CTxMemPool stores valid-according-to-the-current-best-chain transactions that may be included in the next block. More...

#include <txmempool.h>

Collaboration diagram for CTxMemPool:

[legend]

Public Types
typedef boost::multi_index_container< CTxMemPoolEntry, boost::multi_index::indexed_by< boost::multi_index::hashed_unique< mempoolentry_txid, SaltedTxidHasher >, boost::multi_index::hashed_unique< boost::multi_index::tag< index_by_wtxid >, mempoolentry_wtxid, SaltedTxidHasher >, boost::multi_index::ordered_non_unique< boost::multi_index::tag< descendant_score >, boost::multi_index::identity< CTxMemPoolEntry >, CompareTxMemPoolEntryByDescendantScore >, boost::multi_index::ordered_non_unique< boost::multi_index::tag< entry_time >, boost::multi_index::identity< CTxMemPoolEntry >, CompareTxMemPoolEntryByEntryTime >, boost::multi_index::ordered_non_unique< boost::multi_index::tag< ancestor_score >, boost::multi_index::identity< CTxMemPoolEntry >, CompareTxMemPoolEntryByAncestorFee > > >	indexed_transaction_set

using	txiter = indexed_transaction_set::nth_index< 0 >::type::const_iterator

typedef std::set< txiter, CompareIteratorByHash >	setEntries

Public Member Functions
indexed_transaction_set mapTx	GUARDED_BY (cs)

std::vector< std::pair< uint256, txiter > > vTxHashes	GUARDED_BY (cs)
	All tx witness hashes/entries in mapTx, in random order. More...

uint64_t	CalculateDescendantMaximum (txiter entry) const EXCLUSIVE_LOCKS_REQUIRED(cs)

indirectmap< COutPoint, const CTransaction * > mapNextTx	GUARDED_BY (cs)

std::map< uint256, CAmount > mapDeltas	GUARDED_BY (cs)

	CTxMemPool (CBlockPolicyEstimator *estimator=nullptr, int check_ratio=0)
	Create a new CTxMemPool. More...

void	addUnchecked (const CTxMemPoolEntry &entry, setEntries &setAncestors, bool validFeeEstimate=true) EXCLUSIVE_LOCKS_REQUIRED(cs

void	removeRecursive (const CTransaction &tx, MemPoolRemovalReason reason) EXCLUSIVE_LOCKS_REQUIRED(cs)

void	removeForReorg (CChain &chain, std::function< bool(txiter)> filter_final_and_mature) EXCLUSIVE_LOCKS_REQUIRED(cs
	After reorg, filter the entries that would no longer be valid in the next block, and update the entries' cached LockPoints if needed. More...

void	removeConflicts (const CTransaction &tx) EXCLUSIVE_LOCKS_REQUIRED(cs)

void	removeForBlock (const std::vector< CTransactionRef > &vtx, unsigned int nBlockHeight) EXCLUSIVE_LOCKS_REQUIRED(cs)
	Called when a block is connected. More...

void	clear ()

void	_clear () EXCLUSIVE_LOCKS_REQUIRED(cs)

bool	CompareDepthAndScore (const uint256 &hasha, const uint256 &hashb, bool wtxid=false)

void	queryHashes (std::vector< uint256 > &vtxid) const

bool	isSpent (const COutPoint &outpoint) const

unsigned int	GetTransactionsUpdated () const

void	AddTransactionsUpdated (unsigned int n)

bool	HasNoInputsOf (const CTransaction &tx) const EXCLUSIVE_LOCKS_REQUIRED(cs)
	Check that none of this transactions inputs are in the mempool, and thus the tx is not dependent on other mempool transactions to be included in a block. More...

void	PrioritiseTransaction (const uint256 &hash, const CAmount &nFeeDelta)
	Affect CreateNewBlock prioritisation of transactions. More...

void	ApplyDelta (const uint256 &hash, CAmount &nFeeDelta) const EXCLUSIVE_LOCKS_REQUIRED(cs)

void	ClearPrioritisation (const uint256 &hash) EXCLUSIVE_LOCKS_REQUIRED(cs)

const CTransaction *	GetConflictTx (const COutPoint &prevout) const EXCLUSIVE_LOCKS_REQUIRED(cs)
	Get the transaction in the pool that spends the same prevout. More...

std::optional< txiter >	GetIter (const uint256 &txid) const EXCLUSIVE_LOCKS_REQUIRED(cs)
	Returns an iterator to the given hash, if found. More...

setEntries	GetIterSet (const std::set< uint256 > &hashes) const EXCLUSIVE_LOCKS_REQUIRED(cs)
	Translate a set of hashes into a set of pool iterators to avoid repeated lookups. More...

void	RemoveStaged (setEntries &stage, bool updateDescendants, MemPoolRemovalReason reason) EXCLUSIVE_LOCKS_REQUIRED(cs)
	Remove a set of transactions from the mempool. More...

void	UpdateTransactionsFromBlock (const std::vector< uint256 > &vHashesToUpdate, uint64_t ancestor_size_limit, uint64_t ancestor_count_limit) EXCLUSIVE_LOCKS_REQUIRED(cs
	UpdateTransactionsFromBlock is called when adding transactions from a disconnected block back to the mempool, new mempool entries may have children in the mempool (which is generally not the case when otherwise adding transactions). More...

void cs_main	LOCKS_EXCLUDED (m_epoch)

bool	CalculateMemPoolAncestors (const CTxMemPoolEntry &entry, setEntries &setAncestors, uint64_t limitAncestorCount, uint64_t limitAncestorSize, uint64_t limitDescendantCount, uint64_t limitDescendantSize, std::string &errString, bool fSearchForParents=true) const EXCLUSIVE_LOCKS_REQUIRED(cs)
	Try to calculate all in-mempool ancestors of entry. More...

bool	CheckPackageLimits (const Package &package, uint64_t limitAncestorCount, uint64_t limitAncestorSize, uint64_t limitDescendantCount, uint64_t limitDescendantSize, std::string &errString) const EXCLUSIVE_LOCKS_REQUIRED(cs)
	Calculate all in-mempool ancestors of a set of transactions not already in the mempool and check ancestor and descendant limits. More...

void	CalculateDescendants (txiter it, setEntries &setDescendants) const EXCLUSIVE_LOCKS_REQUIRED(cs)
	Populate setDescendants with all in-mempool descendants of hash. More...

