Remove AssignmentProviderConfig and use parameters from HostConfiguration instead (#3181)

This PR removes `AssignmentProviderConfig` and uses the corresponding
ondemand parameters from `HostConfiguration` instead. Additionally
`scheduling_lookahead` and all coretime/ondemand related parameters are
extracted in a separate struct - `SchedulerParams`.

The most relevant commit from the PR is [this
one](https://github.com/paritytech/polkadot-sdk/pull/3181/commits/830bc0f5e858944474171bbe33382ad96040b535).

Fixes https://github.com/paritytech/polkadot-sdk/issues/2268

---------

Co-authored-by: command-bot <>

polkadot/primitives/src/vstaging/mod.rs

@@ -23,6 +23,7 @@ use sp_std::prelude::*;
 use parity_scale_codec::{Decode, Encode};
 use primitives::RuntimeDebug;
 use scale_info::TypeInfo;
+use sp_arithmetic::Perbill;
 
 /// Approval voting configuration parameters
 #[derive(
@@ -50,6 +51,81 @@ impl Default for ApprovalVotingParams {
 	}
 }
 
+/// Scheduler configuration parameters. All coretime/ondemand parameters are here.
+#[derive(
+	RuntimeDebug,
+	Copy,
+	Clone,
+	PartialEq,
+	Encode,
+	Decode,
+	TypeInfo,
+	serde::Serialize,
+	serde::Deserialize,
+)]
+pub struct SchedulerParams<BlockNumber> {
+	/// How often parachain groups should be rotated across parachains.
+	///
+	/// Must be non-zero.
+	pub group_rotation_frequency: BlockNumber,
+	/// Availability timeout for a block on a core, measured in blocks.
+	///
+	/// This is the maximum amount of blocks after a core became occupied that validators have time
+	/// to make the block available.
+	///
+	/// This value only has effect on group rotations. If backers backed something at the end of
+	/// their rotation, the occupied core affects the backing group that comes afterwards. We limit
+	/// the effect one backing group can have on the next to `paras_availability_period` blocks.
+	///
+	/// Within a group rotation there is no timeout as backers are only affecting themselves.
+	///
+	/// Must be at least 1. With a value of 1, the previous group will not be able to negatively
+	/// affect the following group at the expense of a tight availability timeline at group
+	/// rotation boundaries.
+	pub paras_availability_period: BlockNumber,
+	/// The maximum number of validators to have per core.
+	///
+	/// `None` means no maximum.
+	pub max_validators_per_core: Option<u32>,
+	/// The amount of blocks ahead to schedule paras.
+	pub lookahead: u32,
+	/// How many cores are managed by the coretime chain.
+	pub num_cores: u32,
+	/// The max number of times a claim can time out in availability.
+	pub max_availability_timeouts: u32,
+	/// The maximum queue size of the pay as you go module.
+	pub on_demand_queue_max_size: u32,
+	/// The target utilization of the spot price queue in percentages.
+	pub on_demand_target_queue_utilization: Perbill,
+	/// How quickly the fee rises in reaction to increased utilization.
+	/// The lower the number the slower the increase.
+	pub on_demand_fee_variability: Perbill,
+	/// The minimum amount needed to claim a slot in the spot pricing queue.
+	pub on_demand_base_fee: Balance,
+	/// The number of blocks a claim stays in the scheduler's claimqueue before getting cleared.
+	/// This number should go reasonably higher than the number of blocks in the async backing
+	/// lookahead.
+	pub ttl: BlockNumber,
+}
+
+impl<BlockNumber: Default + From<u32>> Default for SchedulerParams<BlockNumber> {
+	fn default() -> Self {
+		Self {
+			group_rotation_frequency: 1u32.into(),
+			paras_availability_period: 1u32.into(),
+			max_validators_per_core: Default::default(),
+			lookahead: 1,
+			num_cores: Default::default(),
+			max_availability_timeouts: Default::default(),
+			on_demand_queue_max_size: ON_DEMAND_DEFAULT_QUEUE_MAX_SIZE,
+			on_demand_target_queue_utilization: Perbill::from_percent(25),
+			on_demand_fee_variability: Perbill::from_percent(3),
+			on_demand_base_fee: 10_000_000u128,
+			ttl: 5u32.into(),
+		}
+	}
+}
+
 use bitvec::vec::BitVec;
 
 /// Bit indices in the `HostConfiguration.node_features` that correspond to different node features.