Track transaction packages in CTxMemPoolEntry

Associate with each CTxMemPoolEntry all the size/fees of descendant
mempool transactions.  Sort mempool by max(feerate of entry, feerate
of descendants).  Update statistics on-the-fly as transactions enter
or leave the mempool.

Also add ancestor and descendant limiting, so that transactions can
be rejected if the number or size of unconfirmed ancestors exceeds
a target, or if adding a transaction would cause some other mempool
entry to have too many (or too large) a set of unconfirmed in-
mempool descendants.
This commit is contained in:
Suhas Daftuar 2015-07-15 14:47:45 -04:00 committed by Suhas Daftuar
parent 34628a1807
commit 5add7a74a6
10 changed files with 993 additions and 65 deletions

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@ -57,6 +57,7 @@ testScriptsExt=(
'invalidblockrequest.py'
# 'forknotify.py'
'p2p-acceptblock.py'
'mempool_packages.py'
);
#if [ "x$ENABLE_ZMQ" = "x1" ]; then

107
qa/rpc-tests/mempool_packages.py Executable file
View file

@ -0,0 +1,107 @@
#!/usr/bin/env python2
# Copyright (c) 2014-2015 The Bitcoin Core developers
# Distributed under the MIT software license, see the accompanying
# file COPYING or http://www.opensource.org/licenses/mit-license.php.
# Test descendant package tracking code
from test_framework.test_framework import BitcoinTestFramework
from test_framework.util import *
def satoshi_round(amount):
return Decimal(amount).quantize(Decimal('0.00000001'), rounding=ROUND_DOWN)
class MempoolPackagesTest(BitcoinTestFramework):
def setup_network(self):
self.nodes = []
self.nodes.append(start_node(0, self.options.tmpdir, ["-maxorphantx=1000", "-relaypriority=0"]))
self.is_network_split = False
self.sync_all()
# Build a transaction that spends parent_txid:vout
# Return amount sent
def chain_transaction(self, parent_txid, vout, value, fee, num_outputs):
send_value = satoshi_round((value - fee)/num_outputs)
inputs = [ {'txid' : parent_txid, 'vout' : vout} ]
outputs = {}
for i in xrange(num_outputs):
outputs[self.nodes[0].getnewaddress()] = send_value
rawtx = self.nodes[0].createrawtransaction(inputs, outputs)
signedtx = self.nodes[0].signrawtransaction(rawtx)
txid = self.nodes[0].sendrawtransaction(signedtx['hex'])
fulltx = self.nodes[0].getrawtransaction(txid, 1)
assert(len(fulltx['vout']) == num_outputs) # make sure we didn't generate a change output
return (txid, send_value)
def run_test(self):
''' Mine some blocks and have them mature. '''
self.nodes[0].generate(101)
utxo = self.nodes[0].listunspent(10)
txid = utxo[0]['txid']
vout = utxo[0]['vout']
value = utxo[0]['amount']
fee = Decimal("0.0001")
# 100 transactions off a confirmed tx should be fine
chain = []
for i in xrange(100):
(txid, sent_value) = self.chain_transaction(txid, 0, value, fee, 1)
value = sent_value
chain.append(txid)
# Check mempool has 100 transactions in it, and descendant
# count and fees should look correct
mempool = self.nodes[0].getrawmempool(True)
assert_equal(len(mempool), 100)
descendant_count = 1
descendant_fees = 0
descendant_size = 0
SATOSHIS = 100000000
for x in reversed(chain):
assert_equal(mempool[x]['descendantcount'], descendant_count)
descendant_fees += mempool[x]['fee']
assert_equal(mempool[x]['descendantfees'], SATOSHIS*descendant_fees)
descendant_size += mempool[x]['size']
assert_equal(mempool[x]['descendantsize'], descendant_size)
descendant_count += 1
# Adding one more transaction on to the chain should fail.
try:
self.chain_transaction(txid, vout, value, fee, 1)
except JSONRPCException as e:
print "too-long-ancestor-chain successfully rejected"
# TODO: test ancestor size limits
# Now test descendant chain limits
txid = utxo[1]['txid']
value = utxo[1]['amount']
vout = utxo[1]['vout']
transaction_package = []
# First create one parent tx with 10 children
(txid, sent_value) = self.chain_transaction(txid, vout, value, fee, 10)
parent_transaction = txid
for i in xrange(10):
transaction_package.append({'txid': txid, 'vout': i, 'amount': sent_value})
for i in xrange(1000):
utxo = transaction_package.pop(0)
try:
(txid, sent_value) = self.chain_transaction(utxo['txid'], utxo['vout'], utxo['amount'], fee, 10)
for j in xrange(10):
transaction_package.append({'txid': txid, 'vout': j, 'amount': sent_value})
if i == 998:
mempool = self.nodes[0].getrawmempool(True)
assert_equal(mempool[parent_transaction]['descendantcount'], 1000)
except JSONRPCException as e:
print e.error['message']
assert_equal(i, 999)
print "tx that would create too large descendant package successfully rejected"
# TODO: test descendant size limits
if __name__ == '__main__':
MempoolPackagesTest().main()