CFeeRate	GetMinFee (size_t sizelimit) const
	The minimum fee to get into the mempool, which may itself not be enough for larger-sized transactions. More...

void	TrimToSize (size_t sizelimit, std::vector< COutPoint > *pvNoSpendsRemaining=nullptr) EXCLUSIVE_LOCKS_REQUIRED(cs)
	Remove transactions from the mempool until its dynamic size is <= sizelimit. More...

int	Expire (std::chrono::seconds time) EXCLUSIVE_LOCKS_REQUIRED(cs)
	Expire all transaction (and their dependencies) in the mempool older than time. More...

void	GetTransactionAncestry (const uint256 &txid, size_t &ancestors, size_t &descendants, size_t ancestorsize=nullptr, CAmount ancestorfees=nullptr) const
	Calculate the ancestor and descendant count for the given transaction. More...

bool	IsLoaded () const

void	SetIsLoaded (bool loaded)
	Sets the current loaded state. More...

unsigned long	size () const

uint64_t	GetTotalTxSize () const EXCLUSIVE_LOCKS_REQUIRED(cs)

CAmount	GetTotalFee () const EXCLUSIVE_LOCKS_REQUIRED(cs)

bool	exists (const GenTxid &gtxid) const

CTransactionRef	get (const uint256 &hash) const

txiter	get_iter_from_wtxid (const uint256 &wtxid) const EXCLUSIVE_LOCKS_REQUIRED(cs)

TxMempoolInfo	info (const GenTxid &gtxid) const

std::vector< TxMempoolInfo >	infoAll () const

size_t	DynamicMemoryUsage () const

void	AddUnbroadcastTx (const uint256 &txid)
	Adds a transaction to the unbroadcast set. More...

void	RemoveUnbroadcastTx (const uint256 &txid, const bool unchecked=false)
	Removes a transaction from the unbroadcast set. More...

std::set< uint256 >	GetUnbroadcastTxs () const
	Returns transactions in unbroadcast set. More...

bool	IsUnbroadcastTx (const uint256 &txid) const EXCLUSIVE_LOCKS_REQUIRED(cs)
	Returns whether a txid is in the unbroadcast set. More...

uint64_t	GetAndIncrementSequence () const EXCLUSIVE_LOCKS_REQUIRED(cs)
	Guards this internal counter for external reporting. More...

uint64_t	GetSequence () const EXCLUSIVE_LOCKS_REQUIRED(cs)

bool	visited (const txiter it) const EXCLUSIVE_LOCKS_REQUIRED(cs
	visited marks a CTxMemPoolEntry as having been traversed during the lifetime of the most recently created Epoch::Guard and returns false if we are the first visitor, true otherwise. More...

bool	visited (std::optional< txiter > it) const EXCLUSIVE_LOCKS_REQUIRED(cs

Public Attributes
RecursiveMutex	cs
	This mutex needs to be locked when accessing `mapTx` or other members that are guarded by it. More...

void check(const CCoinsViewCache &active_coins_tip, int64_t spendheight) const EXCLUSIVE_LOCKS_REQUIRED(void	addUnchecked (const CTxMemPoolEntry &entry, bool validFeeEstimate=true) EXCLUSIVE_LOCKS_REQUIRED(cs
	If sanity-checking is turned on, check makes sure the pool is consistent (does not contain two transactions that spend the same inputs, all inputs are in the mapNextTx array). More...

void check(const CCoinsViewCache &active_coins_tip, int64_t spendheight) const EXCLUSIVE_LOCKS_REQUIRED(void	cs_main

void	cs_main

bool	m_epoch

return !it visited *	it

Static Public Attributes
static const int	ROLLING_FEE_HALFLIFE = 60 * 60 * 12

Protected Member Functions
uint64_t totalTxSize	GUARDED_BY (cs)
	sum of all mempool tx's virtual sizes. Differs from serialized tx size since witness data is discounted. Defined in BIP 141. More...

CAmount m_total_fee	GUARDED_BY (cs)
	sum of all mempool tx's fees (NOT modified fee) More...

uint64_t cachedInnerUsage	GUARDED_BY (cs)
	sum of dynamic memory usage of all the map elements (NOT the maps themselves) More...

int64_t lastRollingFeeUpdate	GUARDED_BY (cs)

bool blockSinceLastRollingFeeBump	GUARDED_BY (cs)

double rollingMinimumFeeRate	GUARDED_BY (cs)
	minimum fee to get into the pool, decreases exponentially More...

Epoch m_epoch	GUARDED_BY (cs)

uint64_t m_sequence_number	GUARDED_BY (cs)

void	trackPackageRemoved (const CFeeRate &rate) EXCLUSIVE_LOCKS_REQUIRED(cs)

bool m_is_loaded	GUARDED_BY (cs)

Protected Attributes
const int	m_check_ratio
	Value n means that 1 times in n we check. More...

std::atomic< unsigned int >	nTransactionsUpdated {0}
	Used by getblocktemplate to trigger CreateNewBlock() invocation. More...

