test>;
 	type MaxScheduledBlocks = ConstU32<100>;
+	type MaxStaleTaskAge = ConstU64<10>;
 }
 
 #[derive_impl(pallet_balances::config_preludes::TestDefaultConfig)]
diff --git a/substrate/frame/referenda/src/mock.rs b/substrate/frame/referenda/src/mock.rs
index e45353408d76..c6ef49fdb146 100644
--- a/substrate/frame/referenda/src/mock.rs
+++ b/substrate/frame/referenda/src/mock.rs
@@ -83,6 +83,7 @@ impl pallet_scheduler::Config for Test {
 	type Preimages = Preimage;
 	type BlockNumberProvider = frame_system::Pallet<Test>;
 	type MaxScheduledBlocks = ConstU32<100>;
+	type MaxStaleTaskAge = ConstU64<10>;
 }
 #[derive_impl(pallet_balances::config_preludes::TestDefaultConfig)]
 impl pallet_balances::Config for Test {
diff --git a/substrate/frame/scheduler/src/lib.rs b/substrate/frame/scheduler/src/lib.rs
index cc4420d4a65d..ad5c522b5945 100644
--- a/substrate/frame/scheduler/src/lib.rs
+++ b/substrate/frame/scheduler/src/lib.rs
@@ -299,6 +299,10 @@ pub mod pallet {
 		/// The maximum number of blocks that can be scheduled.
 		#[pallet::constant]
 		type MaxScheduledBlocks: Get<u32>;
+
+		/// The maximum number of blocks that a task can be stale for.
+		#[pallet::constant]
+		type MaxStaleTaskAge: Get<BlockNumberFor<Self>>;
 	}
 
 	/// Items to be executed, indexed by the block number that they should be executed on.
@@ -1192,9 +1196,13 @@ impl<T: Config> Pallet<T> {
 		let mut index = 0;
 		while index < end_index {
 			let when = queue[index];
-			let mut executed = 0;
-			if !Self::service_agenda(weight, &mut executed, now, when, max) {
-				break;
+			if when < now.saturating_sub(T::MaxStaleTaskAge::get()) {
+				Agenda::<T>::remove(when);
+			} else {
+				let mut executed = 0;
+				if !Self::service_agenda(weight, &mut executed, now, when, max) {
+					break;
+				}
 			}
 			index.saturating_inc();
 		}
diff --git a/substrate/frame/scheduler/src/mock.rs b/substrate/frame/scheduler/src/mock.rs
index 73441d44f308..18357c0c1498 100644
--- a/substrate/frame/scheduler/src/mock.rs
+++ b/substrate/frame/scheduler/src/mock.rs
@@ -22,7 +22,9 @@ use super::*;
 use crate as scheduler;
 use frame_support::{
 	derive_impl, ord_parameter_types, parameter_types,
-	traits::{ConstU32, Contains, EitherOfDiverse, EqualPrivilegeOnly, OnFinalize, OnInitialize},
+	traits::{
+		ConstU32, ConstU64, Contains, EitherOfDiverse, EqualPrivilegeOnly, OnFinalize, OnInitialize,
+	},
 };
 use frame_system::{EnsureRoot, EnsureSignedBy};
 use sp_runtime::{BuildStorage, Perbill};
@@ -229,6 +231,7 @@ impl Config for Test {
 	type Preimages = Preimage;
 	type BlockNumberProvider = frame_system::Pallet<Self>;
 	type MaxScheduledBlocks = ConstU32<20>;
+	type MaxStaleTaskAge = ConstU64<10>;
 }
 
 pub type LoggerCall = logger::Call<Test>;
diff --git a/substrate/frame/scheduler/src/tests.rs b/substrate/frame/scheduler/src/tests.rs
index cd47126dd0b2..fa77dcbdeeb6 100644
--- a/substrate/frame/scheduler/src/tests.rs
+++ b/substrate/frame/scheduler/src/tests.rs
@@ -3066,3 +3066,26 @@ fn basic_scheduling_with_skipped_blocks_works() {
 		assert_eq!(logger::log(), vec![(root(), 42u32)]);
 	});
 }
+
+#[test]
+fn stale_task_is_removed() {
+	new_test_ext().execute_with(|| {
+		let call =
+			RuntimeCall::Logger(LoggerCall::log { i: 42, weight: Weight::from_parts(10, 0) });
+
+		// Schedule call to be executed at the 4th block
+		assert_ok!(Scheduler::do_schedule(
+			DispatchTime::At(4),
+			None,
+			127,
+			root(),
+			Preimage::bound(call).unwrap()
+		));
+		assert!(Agenda::<Test>::get(4).len() == 1);
+		assert!(Queue::<Test>::get().contains(&4));
+
+		go_to_block(20);
+		assert!(Agenda::<Test>::get(4).is_empty());
+		assert!(!Queue::<Test>::get().contains(&4));
+	})
+}