View file

@ -411,6 +411,10 @@ std::string HelpMessage(HelpMessageMode mode)
strUsage += HelpMessageOpt("-fuzzmessagestest=<n>", "Randomly fuzz 1 of every <n> network messages");
strUsage += HelpMessageOpt("-flushwallet", strprintf("Run a thread to flush wallet periodically (default: %u)", 1));
strUsage += HelpMessageOpt("-stopafterblockimport", strprintf("Stop running after importing blocks from disk (default: %u)", 0));
strUsage += HelpMessageOpt("-limitancestorcount=<n>", strprintf("Do not accept transactions if number of in-mempool ancestors is <n> or more (default: %u)", DEFAULT_ANCESTOR_LIMIT));
strUsage += HelpMessageOpt("-limitancestorsize=<n>", strprintf("Do not accept transactions whose size with all in-mempool ancestors exceeds <n> kilobytes (default: %u)", DEFAULT_ANCESTOR_SIZE_LIMIT));
strUsage += HelpMessageOpt("-limitdescendantcount=<n>", strprintf("Do not accept transactions if any ancestor would have <n> or more in-mempool descendants (default: %u)", DEFAULT_DESCENDANT_LIMIT));
strUsage += HelpMessageOpt("-limitdescendantsize=<n>", strprintf("Do not accept transactions if any ancestor would have more than <n> kilobytes of in-mempool descendants (default: %u).", DEFAULT_DESCENDANT_SIZE_LIMIT));
}
string debugCategories = "addrman, alert, bench, coindb, db, lock, rand, rpc, selectcoins, mempool, mempoolrej, net, proxy, prune, http"; // Don't translate these and qt below
if (mode == HMM_BITCOIN_QT)