CBlockPolicyEstimator *const	minerPolicyEstimator

Private Types
typedef std::map< txiter, setEntries, CompareIteratorByHash >	cacheMap

Private Member Functions
void	UpdateParent (txiter entry, txiter parent, bool add) EXCLUSIVE_LOCKS_REQUIRED(cs)

void	UpdateChild (txiter entry, txiter child, bool add) EXCLUSIVE_LOCKS_REQUIRED(cs)

std::vector< indexed_transaction_set::const_iterator >	GetSortedDepthAndScore () const EXCLUSIVE_LOCKS_REQUIRED(cs)

std::set< uint256 > m_unbroadcast_txids	GUARDED_BY (cs)
	Track locally submitted transactions to periodically retry initial broadcast. More...

bool	CalculateAncestorsAndCheckLimits (size_t entry_size, size_t entry_count, setEntries &setAncestors, CTxMemPoolEntry::Parents &staged_ancestors, uint64_t limitAncestorCount, uint64_t limitAncestorSize, uint64_t limitDescendantCount, uint64_t limitDescendantSize, std::string &errString) const EXCLUSIVE_LOCKS_REQUIRED(cs)
	Helper function to calculate all in-mempool ancestors of staged_ancestors and apply ancestor and descendant limits (including staged_ancestors thsemselves, entry_size and entry_count). More...

void	UpdateForDescendants (txiter updateIt, cacheMap &cachedDescendants, const std::set< uint256 > &setExclude, std::set< uint256 > &descendants_to_remove, uint64_t ancestor_size_limit, uint64_t ancestor_count_limit) EXCLUSIVE_LOCKS_REQUIRED(cs)
	UpdateForDescendants is used by UpdateTransactionsFromBlock to update the descendants for a single transaction that has been added to the mempool but may have child transactions in the mempool, eg during a chain reorg. More...

void	UpdateAncestorsOf (bool add, txiter hash, setEntries &setAncestors) EXCLUSIVE_LOCKS_REQUIRED(cs)
	Update ancestors of hash to add/remove it as a descendant transaction. More...

void	UpdateEntryForAncestors (txiter it, const setEntries &setAncestors) EXCLUSIVE_LOCKS_REQUIRED(cs)
	Set ancestor state for an entry. More...

void	UpdateForRemoveFromMempool (const setEntries &entriesToRemove, bool updateDescendants) EXCLUSIVE_LOCKS_REQUIRED(cs)
	For each transaction being removed, update ancestors and any direct children. More...

void	UpdateChildrenForRemoval (txiter entry) EXCLUSIVE_LOCKS_REQUIRED(cs)
	Sever link between specified transaction and direct children. More...

void	removeUnchecked (txiter entry, MemPoolRemovalReason reason) EXCLUSIVE_LOCKS_REQUIRED(cs)
	Before calling removeUnchecked for a given transaction, UpdateForRemoveFromMempool must be called on the entire (dependent) set of transactions being removed at the same time. More...

Detailed Description

CTxMemPool stores valid-according-to-the-current-best-chain transactions that may be included in the next block.

Transactions are added when they are seen on the network (or created by the local node), but not all transactions seen are added to the pool. For example, the following new transactions will not be added to the mempool:

a transaction which doesn't meet the minimum fee requirements.
a new transaction that double-spends an input of a transaction already in the pool where the new transaction does not meet the Replace-By-Fee requirements as defined in BIP 125.
a non-standard transaction.

CTxMemPool::mapTx, and CTxMemPoolEntry bookkeeping:

mapTx is a boost::multi_index that sorts the mempool on 5 criteria:

transaction hash (txid)
witness-transaction hash (wtxid)
descendant feerate [we use max(feerate of tx, feerate of tx with all descendants)]
time in mempool
ancestor feerate [we use min(feerate of tx, feerate of tx with all unconfirmed ancestors)]

Note: the term "descendant" refers to in-mempool transactions that depend on this one, while "ancestor" refers to in-mempool transactions that a given transaction depends on.

In order for the feerate sort to remain correct, we must update transactions in the mempool when new descendants arrive. To facilitate this, we track the set of in-mempool direct parents and direct children in mapLinks. Within each CTxMemPoolEntry, we track the size and fees of all descendants.

Usually when a new transaction is added to the mempool, it has no in-mempool children (because any such children would be an orphan). So in addUnchecked(), we:

update a new entry's setMemPoolParents to include all in-mempool parents
update the new entry's direct parents to include the new tx as a child
update all ancestors of the transaction to include the new tx's size/fee

When a transaction is removed from the mempool, we must:

update all in-mempool parents to not track the tx in setMemPoolChildren
update all ancestors to not include the tx's size/fees in descendant state
update all in-mempool children to not include it as a parent

These happen in UpdateForRemoveFromMempool(). (Note that when removing a transaction along with its descendants, we must calculate that set of transactions to be removed before doing the removal, or else the mempool can be in an inconsistent state where it's impossible to walk the ancestors of a transaction.)

In the event of a reorg, the assumption that a newly added tx has no in-mempool children is false. In particular, the mempool is in an inconsistent state while new transactions are being added, because there may be descendant transactions of a tx coming from a disconnected block that are unreachable from just looking at transactions in the mempool (the linking transactions may also be in the disconnected block, waiting to be added). Because of this, there's not much benefit in trying to search for in-mempool children in addUnchecked(). Instead, in the special case of transactions being added from a disconnected block, we require the caller to clean up the state, to account for in-mempool, out-of-block descendants for all the in-block transactions by calling UpdateTransactionsFromBlock(). Note that until this is called, the mempool state is not consistent, and in particular mapLinks may not be correct (and therefore functions like CalculateMemPoolAncestors() and CalculateDescendants() that rely on them to walk the mempool are not generally safe to use).

Computational limits:

Updating all in-mempool ancestors of a newly added transaction can be slow, if no bound exists on how many in-mempool ancestors there may be. CalculateMemPoolAncestors() takes configurable limits that are designed to prevent these calculations from being too CPU intensive.

