chore: refactor critical nonce into get_number_of_available_sol_nonce…

…_accounts

state-chain/chains/src/sol.rs

@@ -53,12 +53,14 @@ pub const CCM_BYTES_PER_ACCOUNT: usize = 33usize;
 pub const MAX_CCM_BYTES_SOL: usize = MAX_TRANSACTION_LENGTH - 527usize; // 705 bytes left
 pub const MAX_CCM_BYTES_USDC: usize = MAX_TRANSACTION_LENGTH - 740usize; // 492 bytes left
 
+// Nonce management values
+pub const NONCE_NUMBER_CRITICAL_NONCES: usize = 1;
+pub const NONCE_AVAILABILITY_THRESHOLD_FOR_INITIATING_TRANSFER: usize = 1;
+
 // Values used when closing vault swap accounts.
 pub const MAX_BATCH_SIZE_OF_VAULT_SWAP_ACCOUNT_CLOSURES: usize = 5;
 pub const MAX_WAIT_BLOCKS_FOR_SWAP_ACCOUNT_CLOSURE_APICALLS: u32 = 14400;
-pub const NONCE_AVAILABILITY_THRESHOLD_FOR_INITIATING_SWAP_ACCOUNT_CLOSURES: usize = 4;
-// Leaving always one nonce for a potential rotation.
-pub const NONCE_AVAILABILITY_THRESHOLD_FOR_INITIATING_FETCH: usize = 1;
+pub const NONCE_AVAILABILITY_THRESHOLD_FOR_INITIATING_SWAP_ACCOUNT_CLOSURES: usize = 3;
 
 // Use serialized transaction
 #[derive(Encode, Decode, TypeInfo, Clone, RuntimeDebug, Default, PartialEq, Eq)]

state-chain/pallets/cf-elections/src/electoral_systems/solana_vault_swap_accounts.rs

@@ -21,7 +21,6 @@ use crate::{
 use cf_chains::sol::{
 	MAX_BATCH_SIZE_OF_VAULT_SWAP_ACCOUNT_CLOSURES,
 	MAX_WAIT_BLOCKS_FOR_SWAP_ACCOUNT_CLOSURE_APICALLS,
-	NONCE_AVAILABILITY_THRESHOLD_FOR_INITIATING_FETCH,
 	NONCE_AVAILABILITY_THRESHOLD_FOR_INITIATING_SWAP_ACCOUNT_CLOSURES,
 };
 
@@ -37,7 +36,7 @@ use sp_std::vec::Vec;
 pub trait SolanaVaultSwapAccountsHook<Account, SwapDetails, E> {
 	fn maybe_fetch_and_close_accounts(accounts: Vec<Account>) -> Result<(), E>;
 	fn initiate_vault_swap(swap_details: SwapDetails);
-	fn get_number_of_available_sol_nonce_accounts() -> usize;
+	fn get_number_of_available_sol_nonce_accounts(critical: bool) -> usize;
 }
 
 pub trait FromSolOrNot {
@@ -192,13 +191,11 @@ impl<
 					ElectoralAccess::new_election(Default::default(), known_accounts, ())?;
 			}
 
-			let no_of_available_nonces = Hook::get_number_of_available_sol_nonce_accounts();
+			let no_of_available_nonces = Hook::get_number_of_available_sol_nonce_accounts(false);
 			let mut known_accounts = election_access.properties()?;
 			// We need to have at least two nonces available since we need to have one nonce
 			// reserved for solana rotation
-			if no_of_available_nonces > NONCE_AVAILABILITY_THRESHOLD_FOR_INITIATING_FETCH &&
-				!known_accounts.witnessed_open_accounts.is_empty()
-			{
+			if no_of_available_nonces > 0 && !known_accounts.witnessed_open_accounts.is_empty() {
 				known_accounts.witnessed_open_accounts.sort_by_key(|a| Reverse(a.1));
 				// Native Vault swaps assets need to be fetched from the Swap Endpoint's Vault.
 				// Therefore initiating a fetch is a high priority action after a native Vault

state-chain/pallets/cf-environment/src/lib.rs

@@ -14,7 +14,7 @@ use cf_chains::{
 	eth::Address as EvmAddress,
 	sol::{
 		api::{DurableNonceAndAccount, SolanaApi, SolanaEnvironment, SolanaGovCall},
-		SolAddress, SolApiEnvironment, SolHash, Solana,
+		SolAddress, SolApiEnvironment, SolHash, Solana, NONCE_NUMBER_CRITICAL_NONCES,
 	},
 	Chain,
 };
@@ -779,8 +779,15 @@ impl<T: Config> Pallet<T> {
 		nonce_accounts
 	}
 