View file

@ -921,6 +921,17 @@ bool AcceptToMemoryPool(CTxMemPool& pool, CValidationState &state, const CTransa
REJECT_HIGHFEE, "absurdly-high-fee",
strprintf("%d > %d", nFees, ::minRelayTxFee.GetFee(nSize) * 10000));
// Calculate in-mempool ancestors, up to a limit.
CTxMemPool::setEntries setAncestors;
size_t nLimitAncestors = GetArg("-limitancestorcount", DEFAULT_ANCESTOR_LIMIT);
size_t nLimitAncestorSize = GetArg("-limitancestorsize", DEFAULT_ANCESTOR_SIZE_LIMIT)*1000;
size_t nLimitDescendants = GetArg("-limitdescendantcount", DEFAULT_DESCENDANT_LIMIT);
size_t nLimitDescendantSize = GetArg("-limitdescendantsize", DEFAULT_DESCENDANT_SIZE_LIMIT)*1000;
std::string errString;
if (!pool.CalculateMemPoolAncestors(entry, setAncestors, nLimitAncestors, nLimitAncestorSize, nLimitDescendants, nLimitDescendantSize, errString)) {
return state.DoS(0, false, REJECT_NONSTANDARD, "too-long-mempool-chain", false, errString);
}
// Check against previous transactions
// This is done last to help prevent CPU exhaustion denial-of-service attacks.
if (!CheckInputs(tx, state, view, true, STANDARD_SCRIPT_VERIFY_FLAGS, true))
@ -942,7 +953,7 @@ bool AcceptToMemoryPool(CTxMemPool& pool, CValidationState &state, const CTransa
}
// Store transaction in memory
pool.addUnchecked(hash, entry, !IsInitialBlockDownload());
pool.addUnchecked(hash, entry, setAncestors, !IsInitialBlockDownload());
}
SyncWithWallets(tx, NULL);
@ -2033,13 +2044,23 @@ bool static DisconnectTip(CValidationState &state) {
if (!FlushStateToDisk(state, FLUSH_STATE_IF_NEEDED))
return false;
// Resurrect mempool transactions from the disconnected block.
std::vector<uint256> vHashUpdate;
BOOST_FOREACH(const CTransaction &tx, block.vtx) {
// ignore validation errors in resurrected transactions
list<CTransaction> removed;
CValidationState stateDummy;
if (tx.IsCoinBase() || !AcceptToMemoryPool(mempool, stateDummy, tx, false, NULL))
if (tx.IsCoinBase() || !AcceptToMemoryPool(mempool, stateDummy, tx, false, NULL)) {
mempool.remove(tx, removed, true);
} else if (mempool.exists(tx.GetHash())) {
vHashUpdate.push_back(tx.GetHash());
}
}
// AcceptToMemoryPool/addUnchecked all assume that new mempool entries have
// no in-mempool children, which is generally not true when adding
// previously-confirmed transactions back to the mempool.
// UpdateTransactionsFromBlock finds descendants of any transactions in this
// block that were added back and cleans up the mempool state.
mempool.UpdateTransactionsFromBlock(vHashUpdate);
mempool.removeCoinbaseSpends(pcoinsTip, pindexDelete->nHeight);
mempool.check(pcoinsTip);
// Update chainActive and related variables.
@ -4258,7 +4279,7 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv,
LogPrint("mempool", "AcceptToMemoryPool: peer=%d %s: accepted %s (poolsz %u)\n",
pfrom->id, pfrom->cleanSubVer,
tx.GetHash().ToString(),
mempool.mapTx.size());
mempool.size());
// Recursively process any orphan transactions that depended on this one
set<NodeId> setMisbehaving;

View file

@ -43,6 +43,14 @@ struct CNodeStateStats;
static const bool DEFAULT_ALERTS = true;
/** Default for -maxorphantx, maximum number of orphan transactions kept in memory */
static const unsigned int DEFAULT_MAX_ORPHAN_TRANSACTIONS = 100;
/** Default for -limitancestorcount, max number of in-mempool ancestors */
static const unsigned int DEFAULT_ANCESTOR_LIMIT = 100;
/** Default for -limitancestorsize, maximum kilobytes of tx + all in-mempool ancestors */
static const unsigned int DEFAULT_ANCESTOR_SIZE_LIMIT = 900;
/** Default for -limitdescendantcount, max number of in-mempool descendants */
static const unsigned int DEFAULT_DESCENDANT_LIMIT = 1000;
/** Default for -limitdescendantsize, maximum kilobytes of in-mempool descendants */
static const unsigned int DEFAULT_DESCENDANT_SIZE_LIMIT = 2500;
/** The maximum size of a blk?????.dat file (since 0.8) */
static const unsigned int MAX_BLOCKFILE_SIZE = 0x8000000; // 128 MiB
/** The pre-allocation chunk size for blk?????.dat files (since 0.8) */

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@ -74,18 +74,30 @@ static inline size_t DynamicUsage(const std::vector<X>& v)
return MallocUsage(v.capacity() * sizeof(X));
}
template<typename X>
static inline size_t DynamicUsage(const std::set<X>& s)
template<typename X, typename Y>
static inline size_t DynamicUsage(const std::set<X, Y>& s)
{
return MallocUsage(sizeof(stl_tree_node<X>)) * s.size();
}
template<typename X, typename Y>
static inline size_t DynamicUsage(const std::map<X, Y>& m)
static inline size_t IncrementalDynamicUsage(const std::set<X, Y>& s)
{
return MallocUsage(sizeof(stl_tree_node<X>));
}
template<typename X, typename Y, typename Z>
static inline size_t DynamicUsage(const std::map<X, Y, Z>& m)
{
return MallocUsage(sizeof(stl_tree_node<std::pair<const X, Y> >)) * m.size();
}
template<typename X, typename Y, typename Z>
static inline size_t IncrementalDynamicUsage(const std::map<X, Y, Z>& m)
{
return MallocUsage(sizeof(stl_tree_node<std::pair<const X, Y> >));
}
// Boost data structures
template<typename X>