Definition at line 429 of file txmempool.h.

Member Typedef Documentation

◆ cacheMap

typedef std::map<txiter, setEntries, CompareIteratorByHash> CTxMemPool::cacheMap

private

Definition at line 527 of file txmempool.h.

◆ indexed_transaction_set

typedef boost::multi_index_container< CTxMemPoolEntry, boost::multi_index::indexed_by< boost::multi_index::hashed_unique<mempoolentry_txid, SaltedTxidHasher>, boost::multi_index::hashed_unique< boost::multi_index::tag<index_by_wtxid>, mempoolentry_wtxid, SaltedTxidHasher >, boost::multi_index::ordered_non_unique< boost::multi_index::tag<descendant_score>, boost::multi_index::identity<CTxMemPoolEntry>, CompareTxMemPoolEntryByDescendantScore >, boost::multi_index::ordered_non_unique< boost::multi_index::tag<entry_time>, boost::multi_index::identity<CTxMemPoolEntry>, CompareTxMemPoolEntryByEntryTime >, boost::multi_index::ordered_non_unique< boost::multi_index::tag<ancestor_score>, boost::multi_index::identity<CTxMemPoolEntry>, CompareTxMemPoolEntryByAncestorFee > > > CTxMemPool::indexed_transaction_set

Definition at line 488 of file txmempool.h.

◆ setEntries

typedef std::set<txiter, CompareIteratorByHash> CTxMemPool::setEntries

Definition at line 523 of file txmempool.h.

◆ txiter

using CTxMemPool::txiter = indexed_transaction_set::nth_index<0>::type::const_iterator

Definition at line 520 of file txmempool.h.

Constructor & Destructor Documentation

◆ CTxMemPool()

CTxMemPool::CTxMemPool	(	CBlockPolicyEstimator *	estimator = `nullptr`,
		int	check_ratio = `0`
	)

explicit

Create a new CTxMemPool.

Sanity checks will be off by default for performance, because otherwise accepting transactions becomes O(N^2) where N is the number of transactions in the pool.

Parameters

[in]	estimator	is used to estimate appropriate transaction fees.
[in]	check_ratio	is the ratio used to determine how often sanity checks will run.

Definition at line 454 of file txmempool.cpp.

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Member Function Documentation

◆ _clear()

void CTxMemPool::_clear ( )

Definition at line 693 of file txmempool.cpp.

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◆ AddTransactionsUpdated()

void CTxMemPool::AddTransactionsUpdated ( unsigned int n )

Definition at line 471 of file txmempool.cpp.

◆ AddUnbroadcastTx()

void CTxMemPool::AddUnbroadcastTx ( const uint256 & txid )

inline

Adds a transaction to the unbroadcast set.

Definition at line 768 of file txmempool.h.

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◆ addUnchecked()

void CTxMemPool::addUnchecked	(	const CTxMemPoolEntry &	entry,
		setEntries &	setAncestors,
		bool	validFeeEstimate = `true`
	)

◆ ApplyDelta()

void CTxMemPool::ApplyDelta	(	const uint256 &	hash,
		CAmount &	nFeeDelta
	)		const

Definition at line 945 of file txmempool.cpp.

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◆ CalculateAncestorsAndCheckLimits()

bool CTxMemPool::CalculateAncestorsAndCheckLimits	(	size_t	entry_size,
		size_t	entry_count,
		setEntries &	setAncestors,
		CTxMemPoolEntry::Parents &	staged_ancestors,
		uint64_t	limitAncestorCount,
		uint64_t	limitAncestorSize,
		uint64_t	limitDescendantCount,
		uint64_t	limitDescendantSize,
		std::string &	errString
	)		const

private

Helper function to calculate all in-mempool ancestors of staged_ancestors and apply ancestor and descendant limits (including staged_ancestors thsemselves, entry_size and entry_count).

param@[in] entry_size Virtual size to include in the limits. param@[in] entry_count How many entries to include in the limits. param@[in] staged_ancestors Should contain entries in the mempool. param@[out] setAncestors Will be populated with all mempool ancestors.

Definition at line 214 of file txmempool.cpp.

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◆ CalculateDescendantMaximum()

uint64_t CTxMemPool::CalculateDescendantMaximum ( txiter entry ) const

Definition at line 1170 of file txmempool.cpp.

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◆ CalculateDescendants()

void CTxMemPool::CalculateDescendants	(	txiter	it,
		setEntries &	setDescendants
	)		const

Populate setDescendants with all in-mempool descendants of hash.

Assumes that setDescendants includes all in-mempool descendants of anything already in it.

Definition at line 570 of file txmempool.cpp.

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◆ CalculateMemPoolAncestors()

bool CTxMemPool::CalculateMemPoolAncestors	(	const CTxMemPoolEntry &	entry,
		setEntries &	setAncestors,
		uint64_t	limitAncestorCount,
		uint64_t	limitAncestorSize,
		uint64_t	limitDescendantCount,
		uint64_t	limitDescendantSize,
		std::string &	errString,
		bool	fSearchForParents = `true`
	)		const

Try to calculate all in-mempool ancestors of entry.

(these are all calculated including the tx itself) limitAncestorCount = max number of ancestors limitAncestorSize = max size of ancestors limitDescendantCount = max number of descendants any ancestor can have limitDescendantSize = max size of descendants any ancestor can have errString = populated with error reason if any limits are hit fSearchForParents = whether to search a tx's vin for in-mempool parents, or look up parents from mapLinks. Must be true for entries not in the mempool

Definition at line 298 of file txmempool.cpp.

