Struct MemPool

pub struct MemPool<Block: BlockT, Client> { /* private fields */ }

Thread-safe Bitcoin mempool.

Uses RwLock for interior mutability with the following lock hierarchy:

1. MemPool::inner (RwLock)
2. MemPool::coins_cache (RwLock)
3. Runtime state backend (internal to client)

CRITICAL: Always acquire locks in this order to avoid deadlocks.

Implementations

impl<Block, Client> MemPool<Block, Client>

where Block: BlockT, Client: ProvideRuntimeApi<Block> + HeaderBackend<Block> + AuxStore + Send + Sync, Client::Api: SubcoinApi<Block>,

pub fn new(client: Arc<Client>) -> Self

Create a new mempool with default options.

pub fn with_options(client: Arc<Client>, options: MemPoolOptions) -> Self

Create a new mempool with custom options.

pub fn accept_single_transaction( &self, tx: Transaction, ) -> Result<(), MempoolError>

Accept a single transaction into the mempool.

CRITICAL: Holds write lock for entire ATMP flow to prevent TOCTOU races.

pub fn size(&self) -> usize

Get number of transactions in mempool.

pub fn total_size(&self) -> u64

Get total size of all transactions in bytes.

pub fn trim_to_size(&self, max_size: u64)

Trim mempool to maximum size.

pub fn expire(&self, max_age_seconds: i64)

Expire old transactions.

pub fn options(&self) -> &MemPoolOptions

Get mempool options.

pub fn remove_for_block( &self, confirmed_txs: &[Transaction], new_best_block: Block::Hash, ) -> Result<(), MempoolError>

Remove transactions confirmed in a block.

This is called after a new block is connected to remove transactions that were included in the block, as well as any conflicts.

Lock hierarchy: Acquires inner write lock, then coins_cache write lock.

pub fn remove_conflicts(&self, txs: &[Transaction]) -> Result<(), MempoolError>

Remove conflicts for a set of transactions.

This is used when accepting a package of transactions to remove any existing mempool transactions that conflict with the package.

pub fn remove_for_reorg( &self, new_tip_height: u32, new_best_block: Block::Hash, ) -> Result<(), MempoolError>

Remove transactions that are no longer valid after a reorg.

Prunes transactions based on:

• Height-based timelocks (nLockTime)
• Coinbase maturity violations
• Sequence-based timelocks (BIP68)
• Max input block no longer on active chain

Lock hierarchy: Acquires inner write lock, then coins_cache write lock.

pub fn accept_package( &self, transactions: Vec<Transaction>, ) -> Result<PackageValidationResult, MempoolError>

Accept a package of related transactions (CPFP support).

All transactions are validated as a unit. If any fails, none are accepted.

pub fn contains_txid(&self, txid: &Txid) -> bool

Check if transaction exists in mempool.

pub fn get_transaction(&self, txid: &Txid) -> Option<Arc<Transaction>>

Get transaction from mempool if present.

pub fn pending_broadcast_txs(&self) -> Vec<(Txid, u64)>

Get transactions pending broadcast with their fee rates.

pub fn mark_broadcast_txs(&self, txids: &[Txid])

Mark transactions as broadcast.

pub fn iter_txids_by_priority(&self) -> Vec<(Txid, u64)>

Iterate over all transaction IDs with their fee rates, sorted by mining priority.

Trait Implementations

impl<Block, Client> TxPool for MemPool<Block, Client>

where Block: BlockT + 'static, Client: ProvideRuntimeApi<Block> + HeaderBackend<Block> + AuxStore + Send + Sync + 'static, Client::Api: SubcoinApi<Block>,

fn validate_transaction(&self, tx: Transaction) -> TxValidationResult

Validate and potentially accept a transaction into the mempool.

fn contains(&self, txid: &Txid) -> bool

Check if transaction is already in mempool.

fn get(&self, txid: &Txid) -> Option<Arc<Transaction>>

Get transaction from mempool if present.

fn pending_broadcast(&self) -> Vec<(Txid, u64)>

Get transactions pending broadcast to peers. Returns (txid, fee_rate) pairs.

fn mark_broadcast(&self, txids: &[Txid])

Mark transactions as broadcast to peers.

fn iter_txids(&self) -> Box<dyn Iterator<Item = (Txid, u64)> + Send>

Iterate over all transaction IDs with their fee rates. Returns (txid, fee_rate) pairs sorted by mining priority.

fn info(&self) -> TxPoolInfo

Get mempool statistics.