View file

@ -191,6 +191,9 @@ UniValue mempoolToJSON(bool fVerbose = false)
info.push_back(Pair("height", (int)e.GetHeight()));
info.push_back(Pair("startingpriority", e.GetPriority(e.GetHeight())));
info.push_back(Pair("currentpriority", e.GetPriority(chainActive.Height())));
info.push_back(Pair("descendantcount", e.GetCountWithDescendants()));
info.push_back(Pair("descendantsize", e.GetSizeWithDescendants()));
info.push_back(Pair("descendantfees", e.GetFeesWithDescendants()));
const CTransaction& tx = e.GetTx();
set<string> setDepends;
BOOST_FOREACH(const CTxIn& txin, tx.vin)
@ -245,6 +248,9 @@ UniValue getrawmempool(const UniValue& params, bool fHelp)
" \"height\" : n, (numeric) block height when transaction entered pool\n"
" \"startingpriority\" : n, (numeric) priority when transaction entered pool\n"
" \"currentpriority\" : n, (numeric) transaction priority now\n"
" \"descendantcount\" : n, (numeric) number of in-mempool descendant transactions (including this one)\n"
" \"descendantsize\" : n, (numeric) size of in-mempool descendants (including this one)\n"
" \"descendantfees\" : n, (numeric) fees of in-mempool descendants (including this one)\n"
" \"depends\" : [ (array) unconfirmed transactions used as inputs for this transaction\n"
" \"transactionid\", (string) parent transaction id\n"
" ... ]\n"