From b905628213cd7d3581d0c520e4764d3928923704 Mon Sep 17 00:00:00 2001
From: gupnik <17176722+gupnik@users.noreply.github.com>
Date: Fri, 15 Nov 2024 16:01:07 +0530
Subject: [PATCH 11/16] Fixes

---
 substrate/frame/scheduler/src/benchmarking.rs | 5 +++--
 substrate/frame/scheduler/src/migration.rs    | 2 +-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/substrate/frame/scheduler/src/benchmarking.rs b/substrate/frame/scheduler/src/benchmarking.rs
index 0136d770285a..8cb622f8e59d 100644
--- a/substrate/frame/scheduler/src/benchmarking.rs
+++ b/substrate/frame/scheduler/src/benchmarking.rs
@@ -22,6 +22,7 @@ use alloc::vec;
 use frame_benchmarking::v1::{account, benchmarks, BenchmarkError};
 use frame_support::{
 	ensure,
+	storage::bounded_vec::BoundedVec,
 	traits::{schedule::Priority, BoundedInline},
 	weights::WeightMeter,
 };
@@ -147,12 +148,12 @@ benchmarks! {
 	// `service_agendas` when no work is done.
 	service_agendas_base {
 		let now = BlockNumberFor::<T>::from(block_number::<T>());
-		Queue::<T>::put::<BoundedVec<_, _>>(bounded_vec![now + One::one()]);
+		Queue::<T>::put::<BoundedVec<_, _>>(BoundedVec::try_from(vec![now + One::one()]).unwrap());
 	}: {
 		Scheduler::<T>::service_agendas(&mut WeightMeter::new(), now, 0);
 	} verify {
 		let expected: BoundedVec<BlockNumberFor<T>, T::MaxScheduledBlocks> =
-			bounded_vec![now + One::one()];
+			BoundedVec::try_from(vec![now + One::one()]).unwrap();
 		assert_eq!(Queue::<T>::get(), expected);
 	}
 
diff --git a/substrate/frame/scheduler/src/migration.rs b/substrate/frame/scheduler/src/migration.rs
index 3879206d8330..09d915b8d423 100644
--- a/substrate/frame/scheduler/src/migration.rs
+++ b/substrate/frame/scheduler/src/migration.rs
@@ -615,8 +615,8 @@ pub mod v5 {
 pub mod test {
 	use super::*;
 	use crate::{migration::v5::IncompleteSince, mock::*};
+	use alloc::vec;
 	use frame_support::testing_prelude::*;
-	use scale_info::prelude::vec;
 
 	#[test]
 	fn migration_v4_to_v5_works() {

From 2ea271adf830d96570fc37f6e95a4412a602681f Mon Sep 17 00:00:00 2001
From: gupnik <17176722+gupnik@users.noreply.github.com>
Date: Fri, 15 Nov 2024 16:08:09 +0530
Subject: [PATCH 12/16] Minor fix

---
 substrate/frame/scheduler/src/migration.rs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/substrate/frame/scheduler/src/migration.rs b/substrate/frame/scheduler/src/migration.rs
index 09d915b8d423..ae1d351874ac 100644
--- a/substrate/frame/scheduler/src/migration.rs
+++ b/substrate/frame/scheduler/src/migration.rs
@@ -563,6 +563,7 @@ mod test {
 
 pub mod v5 {
 	use super::*;
+	use alloc::vec;
 	use frame_support::{
 		migrations::VersionedMigration, pallet_prelude::*, traits::UncheckedOnRuntimeUpgrade,
 	};

From 9a73c23e1521e8150011ce7309d9f63058912758 Mon Sep 17 00:00:00 2001
From: gupnik <17176722+gupnik@users.noreply.github.com>
Date: Fri, 15 Nov 2024 16:20:42 +0530
Subject: [PATCH 13/16] Minor fix

---
 .../runtimes/collectives/collectives-westend/src/lib.rs        | 3 ++-
 polkadot/runtime/rococo/src/lib.rs                             | 2 +-
 polkadot/runtime/westend/src/lib.rs                            | 2 +-
 3 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/cumulus/parachains/runtimes/collectives/collectives-westend/src/lib.rs b/cumulus/parachains/runtimes/collectives/collectives-westend/src/lib.rs
index 62927807afb8..f19eb73c367e 100644
--- a/cumulus/parachains/runtimes/collectives/collectives-westend/src/lib.rs
+++ b/cumulus/parachains/runtimes/collectives/collectives-westend/src/lib.rs
@@ -605,13 +605,14 @@ parameter_types! {
 parameter_types! {
 	pub const MaxScheduledPerBlock: u32 = 50;
 	pub const MaxScheduledBlocks: u32 = 50;
+	pub const MaxStaleTaskAge: u32 = 10;
 }
 
