CPE

// Sealevel Account Locking Model

struct Transaction {

accounts: Vec<AccountMeta>,

instructions: Vec<Instruction>,

}

// AccountMeta declares access pattern

struct AccountMeta {

pubkey: Pubkey,

is_signer: bool,

is_writable: bool,

}

// Lock rules:

// - Writable accounts: exclusive lock (one tx at a time)

// - Read-only accounts: shared lock (many txs simultaneously)

// - No overlap in write sets = parallel execution eligible

// Sealevel Thread Model (simplified)

struct SealevelScheduler {

threads: Vec<WorkerThread>,

lock_table: HashMap<Pubkey, LockState>,

}

fn schedule(txs: Vec<Transaction>) -> Vec<ThreadBatch> {

// 1. Build dependency graph from account declarations

let graph = build_dependency_graph(&txs);

// 2. Find connected components (groups of dependent txs)

let components = graph.connected_components();

// 3. Assign each independent component to a thread

components.iter().enumerate().map(|(i, comp)| {

ThreadBatch {

thread_id: i % self.threads.len(),

transactions: comp.clone(),

}

}).collect()

}

// Key insight: CPE transactions form their own connected

// component with zero edges (no dependencies between them)

// This guarantees they are assigned to SEPARATE threads

// Contention Analysis Algorithm

fn analyze_contention(bundle: &CpeBundle) -> ContentionReport {

let mut contention_map: HashMap<Pubkey, Vec<usize>> = HashMap::new();

// Map each writable account to the txs that touch it

for (i, tx) in bundle.transactions.iter().enumerate() {

for acc in tx.writable_accounts() {

contention_map.entry(acc).or_default().push(i);

}

}

// Identify hot accounts (touched by more than 1 tx)

let hot_accounts: Vec<_> = contention_map

.iter()

.filter(|(_, txs)| txs.len() > 1)

.collect();

ContentionReport {

is_parallel_eligible: hot_accounts.is_empty(),

hot_accounts,

contention_score: compute_score(&contention_map),

}

}

// CPE Validation Algorithm

fn validate_cpe_bundle(bundle: &CpeBundle) -> Result<CpeProof> {

let txs = &bundle.transactions;

// Step 1: Extract write account sets

let write_sets: Vec<HashSet<Pubkey>> = txs

.iter()

.map(|tx| extract_write_accounts(tx))

.collect();

// Step 2: Pairwise overlap check

for i in 0..write_sets.len() {

for j in (i+1)..write_sets.len() {

let overlap = write_sets[i].intersection(&write_sets[j]);

if overlap.count() > 0 {

return Err(CpeError::OverlappingAccounts);

}

}

}

// Step 3: Generate parallel execution proof

Ok(generate_cpe_proof(bundle, &write_sets))

}

// CPE Proof Structure

struct CpeProof {

// Bundle metadata

bundle_id: Hash,

transaction_count: u8,

slot: u64,

// Account analysis

write_sets: Vec<Vec<Pubkey>>,

read_sets: Vec<Vec<Pubkey>>,

overlap_matrix: [[bool; MAX_TXS]; MAX_TXS],

// Execution proof

parallel_eligible: bool,

execution_hash: Hash,

timestamp: i64,

// $MONO burn record

mono_burned: u64,

burn_signature: Signature,

}

// CPE Proof Verification Algorithm

fn verify_cpe_proof(proof: &CpeProof, rpc: &RpcClient) -> bool {

// Step 1: Fetch transactions from the claimed slot

let slot_txs = rpc.get_block(proof.slot)?.transactions;

// Step 2: Confirm all bundle txs exist in the slot

let bundle_sigs = proof.transaction_signatures();

if !bundle_sigs.iter().all(|s| slot_txs.contains(s)) {

return false; // Not all txs in the same slot

}

// Step 3: Re-extract write sets from on-chain data

let actual_write_sets = bundle_sigs.iter()

.map(|sig| extract_write_accounts_from_chain(rpc, sig))

.collect::<Vec<_>>();

// Step 4: Verify zero overlap

for i in 0..actual_write_sets.len() {

for j in (i+1)..actual_write_sets.len() {

if !actual_write_sets[i].is_disjoint(&actual_write_sets[j]) {

return false; // Write overlap detected

}

}

}

// Step 5: Verify execution hash

let expected_hash = compute_execution_hash(

&proof.bundle_id, proof.slot, &actual_write_sets

);

expected_hash == proof.execution_hash

}

// Account Set Analysis

fn extract_write_accounts(tx: &Transaction) -> HashSet<Pubkey> {

let mut accounts = HashSet::new();

for meta in &tx.message.account_keys {

if meta.is_writable {

accounts.insert(meta.pubkey);

}

}

// Include CPI-derived accounts

for ix in &tx.message.instructions {

let cpi_accounts = resolve_cpi_accounts(ix);

accounts.extend(cpi_accounts);

}

accounts

}

// Complexity: O(n^2 * m) where n = tx count, m = avg accounts per tx

// For typical CPE bundles (2-8 txs), this is sub-millisecond

// Integration Architecture

Layer 4: Application -- DeFi protocols, traders, searchers

Layer 3: MonoGirl CPE -- Validation, proof generation, $MONO burn

Layer 2: RPC / Relay -- Transaction submission to validators

Layer 1: Sealevel Runtime -- Account locking, thread scheduling

Layer 0: Solana Consensus -- PoH, Tower BFT, slot production