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@ -9,6 +9,7 @@
#include <boost/test/unit_test.hpp>
#include <list>
#include <vector>
BOOST_FIXTURE_TEST_SUITE(mempool_tests, TestingSetup)
@ -100,6 +101,16 @@ BOOST_AUTO_TEST_CASE(MempoolRemoveTest)
removed.clear();
}
void CheckSort(CTxMemPool &pool, std::vector<std::string> &sortedOrder)
{
BOOST_CHECK_EQUAL(pool.size(), sortedOrder.size());
CTxMemPool::indexed_transaction_set::nth_index<1>::type::iterator it = pool.mapTx.get<1>().begin();
int count=0;
for (; it != pool.mapTx.get<1>().end(); ++it, ++count) {
BOOST_CHECK_EQUAL(it->GetTx().GetHash().ToString(), sortedOrder[count]);
}
}
BOOST_AUTO_TEST_CASE(MempoolIndexingTest)
{
CTxMemPool pool(CFeeRate(0));
@ -138,18 +149,136 @@ BOOST_AUTO_TEST_CASE(MempoolIndexingTest)
tx5.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
tx5.vout[0].nValue = 11 * COIN;
pool.addUnchecked(tx5.GetHash(), CTxMemPoolEntry(tx5, 10000LL, 1, 10.0, 1, true));
// there should be 4 transactions in the mempool
BOOST_CHECK_EQUAL(pool.size(), 5);
// Check the fee-rate index is in order, should be tx2, tx4, tx1, tx5, tx3
CTxMemPool::indexed_transaction_set::nth_index<1>::type::iterator it = pool.mapTx.get<1>().begin();
BOOST_CHECK_EQUAL(it++->GetTx().GetHash().ToString(), tx2.GetHash().ToString());
BOOST_CHECK_EQUAL(it++->GetTx().GetHash().ToString(), tx4.GetHash().ToString());
BOOST_CHECK_EQUAL(it++->GetTx().GetHash().ToString(), tx1.GetHash().ToString());
BOOST_CHECK_EQUAL(it++->GetTx().GetHash().ToString(), tx5.GetHash().ToString());
BOOST_CHECK_EQUAL(it++->GetTx().GetHash().ToString(), tx3.GetHash().ToString());
BOOST_CHECK(it == pool.mapTx.get<1>().end());
std::vector<std::string> sortedOrder;
sortedOrder.resize(5);
sortedOrder[0] = tx2.GetHash().ToString(); // 20000
sortedOrder[1] = tx4.GetHash().ToString(); // 15000
sortedOrder[2] = tx1.GetHash().ToString(); // 10000
sortedOrder[3] = tx5.GetHash().ToString(); // 10000
sortedOrder[4] = tx3.GetHash().ToString(); // 0
CheckSort(pool, sortedOrder);
/* low fee but with high fee child */
/* tx6 -> tx7 -> tx8, tx9 -> tx10 */
CMutableTransaction tx6 = CMutableTransaction();
tx6.vout.resize(1);
tx6.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
tx6.vout[0].nValue = 20 * COIN;
pool.addUnchecked(tx6.GetHash(), CTxMemPoolEntry(tx6, 0LL, 1, 10.0, 1, true));
BOOST_CHECK_EQUAL(pool.size(), 6);
// Check that at this point, tx6 is sorted low
sortedOrder.push_back(tx6.GetHash().ToString());
CheckSort(pool, sortedOrder);
CTxMemPool::setEntries setAncestors;
setAncestors.insert(pool.mapTx.find(tx6.GetHash()));
CMutableTransaction tx7 = CMutableTransaction();
tx7.vin.resize(1);
tx7.vin[0].prevout = COutPoint(tx6.GetHash(), 0);
tx7.vin[0].scriptSig = CScript() << OP_11;
tx7.vout.resize(2);
tx7.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
tx7.vout[0].nValue = 10 * COIN;
tx7.vout[1].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
tx7.vout[1].nValue = 1 * COIN;
CTxMemPool::setEntries setAncestorsCalculated;
std::string dummy;
CTxMemPoolEntry entry7(tx7, 2000000LL, 1, 10.0, 1, true);
BOOST_CHECK_EQUAL(pool.CalculateMemPoolAncestors(entry7, setAncestorsCalculated, 100, 1000000, 1000, 1000000, dummy), true);
BOOST_CHECK(setAncestorsCalculated == setAncestors);
pool.addUnchecked(tx7.GetHash(), CTxMemPoolEntry(tx7, 2000000LL, 1, 10.0, 1, true), setAncestors);