-	pub fn get_number_of_available_sol_nonce_accounts() -> usize {
-		SolanaAvailableNonceAccounts::<T>::decode_len().unwrap_or(0)
+	// Get the number of available nonce accounts. We want to leave a number of available nonces
+	// at all time for critical operations such as vault rotations or governance actions.
+	pub fn get_number_of_available_sol_nonce_accounts(critical: bool) -> usize {
+		let number_nonces = SolanaAvailableNonceAccounts::<T>::decode_len().unwrap_or(0);
+		if !critical {
+			number_nonces.saturating_sub(NONCE_NUMBER_CRITICAL_NONCES)
+		} else {
+			number_nonces
+		}
 	}
 
 	pub fn update_sol_nonce(nonce_account: SolAddress, durable_nonce: SolHash) {

state-chain/runtime/src/chainflip.rs

@@ -55,7 +55,7 @@ use cf_chains::{
 			SolanaEnvironment,
 		},
 		SolAddress, SolAmount, SolApiEnvironment, SolanaCrypto, SolanaTransactionData,
-		NONCE_AVAILABILITY_THRESHOLD_FOR_INITIATING_FETCH,
+		NONCE_AVAILABILITY_THRESHOLD_FOR_INITIATING_TRANSFER,
 	},
 	AnyChain, ApiCall, Arbitrum, CcmChannelMetadata, CcmDepositMetadata, Chain, ChainCrypto,
 	ChainEnvironment, ChainState, ChannelRefundParametersDecoded, ForeignChain,
@@ -946,9 +946,8 @@ impl FetchesTransfersLimitProvider for SolanaLimit {
 		// we need to leave one nonce for the fetch tx and one nonce reserved for rotation tx since
 		// rotation tx can fail to build if all nonce accounts are occupied
 		Some(
-			Environment::get_number_of_available_sol_nonce_accounts().saturating_sub(
-				NONCE_AVAILABILITY_THRESHOLD_FOR_INITIATING_FETCH.saturating_add(1),
-			),
+			Environment::get_number_of_available_sol_nonce_accounts(false)
+				.saturating_sub(NONCE_AVAILABILITY_THRESHOLD_FOR_INITIATING_TRANSFER),
 		)
 	}
 
@@ -961,15 +960,11 @@ impl FetchesTransfersLimitProvider for SolanaLimit {
 	fn maybe_fetches_limit() -> Option<usize> {
 		// only fetch if we have more than once nonce account available since one nonce is
 		// reserved for rotations. See above
-		Some(
-			if Environment::get_number_of_available_sol_nonce_accounts() >
-				NONCE_AVAILABILITY_THRESHOLD_FOR_INITIATING_FETCH
-			{
-				cf_chains::sol::MAX_SOL_FETCHES_PER_TX
-			} else {
-				0
-			},
-		)
+		Some(if Environment::get_number_of_available_sol_nonce_accounts(false) > 0 {
+			cf_chains::sol::MAX_SOL_FETCHES_PER_TX
+		} else {
+			0
+		})
 	}
 }
 

state-chain/runtime/src/chainflip/solana_elections.rs

@@ -610,8 +610,8 @@ impl
 			})
 	}
 
-	fn get_number_of_available_sol_nonce_accounts() -> usize {
-		Environment::get_number_of_available_sol_nonce_accounts()
+	fn get_number_of_available_sol_nonce_accounts(critical: bool) -> usize {
+		Environment::get_number_of_available_sol_nonce_accounts(critical)
 	}
 }