 #[cfg(feature = "runtime-benchmarks")]
 parameter_types! {
 	pub const MaxScheduledPerBlock: u32 = 200;
 	pub const MaxScheduledBlocks: u32 = 200;
-	pub const MaxStaleTaskAge: u64 = 10;
+	pub const MaxStaleTaskAge: u32 = 40;
 }
 
 impl pallet_scheduler::Config for Runtime {
diff --git a/polkadot/runtime/rococo/src/lib.rs b/polkadot/runtime/rococo/src/lib.rs
index 840408979c5f..0cbe0ab8bf16 100644
--- a/polkadot/runtime/rococo/src/lib.rs
+++ b/polkadot/runtime/rococo/src/lib.rs
@@ -232,7 +232,7 @@ parameter_types! {
 		BlockWeights::get().max_block;
 	pub const MaxScheduledPerBlock: u32 = 50;
 	pub const MaxScheduledBlocks: u32 = 50;
-	pub const MaxStaleTaskAge: u64 = 10;
+	pub const MaxStaleTaskAge: u32 = 10;
 	pub const NoPreimagePostponement: Option<u32> = Some(10);
 }
 
diff --git a/polkadot/runtime/westend/src/lib.rs b/polkadot/runtime/westend/src/lib.rs
index c05ce1228d41..74b58fa71d32 100644
--- a/polkadot/runtime/westend/src/lib.rs
+++ b/polkadot/runtime/westend/src/lib.rs
@@ -233,7 +233,7 @@ parameter_types! {
 		BlockWeights::get().max_block;
 	pub const MaxScheduledPerBlock: u32 = 50;
 	pub const MaxScheduledBlocks: u32 = 50;
-	pub const MaxStaleTaskAge: u64 = 10;
+	pub const MaxStaleTaskAge: u32 = 10;
 	pub const NoPreimagePostponement: Option<u32> = Some(10);
 }
 

From ece20279c65b1336abf71afb68fb310ef4fd54db Mon Sep 17 00:00:00 2001
From: gupnik <17176722+gupnik@users.noreply.github.com>
Date: Fri, 15 Nov 2024 16:31:38 +0530
Subject: [PATCH 14/16] Removes unused import

---
 substrate/frame/scheduler/src/benchmarking.rs | 1 -
 1 file changed, 1 deletion(-)

diff --git a/substrate/frame/scheduler/src/benchmarking.rs b/substrate/frame/scheduler/src/benchmarking.rs
index 8cb622f8e59d..e4578fb45a60 100644
--- a/substrate/frame/scheduler/src/benchmarking.rs
+++ b/substrate/frame/scheduler/src/benchmarking.rs
@@ -27,7 +27,6 @@ use frame_support::{
 	weights::WeightMeter,
 };
 use frame_system::RawOrigin;
-use sp_runtime::bounded_vec;
 
 use crate::Pallet as Scheduler;
 use frame_system::{Call as SystemCall, EventRecord};

From da116a70b2250f8113b40d7c724147fec24586e5 Mon Sep 17 00:00:00 2001
From: gupnik <17176722+gupnik@users.noreply.github.com>
Date: Fri, 15 Nov 2024 16:45:19 +0530
Subject: [PATCH 15/16] Minor

---
 substrate/bin/node/runtime/src/lib.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/substrate/bin/node/runtime/src/lib.rs b/substrate/bin/node/runtime/src/lib.rs
index d49d91563762..311e6fa4deef 100644
--- a/substrate/bin/node/runtime/src/lib.rs
+++ b/substrate/bin/node/runtime/src/lib.rs
@@ -504,7 +504,7 @@ impl pallet_scheduler::Config for Runtime {
 	type MaxScheduledBlocks = ConstU32<512>;
 	#[cfg(not(feature = "runtime-benchmarks"))]
 	type MaxScheduledBlocks = ConstU32<50>;
-	type MaxStaleTaskAge = ConstU64<10>;
+	type MaxStaleTaskAge = ConstU32<10>;
 }
 
 impl pallet_glutton::Config for Runtime {

From b1b414a4d5d646059d0495585020d3711adee291 Mon Sep 17 00:00:00 2001
From: gupnik <17176722+gupnik@users.noreply.github.com>
Date: Fri, 15 Nov 2024 17:16:01 +0530
Subject: [PATCH 16/16] Minor

---
 substrate/frame/scheduler/src/migration.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/substrate/frame/scheduler/src/migration.rs b/substrate/frame/scheduler/src/migration.rs
index ae1d351874ac..870ec17e764e 100644
--- a/substrate/frame/scheduler/src/migration.rs
+++ b/substrate/frame/scheduler/src/migration.rs
@@ -613,7 +613,7 @@ pub mod v5 {
 }
 
 #[cfg(test)]
-pub mod test {
+pub mod test_v5 {
 	use super::*;
 	use crate::{migration::v5::IncompleteSince, mock::*};
 	use alloc::vec;