BOOST_CHECK_EQUAL(pool.size(), 7);
// Now tx6 should be sorted higher (high fee child): tx7, tx6, tx2, ...
sortedOrder.erase(sortedOrder.end()-1);
sortedOrder.insert(sortedOrder.begin(), tx6.GetHash().ToString());
sortedOrder.insert(sortedOrder.begin(), tx7.GetHash().ToString());
CheckSort(pool, sortedOrder);
/* low fee child of tx7 */
CMutableTransaction tx8 = CMutableTransaction();
tx8.vin.resize(1);
tx8.vin[0].prevout = COutPoint(tx7.GetHash(), 0);
tx8.vin[0].scriptSig = CScript() << OP_11;
tx8.vout.resize(1);
tx8.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
tx8.vout[0].nValue = 10 * COIN;
setAncestors.insert(pool.mapTx.find(tx7.GetHash()));
pool.addUnchecked(tx8.GetHash(), CTxMemPoolEntry(tx8, 0LL, 2, 10.0, 1, true), setAncestors);
// Now tx8 should be sorted low, but tx6/tx both high
sortedOrder.push_back(tx8.GetHash().ToString());
CheckSort(pool, sortedOrder);
/* low fee child of tx7 */
CMutableTransaction tx9 = CMutableTransaction();
tx9.vin.resize(1);
tx9.vin[0].prevout = COutPoint(tx7.GetHash(), 1);
tx9.vin[0].scriptSig = CScript() << OP_11;
tx9.vout.resize(1);
tx9.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
tx9.vout[0].nValue = 1 * COIN;
pool.addUnchecked(tx9.GetHash(), CTxMemPoolEntry(tx9, 0LL, 3, 10.0, 1, true), setAncestors);
// tx9 should be sorted low
BOOST_CHECK_EQUAL(pool.size(), 9);
sortedOrder.push_back(tx9.GetHash().ToString());
CheckSort(pool, sortedOrder);
std::vector<std::string> snapshotOrder = sortedOrder;
setAncestors.insert(pool.mapTx.find(tx8.GetHash()));
setAncestors.insert(pool.mapTx.find(tx9.GetHash()));
/* tx10 depends on tx8 and tx9 and has a high fee*/
CMutableTransaction tx10 = CMutableTransaction();
tx10.vin.resize(2);
tx10.vin[0].prevout = COutPoint(tx8.GetHash(), 0);
tx10.vin[0].scriptSig = CScript() << OP_11;
tx10.vin[1].prevout = COutPoint(tx9.GetHash(), 0);
tx10.vin[1].scriptSig = CScript() << OP_11;
tx10.vout.resize(1);
tx10.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
tx10.vout[0].nValue = 10 * COIN;
setAncestorsCalculated.clear();
CTxMemPoolEntry entry10(tx10, 200000LL, 4, 10.0, 1, true);
BOOST_CHECK_EQUAL(pool.CalculateMemPoolAncestors(entry10, setAncestorsCalculated, 100, 1000000, 1000, 1000000, dummy), true);
BOOST_CHECK(setAncestorsCalculated == setAncestors);
pool.addUnchecked(tx10.GetHash(), CTxMemPoolEntry(tx10, 200000LL, 4, 10.0, 1, true), setAncestors);
/**
* tx8 and tx9 should both now be sorted higher
* Final order after tx10 is added:
*
* tx7 = 2.2M (4 txs)
* tx6 = 2.2M (5 txs)
* tx10 = 200k (1 tx)
* tx8 = 200k (2 txs)
* tx9 = 200k (2 txs)
* tx2 = 20000 (1)
* tx4 = 15000 (1)
* tx1 = 10000 (1)
* tx5 = 10000 (1)
* tx3 = 0 (1)
*/
sortedOrder.erase(sortedOrder.end()-2, sortedOrder.end()); // take out tx8, tx9 from the end
sortedOrder.insert(sortedOrder.begin()+2, tx10.GetHash().ToString()); // tx10 is after tx6
sortedOrder.insert(sortedOrder.begin()+3, tx9.GetHash().ToString());
sortedOrder.insert(sortedOrder.begin()+3, tx8.GetHash().ToString());
CheckSort(pool, sortedOrder);
// there should be 10 transactions in the mempool
BOOST_CHECK_EQUAL(pool.size(), 10);
// Now try removing tx10 and verify the sort order returns to normal
std::list<CTransaction> removed;
pool.remove(pool.mapTx.find(tx10.GetHash())->GetTx(), removed, true);
CheckSort(pool, snapshotOrder);
}
BOOST_AUTO_TEST_SUITE_END()