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◆ CheckPackageLimits()

bool CTxMemPool::CheckPackageLimits	(	const Package &	package,
		uint64_t	limitAncestorCount,
		uint64_t	limitAncestorSize,
		uint64_t	limitDescendantCount,
		uint64_t	limitDescendantSize,
		std::string &	errString
	)		const

Calculate all in-mempool ancestors of a set of transactions not already in the mempool and check ancestor and descendant limits.

Heuristics are used to estimate the ancestor and descendant count of all entries if the package were to be added to the mempool. The limits are applied to the union of all package transactions. For example, if the package has 3 transactions and limitAncestorCount = 25, the union of all 3 sets of ancestors (including the transactions themselves) must be <= 22.

Parameters

[in]	package	Transaction package being evaluated for acceptance to mempool. The transactions need not be direct ancestors/descendants of each other.
[in]	limitAncestorCount	Max number of txns including ancestors.
[in]	limitAncestorSize	Max virtual size including ancestors.
[in]	limitDescendantCount	Max number of txns including descendants.
[in]	limitDescendantSize	Max virtual size including descendants.
[out]	errString	Populated with error reason if a limit is hit.

Definition at line 263 of file txmempool.cpp.

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◆ clear()

void CTxMemPool::clear ( )

Definition at line 707 of file txmempool.cpp.

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◆ ClearPrioritisation()

void CTxMemPool::ClearPrioritisation ( const uint256 & hash )

Definition at line 955 of file txmempool.cpp.

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◆ CompareDepthAndScore()

bool CTxMemPool::CompareDepthAndScore	(	const uint256 &	hasha,
		const uint256 &	hashb,
		bool	wtxid = `false`
	)

Definition at line 821 of file txmempool.cpp.

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◆ DynamicMemoryUsage()

size_t CTxMemPool::DynamicMemoryUsage ( ) const

Definition at line 1024 of file txmempool.cpp.

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◆ exists()

bool CTxMemPool::exists ( const GenTxid & gtxid ) const

inline

Definition at line 747 of file txmempool.h.

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◆ Expire()

int CTxMemPool::Expire ( std::chrono::seconds time )

Expire all transaction (and their dependencies) in the mempool older than time.

Return the number of removed transactions.

Definition at line 1047 of file txmempool.cpp.

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◆ get()

CTransactionRef CTxMemPool::get ( const uint256 & hash ) const

Definition at line 897 of file txmempool.cpp.

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◆ get_iter_from_wtxid()

txiter CTxMemPool::get_iter_from_wtxid ( const uint256 & wtxid ) const

inline

Definition at line 757 of file txmempool.h.

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◆ GetAndIncrementSequence()

uint64_t CTxMemPool::GetAndIncrementSequence ( ) const

inline

Guards this internal counter for external reporting.

Definition at line 794 of file txmempool.h.

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◆ GetConflictTx()

const CTransaction * CTxMemPool::GetConflictTx ( const COutPoint & prevout ) const

Get the transaction in the pool that spends the same prevout.

Definition at line 961 of file txmempool.cpp.

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◆ GetIter()

std::optional< CTxMemPool::txiter > CTxMemPool::GetIter ( const uint256 & txid ) const

Returns an iterator to the given hash, if found.

Definition at line 967 of file txmempool.cpp.

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◆ GetIterSet()

CTxMemPool::setEntries CTxMemPool::GetIterSet ( const std::set< uint256 > & hashes ) const

Translate a set of hashes into a set of pool iterators to avoid repeated lookups.

Definition at line 974 of file txmempool.cpp.

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◆ GetMinFee()

CFeeRate CTxMemPool::GetMinFee ( size_t sizelimit ) const

The minimum fee to get into the mempool, which may itself not be enough for larger-sized transactions.

The incrementalRelayFee policy variable is used to bound the time it takes the fee rate to go back down all the way to 0. When the feerate would otherwise be half of this, it is set to 0 instead.

Definition at line 1095 of file txmempool.cpp.

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◆ GetSequence()

uint64_t CTxMemPool::GetSequence ( ) const

inline

Definition at line 798 of file txmempool.h.

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◆ GetSortedDepthAndScore()

std::vector< CTxMemPool::indexed_transaction_set::const_iterator > CTxMemPool::GetSortedDepthAndScore ( ) const

private

Definition at line 852 of file txmempool.cpp.

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◆ GetTotalFee()

CAmount CTxMemPool::GetTotalFee ( ) const

inline

Definition at line 741 of file txmempool.h.

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◆ GetTotalTxSize()

uint64_t CTxMemPool::GetTotalTxSize ( ) const

inline

Definition at line 735 of file txmempool.h.

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◆ GetTransactionAncestry()

void CTxMemPool::GetTransactionAncestry	(	const uint256 &	txid,
		size_t &	ancestors,
		size_t &	descendants,
		size_t *	ancestorsize = `nullptr`,
		CAmount *	ancestorfees = `nullptr`
	)		const

Calculate the ancestor and descendant count for the given transaction.

The counts include the transaction itself. When ancestors is non-zero (ie, the transaction itself is in the mempool), ancestorsize and ancestorfees will also be set to the appropriate values.

Definition at line 1192 of file txmempool.cpp.

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◆ GetTransactionsUpdated()

unsigned int CTxMemPool::GetTransactionsUpdated ( ) const

Definition at line 466 of file txmempool.cpp.

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◆ GetUnbroadcastTxs()

std::set<uint256> CTxMemPool::GetUnbroadcastTxs ( ) const

inline

Returns transactions in unbroadcast set.

Definition at line 780 of file txmempool.h.

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◆ GUARDED_BY() [1/14]

uint64_t totalTxSize CTxMemPool::GUARDED_BY ( cs )

protected

sum of all mempool tx's virtual sizes. Differs from serialized tx size since witness data is discounted. Defined in BIP 141.

