Increase transaction account lock limit from 64 to 128

programs/bpf/tests/programs.rs

@@ -1288,7 +1288,7 @@ fn test_program_bpf_invoke_sanity() {
                 format!("Program log: invoke {program_lang} program"),
                 "Program log: Test max account infos exceeded".into(),
                 "skip".into(), // don't compare compute consumption logs
-                "Program failed to complete: Invoked an instruction with too many account info's (65 > 64)".into(),
+                "Program failed to complete: Invoked an instruction with too many account info's (129 > 128)".into(),
                 format!("Program {invoke_program_id} failed: Program failed to complete"),
             ]),
         );

programs/bpf_loader/src/syscalls/cpi.rs

@@ -799,8 +799,16 @@ fn check_account_infos(
         .feature_set
         .is_active(&feature_set::loosen_cpi_size_restriction::id())
     {
+        let max_cpi_account_infos = if invoke_context
+            .feature_set
+            .is_active(&feature_set::increase_tx_account_lock_limit::id())
+        {
+            MAX_CPI_ACCOUNT_INFOS
+        } else {
+            64
+        };
         let num_account_infos = num_account_infos as u64;
-        let max_account_infos = MAX_CPI_ACCOUNT_INFOS as u64;
+        let max_account_infos = max_cpi_account_infos as u64;
         if num_account_infos > max_account_infos {
             return Err(SyscallError::MaxInstructionAccountInfosExceeded {
                 num_account_infos,

runtime/src/bank.rs

@@ -3913,8 +3913,13 @@ impl Bank {
             self.runtime_config.transaction_account_lock_limit
         {
             transaction_account_lock_limit
-        } else {
+        } else if self
+            .feature_set
+            .is_active(&feature_set::increase_tx_account_lock_limit::id())
+        {
             MAX_TX_ACCOUNT_LOCKS
+        } else {
+            64
         }
     }
 
@@ -8127,7 +8132,6 @@ pub(crate) mod tests {
             },
             system_program,
             timing::duration_as_s,
-            transaction::MAX_TX_ACCOUNT_LOCKS,
             transaction_context::IndexOfAccount,
         },
         solana_vote_program::{
@@ -14353,7 +14357,8 @@ pub(crate) mod tests {
             bank.last_blockhash(),
         );
 
-        while tx.message.account_keys.len() <= MAX_TX_ACCOUNT_LOCKS {
+        let transaction_account_lock_limit = bank.get_transaction_account_lock_limit();
+        while tx.message.account_keys.len() <= transaction_account_lock_limit {
             tx.message.account_keys.push(solana_sdk::pubkey::new_rand());
         }
 

sdk/bpf/c/inc/sol/cpi.h

@@ -28,10 +28,10 @@ static const uint8_t MAX_CPI_INSTRUCTION_ACCOUNTS = 255;
 /**
  * Maximum number of account info structs that can be used in a single CPI
  * invocation. A limit on account info structs is effectively the same as
- * limiting the number of unique accounts. 64 was chosen to match the max
+ * limiting the number of unique accounts. 128 was chosen to match the max
  * number of locked accounts per transaction (MAX_TX_ACCOUNT_LOCKS).
  */
-static const uint8_t MAX_CPI_ACCOUNT_INFOS = 64;
+static const uint16_t MAX_CPI_ACCOUNT_INFOS = 128;
 
 /**
  * Account Meta

sdk/bpf/c/inc/sol/inc/cpi.inc

@@ -28,10 +28,10 @@ static const uint8_t MAX_CPI_INSTRUCTION_ACCOUNTS = 255;
 /**
  * Maximum number of account info structs that can be used in a single CPI
  * invocation. A limit on account info structs is effectively the same as
- * limiting the number of unique accounts. 64 was chosen to match the max
+ * limiting the number of unique accounts. 128 was chosen to match the max
  * number of locked accounts per transaction (MAX_TX_ACCOUNT_LOCKS).
  */
-static const uint8_t MAX_CPI_ACCOUNT_INFOS = 64;
+static const uint16_t MAX_CPI_ACCOUNT_INFOS = 128;
 
 /**
  * Account Meta

sdk/program/src/syscalls/mod.rs

@@ -16,6 +16,6 @@ pub const MAX_CPI_INSTRUCTION_ACCOUNTS: u8 = u8::MAX;
 
 /// Maximum number of account info structs that can be used in a single CPI
 /// invocation. A limit on account info structs is effectively the same as
-/// limiting the number of unique accounts. 64 was chosen to match the max
+/// limiting the number of unique accounts. 128 was chosen to match the max
 /// number of locked accounts per transaction (MAX_TX_ACCOUNT_LOCKS).
-pub const MAX_CPI_ACCOUNT_INFOS: usize = 64;
+pub const MAX_CPI_ACCOUNT_INFOS: usize = 128;

sdk/src/feature_set.rs

@@ -522,6 +522,10 @@ pub mod remove_deprecated_request_unit_ix {
     solana_sdk::declare_id!("EfhYd3SafzGT472tYQDUc4dPd2xdEfKs5fwkowUgVt4W");
 }
 
+pub mod increase_tx_account_lock_limit {
+    solana_sdk::declare_id!("9LZdXeKGeBV6hRLdxS1rHbHoEUsKqesCC2ZAPTPKJAbK");
+}
+
 lazy_static! {
     /// Map of feature identifiers to user-visible description
     pub static ref FEATURE_NAMES: HashMap<Pubkey, &'static str> = [
@@ -647,6 +651,7 @@ lazy_static! {
         (cap_accounts_data_allocations_per_transaction::id(), "cap accounts data allocations per transaction #27375"),
         (epoch_accounts_hash::id(), "enable epoch accounts hash calculation #27539"),
         (remove_deprecated_request_unit_ix::id(), "remove support for RequestUnitsDeprecated instruction #27500"),
+        (increase_tx_account_lock_limit::id(), "increase tx account lock limit to 128 #27241"),
         /*************** ADD NEW FEATURES HERE ***************/
     ]
     .iter()

sdk/src/transaction/sanitized.rs

@@ -21,9 +21,9 @@ use {
 };
 
 /// Maximum number of accounts that a transaction may lock.
-/// 64 was chosen because it is roughly twice the previous
-/// number of account keys that could fit in a legacy tx.
-pub const MAX_TX_ACCOUNT_LOCKS: usize = 64;
+/// 128 was chosen because it is the minimum number of accounts
+/// needed for the Neon EVM implementation.
+pub const MAX_TX_ACCOUNT_LOCKS: usize = 128;
 
 /// Sanitized transaction and the hash of its message
 #[derive(Debug, Clone)]