◆ GUARDED_BY() [2/14]

CAmount m_total_fee CTxMemPool::GUARDED_BY ( cs )

protected

sum of all mempool tx's fees (NOT modified fee)

◆ GUARDED_BY() [3/14]

uint64_t cachedInnerUsage CTxMemPool::GUARDED_BY ( cs )

protected

sum of dynamic memory usage of all the map elements (NOT the maps themselves)

◆ GUARDED_BY() [4/14]

int64_t lastRollingFeeUpdate CTxMemPool::GUARDED_BY ( cs )

mutableprotected

◆ GUARDED_BY() [5/14]

bool blockSinceLastRollingFeeBump CTxMemPool::GUARDED_BY ( cs )

mutableprotected

◆ GUARDED_BY() [6/14]

double rollingMinimumFeeRate CTxMemPool::GUARDED_BY ( cs )

mutableprotected

minimum fee to get into the pool, decreases exponentially

◆ GUARDED_BY() [7/14]

Epoch m_epoch CTxMemPool::GUARDED_BY ( cs )

mutableprotected

◆ GUARDED_BY() [8/14]

uint64_t m_sequence_number CTxMemPool::GUARDED_BY ( cs )

inlinemutableprotected

Definition at line 448 of file txmempool.h.

◆ GUARDED_BY() [9/14]

bool m_is_loaded CTxMemPool::GUARDED_BY ( cs )

inlineprotected

Definition at line 452 of file txmempool.h.

◆ GUARDED_BY() [10/14]

indexed_transaction_set mapTx CTxMemPool::GUARDED_BY ( cs )

◆ GUARDED_BY() [11/14]

std::vector<std::pair<uint256, txiter> > vTxHashes CTxMemPool::GUARDED_BY ( cs )

All tx witness hashes/entries in mapTx, in random order.

◆ GUARDED_BY() [12/14]

std::set<uint256> m_unbroadcast_txids CTxMemPool::GUARDED_BY ( cs )

private

Track locally submitted transactions to periodically retry initial broadcast.

◆ GUARDED_BY() [13/14]

indirectmap<COutPoint, const CTransaction*> mapNextTx CTxMemPool::GUARDED_BY ( cs )

◆ GUARDED_BY() [14/14]

std::map<uint256, CAmount> mapDeltas CTxMemPool::GUARDED_BY ( cs )

◆ HasNoInputsOf()

bool CTxMemPool::HasNoInputsOf ( const CTransaction & tx ) const

Check that none of this transactions inputs are in the mempool, and thus the tx is not dependent on other mempool transactions to be included in a block.

Definition at line 984 of file txmempool.cpp.

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◆ info()

TxMempoolInfo CTxMemPool::info ( const GenTxid & gtxid ) const

Definition at line 906 of file txmempool.cpp.

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◆ infoAll()

std::vector< TxMempoolInfo > CTxMemPool::infoAll ( ) const

Definition at line 883 of file txmempool.cpp.

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◆ IsLoaded()

bool CTxMemPool::IsLoaded ( ) const

Returns: true if the mempool is fully loaded

Definition at line 1204 of file txmempool.cpp.

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◆ isSpent()

bool CTxMemPool::isSpent ( const COutPoint & outpoint ) const

Definition at line 460 of file txmempool.cpp.

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◆ IsUnbroadcastTx()

bool CTxMemPool::IsUnbroadcastTx ( const uint256 & txid ) const

inline

Returns whether a txid is in the unbroadcast set.

Definition at line 787 of file txmempool.h.

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◆ LOCKS_EXCLUDED()

void cs_main CTxMemPool::LOCKS_EXCLUDED ( m_epoch )

◆ PrioritiseTransaction()

void CTxMemPool::PrioritiseTransaction	(	const uint256 &	hash,
		const CAmount &	nFeeDelta
	)

Affect CreateNewBlock prioritisation of transactions.

Definition at line 915 of file txmempool.cpp.

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◆ queryHashes()

void CTxMemPool::queryHashes ( std::vector< uint256 > & vtxid ) const

Definition at line 866 of file txmempool.cpp.

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◆ removeConflicts()

void CTxMemPool::removeConflicts ( const CTransaction & tx )

Definition at line 644 of file txmempool.cpp.

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◆ removeForBlock()

void CTxMemPool::removeForBlock	(	const std::vector< CTransactionRef > &	vtx,
		unsigned int	nBlockHeight
	)

Called when a block is connected.

Removes from mempool and updates the miner fee estimator.

Definition at line 664 of file txmempool.cpp.

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◆ removeForReorg()

void CTxMemPool::removeForReorg	(	CChain &	chain,
		std::function< bool(txiter)>	filter_final_and_mature
	)

After reorg, filter the entries that would no longer be valid in the next block, and update the entries' cached LockPoints if needed.

The mempool does not have any knowledge of consensus rules. It just appplies the callable function and removes the ones for which it returns true.

Parameters

[in] filter_final_and_mature Predicate that checks the relevant validation rules and updates an entry's LockPoints.

Definition at line 624 of file txmempool.cpp.

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◆ removeRecursive()

void CTxMemPool::removeRecursive	(	const CTransaction &	tx,
		MemPoolRemovalReason	reason
	)

Definition at line 594 of file txmempool.cpp.

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◆ RemoveStaged()

void CTxMemPool::RemoveStaged	(	setEntries &	stage,
		bool	updateDescendants,
		MemPoolRemovalReason	reason
	)

Remove a set of transactions from the mempool.

If a transaction is in this set, then all in-mempool descendants must also be in the set, unless this transaction is being removed for being in a block. Set updateDescendants to true when removing a tx that was in a block, so that any in-mempool descendants have their ancestor state updated.

Definition at line 1039 of file txmempool.cpp.

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◆ RemoveUnbroadcastTx()

void CTxMemPool::RemoveUnbroadcastTx	(	const uint256 &	txid,
		const bool	unchecked = `false`
	)

Removes a transaction from the unbroadcast set.

Definition at line 1030 of file txmempool.cpp.

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◆ removeUnchecked()

void CTxMemPool::removeUnchecked	(	txiter	entry,
		MemPoolRemovalReason	reason
	)

private

Before calling removeUnchecked for a given transaction, UpdateForRemoveFromMempool must be called on the entire (dependent) set of transactions being removed at the same time.

We use each CTxMemPoolEntry's setMemPoolParents in order to walk ancestors of a given transaction that is removed, so we can't remove intermediate transactions in a chain before we've updated all the state for the removal.

Definition at line 526 of file txmempool.cpp.

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◆ SetIsLoaded()

void CTxMemPool::SetIsLoaded ( bool loaded )

Sets the current loaded state.

Definition at line 1210 of file txmempool.cpp.

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◆ size()

unsigned long CTxMemPool::size ( ) const

inline

Definition at line 729 of file txmempool.h.

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◆ trackPackageRemoved()

void CTxMemPool::trackPackageRemoved ( const CFeeRate & rate )

protected

Definition at line 1119 of file txmempool.cpp.

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◆ TrimToSize()

void CTxMemPool::TrimToSize	(	size_t	sizelimit,
		std::vector< COutPoint > *	pvNoSpendsRemaining = `nullptr`
	)

Remove transactions from the mempool until its dynamic size is <= sizelimit.

pvNoSpendsRemaining, if set, will be populated with the list of outpoints which are not in mempool which no longer have any spends in this mempool.

Definition at line 1127 of file txmempool.cpp.

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◆ UpdateAncestorsOf()

void CTxMemPool::UpdateAncestorsOf	(	bool	add,
		txiter	hash,
		setEntries &	setAncestors
	)

private

Update ancestors of hash to add/remove it as a descendant transaction.

Definition at line 337 of file txmempool.cpp.

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◆ UpdateChild()

void CTxMemPool::UpdateChild	(	txiter	entry,
		txiter	child,
		bool	add
	)

private

Definition at line 1073 of file txmempool.cpp.

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◆ UpdateChildrenForRemoval()

void CTxMemPool::UpdateChildrenForRemoval ( txiter entry )

private

Sever link between specified transaction and direct children.

Definition at line 366 of file txmempool.cpp.

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◆ UpdateEntryForAncestors()

void CTxMemPool::UpdateEntryForAncestors	(	txiter	it,
		const setEntries &	setAncestors
	)

private

Set ancestor state for an entry.

Definition at line 352 of file txmempool.cpp.

◆ UpdateForDescendants()

void CTxMemPool::UpdateForDescendants	(	txiter	updateIt,
		cacheMap &	cachedDescendants,
		const std::set< uint256 > &	setExclude,
		std::set< uint256 > &	descendants_to_remove,
		uint64_t	ancestor_size_limit,
		uint64_t	ancestor_count_limit
	)

private

UpdateForDescendants is used by UpdateTransactionsFromBlock to update the descendants for a single transaction that has been added to the mempool but may have child transactions in the mempool, eg during a chain reorg.

Precondition: CTxMemPool::m_children is correct for the given tx and all descendants.; cachedDescendants is an accurate cache where each entry has all descendants of the corresponding key, including those that should be removed for violation of ancestor limits.

Postcondition: if updateIt has any non-excluded descendants, cachedDescendants has a new cache line for updateIt.; descendants_to_remove has a new entry for any descendant which exceeded ancestor limits relative to updateIt.

Parameters

[in]	updateIt	the entry to update for its descendants
[in,out]	cachedDescendants	a cache where each line corresponds to all descendants. It will be updated with the descendants of the transaction being updated, so that future invocations don't need to walk the same transaction again, if encountered in another transaction chain.
[in]	setExclude	the set of descendant transactions in the mempool that must not be accounted for (because any descendants in setExclude were added to the mempool after the transaction being updated and hence their state is already reflected in the parent state).
[out]	descendants_to_remove	Populated with the txids of entries that exceed ancestor limits. It's the responsibility of the caller to removeRecursive them.
[in]	ancestor_size_limit	the max number of ancestral bytes allowed for any descendant
[in]	ancestor_count_limit	the max number of ancestor transactions allowed for any descendant

Definition at line 109 of file txmempool.cpp.

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◆ UpdateForRemoveFromMempool()

void CTxMemPool::UpdateForRemoveFromMempool	(	const setEntries &	entriesToRemove,
		bool	updateDescendants
	)

private

For each transaction being removed, update ancestors and any direct children.

If updateDescendants is true, then also update in-mempool descendants' ancestor state.

Definition at line 374 of file txmempool.cpp.

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◆ UpdateParent()

void CTxMemPool::UpdateParent	(	txiter	entry,
		txiter	parent,
		bool	add
	)

private

Definition at line 1084 of file txmempool.cpp.

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◆ UpdateTransactionsFromBlock()

void CTxMemPool::UpdateTransactionsFromBlock	(	const std::vector< uint256 > &	vHashesToUpdate,
		uint64_t	ancestor_size_limit,
		uint64_t	ancestor_count_limit
	)

UpdateTransactionsFromBlock is called when adding transactions from a disconnected block back to the mempool, new mempool entries may have children in the mempool (which is generally not the case when otherwise adding transactions).

Postcondition: updated descendant state for descendants of each transaction in vHashesToUpdate (excluding any child transactions present in vHashesToUpdate, which are already accounted for). Updated state includes add fee/size information for such descendants to the parent and updated ancestor state to include the parent.

Parameters

[in]	vHashesToUpdate	The set of txids from the disconnected block that have been accepted back into the mempool.
[in]	ancestor_size_limit	The maximum allowed size in virtual bytes of an entry and its ancestors
[in]	ancestor_count_limit	The maximum allowed number of transactions including the entry and its ancestors.

Definition at line 159 of file txmempool.cpp.

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◆ visited() [1/2]

bool CTxMemPool::visited ( const txiter it ) const

visited marks a CTxMemPoolEntry as having been traversed during the lifetime of the most recently created Epoch::Guard and returns false if we are the first visitor, true otherwise.

An Epoch::Guard must be held when visited is called or an assert will be triggered.

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◆ visited() [2/2]

bool CTxMemPool::visited ( std::optional< txiter > it ) const

Member Data Documentation

◆ addUnchecked

void CTxMemPool::addUnchecked

If sanity-checking is turned on, check makes sure the pool is consistent (does not contain two transactions that spend the same inputs, all inputs are in the mapNextTx array).

If sanity-checking is turned off, check does nothing.

Definition at line 588 of file txmempool.h.

◆ cs

RecursiveMutex CTxMemPool::cs

mutable

This mutex needs to be locked when accessing mapTx or other members that are guarded by it.

Consistency guarantees

By design, it is guaranteed that:

Locking both cs_main and mempool.cs will give a view of mempool that is consistent with current chain tip (ActiveChain() and CoinsTip()) and is fully populated. Fully populated means that if the current active chain is missing transactions that were present in a previously active chain, all the missing transactions will have been re-added to the mempool and should be present if they meet size and consistency constraints.
Locking mempool.cs without cs_main will give a view of a mempool consistent with some chain that was active since cs_main was last locked, and that is fully populated as described above. It is ok for code that only needs to query or remove transactions from the mempool to lock just mempool.cs without cs_main.

To provide these guarantees, it is necessary to lock both cs_main and mempool.cs whenever adding transactions to the mempool and whenever changing the chain tip. It's necessary to keep both mutexes locked until the mempool is consistent with the new chain tip and fully populated.

Definition at line 517 of file txmempool.h.

◆ cs_main [1/2]

void CTxMemPool::cs_main

Definition at line 588 of file txmempool.h.

◆ cs_main [2/2]

void CTxMemPool::cs_main

Definition at line 589 of file txmempool.h.

◆ it

return !it visited* CTxMemPool::it

Definition at line 875 of file txmempool.h.

◆ m_check_ratio

const int CTxMemPool::m_check_ratio

protected

Value n means that 1 times in n we check.

Definition at line 432 of file txmempool.h.

◆ m_epoch

bool CTxMemPool::m_epoch

Initial value:

{

return m_epoch.visited(it->m_epoch_marker)

Definition at line 868 of file txmempool.h.

◆ minerPolicyEstimator

CBlockPolicyEstimator* const CTxMemPool::minerPolicyEstimator

protected

Definition at line 434 of file txmempool.h.

◆ nTransactionsUpdated

std::atomic<unsigned int> CTxMemPool::nTransactionsUpdated {0}

protected

Used by getblocktemplate to trigger CreateNewBlock() invocation.

Definition at line 433 of file txmempool.h.

◆ ROLLING_FEE_HALFLIFE

const int CTxMemPool::ROLLING_FEE_HALFLIFE = 60 * 60 * 12

static

Definition at line 456 of file txmempool.h.

The documentation for this class was generated from the following files:

src/txmempool.h
src/txmempool.cpp

Public Types

Public Member Functions

Public Attributes

Static Public Attributes

Protected Member Functions

Protected Attributes

Private Types

Private Member Functions

Detailed Description

Member Typedef Documentation

◆ cacheMap

◆ indexed_transaction_set

◆ setEntries

◆ txiter

Constructor & Destructor Documentation

◆ CTxMemPool()

Member Function Documentation

◆ _clear()

◆ AddTransactionsUpdated()

◆ AddUnbroadcastTx()

◆ addUnchecked()

◆ ApplyDelta()

◆ CalculateAncestorsAndCheckLimits()

◆ CalculateDescendantMaximum()

◆ CalculateDescendants()

◆ CalculateMemPoolAncestors()

◆ CheckPackageLimits()

◆ clear()

◆ ClearPrioritisation()

◆ CompareDepthAndScore()

◆ DynamicMemoryUsage()

◆ exists()

◆ Expire()

◆ get()

◆ get_iter_from_wtxid()

◆ GetAndIncrementSequence()

◆ GetConflictTx()

◆ GetIter()

◆ GetIterSet()

◆ GetMinFee()

◆ GetSequence()

◆ GetSortedDepthAndScore()

◆ GetTotalFee()

◆ GetTotalTxSize()

◆ GetTransactionAncestry()

◆ GetTransactionsUpdated()

◆ GetUnbroadcastTxs()

◆ GUARDED_BY() [1/14]

◆ GUARDED_BY() [2/14]

◆ GUARDED_BY() [3/14]

◆ GUARDED_BY() [4/14]

◆ GUARDED_BY() [5/14]

◆ GUARDED_BY() [6/14]

◆ GUARDED_BY() [7/14]

◆ GUARDED_BY() [8/14]

◆ GUARDED_BY() [9/14]

◆ GUARDED_BY() [10/14]

◆ GUARDED_BY() [11/14]

◆ GUARDED_BY() [12/14]

◆ GUARDED_BY() [13/14]

◆ GUARDED_BY() [14/14]

◆ HasNoInputsOf()

◆ info()

◆ infoAll()

◆ IsLoaded()

◆ isSpent()

◆ IsUnbroadcastTx()

◆ LOCKS_EXCLUDED()

◆ PrioritiseTransaction()

◆ queryHashes()

◆ removeConflicts()

◆ removeForBlock()

◆ removeForReorg()

◆ removeRecursive()

◆ RemoveStaged()

◆ RemoveUnbroadcastTx()

◆ removeUnchecked()

◆ SetIsLoaded()

◆ size()

◆ trackPackageRemoved()