View file

@ -17,12 +17,6 @@
using namespace std;
CTxMemPoolEntry::CTxMemPoolEntry():
nFee(0), nTxSize(0), nModSize(0), nUsageSize(0), nTime(0), dPriority(0.0), hadNoDependencies(false)
{
nHeight = MEMPOOL_HEIGHT;
}
CTxMemPoolEntry::CTxMemPoolEntry(const CTransaction& _tx, const CAmount& _nFee,
int64_t _nTime, double _dPriority,
unsigned int _nHeight, bool poolHasNoInputsOf):
@ -32,7 +26,10 @@ CTxMemPoolEntry::CTxMemPoolEntry(const CTransaction& _tx, const CAmount& _nFee,
nTxSize = ::GetSerializeSize(tx, SER_NETWORK, PROTOCOL_VERSION);
nModSize = tx.CalculateModifiedSize(nTxSize);
nUsageSize = RecursiveDynamicUsage(tx);
feeRate = CFeeRate(nFee, nTxSize);
nCountWithDescendants = 1;
nSizeWithDescendants = nTxSize;
nFeesWithDescendants = nFee;
}
CTxMemPoolEntry::CTxMemPoolEntry(const CTxMemPoolEntry& other)
@ -49,6 +46,244 @@ CTxMemPoolEntry::GetPriority(unsigned int currentHeight) const
return dResult;
}
// Update the given tx for any in-mempool descendants.
// Assumes that setMemPoolChildren is correct for the given tx and all
// descendants.
bool CTxMemPool::UpdateForDescendants(txiter updateIt, int maxDescendantsToVisit, cacheMap &cachedDescendants, const std::set<uint256> &setExclude)
{
// Track the number of entries (outside setExclude) that we'd need to visit
// (will bail out if it exceeds maxDescendantsToVisit)
int nChildrenToVisit = 0;
setEntries stageEntries, setAllDescendants;
stageEntries = GetMemPoolChildren(updateIt);
while (!stageEntries.empty()) {
const txiter cit = *stageEntries.begin();
if (cit->IsDirty()) {
// Don't consider any more children if any descendant is dirty
return false;
}
setAllDescendants.insert(cit);
stageEntries.erase(cit);
const setEntries &setChildren = GetMemPoolChildren(cit);
BOOST_FOREACH(const txiter childEntry, setChildren) {
cacheMap::iterator cacheIt = cachedDescendants.find(childEntry);
if (cacheIt != cachedDescendants.end()) {
// We've already calculated this one, just add the entries for this set
// but don't traverse again.
BOOST_FOREACH(const txiter cacheEntry, cacheIt->second) {
// update visit count only for new child transactions
// (outside of setExclude and stageEntries)
if (setAllDescendants.insert(cacheEntry).second &&
!setExclude.count(cacheEntry->GetTx().GetHash()) &&
!stageEntries.count(cacheEntry)) {
nChildrenToVisit++;
}
}
} else if (!setAllDescendants.count(childEntry)) {
// Schedule for later processing and update our visit count
if (stageEntries.insert(childEntry).second && !setExclude.count(childEntry->GetTx().GetHash())) {
nChildrenToVisit++;
}
}
if (nChildrenToVisit > maxDescendantsToVisit) {
return false;
}
}
}
// setAllDescendants now contains all in-mempool descendants of updateIt.
// Update and add to cached descendant map
int64_t modifySize = 0;
CAmount modifyFee = 0;
int64_t modifyCount = 0;
BOOST_FOREACH(txiter cit, setAllDescendants) {
if (!setExclude.count(cit->GetTx().GetHash())) {
modifySize += cit->GetTxSize();
modifyFee += cit->GetFee();
modifyCount++;
cachedDescendants[updateIt].insert(cit);
}
}
mapTx.modify(updateIt, update_descendant_state(modifySize, modifyFee, modifyCount));
return true;
}
// vHashesToUpdate is the set of transaction hashes from a disconnected block
// which has been re-added to the mempool.
// for each entry, look for descendants that are outside hashesToUpdate, and
// add fee/size information for such descendants to the parent.
void CTxMemPool::UpdateTransactionsFromBlock(const std::vector<uint256> &vHashesToUpdate)
{
LOCK(cs);
// For each entry in vHashesToUpdate, store the set of in-mempool, but not
// in-vHashesToUpdate transactions, so that we don't have to recalculate
// descendants when we come across a previously seen entry.
cacheMap mapMemPoolDescendantsToUpdate;
// Use a set for lookups into vHashesToUpdate (these entries are already
// accounted for in the state of their ancestors)
std::set<uint256> setAlreadyIncluded(vHashesToUpdate.begin(), vHashesToUpdate.end());
// Iterate in reverse, so that whenever we are looking at at a transaction
// we are sure that all in-mempool descendants have already been processed.
// This maximizes the benefit of the descendant cache and guarantees that
// setMemPoolChildren will be updated, an assumption made in
// UpdateForDescendants.
BOOST_REVERSE_FOREACH(const uint256 &hash, vHashesToUpdate) {
// we cache the in-mempool children to avoid duplicate updates
setEntries setChildren;
// calculate children from mapNextTx
txiter it = mapTx.find(hash);
if (it == mapTx.end()) {
continue;
}
std::map<COutPoint, CInPoint>::iterator iter = mapNextTx.lower_bound(COutPoint(hash, 0));
// First calculate the children, and update setMemPoolChildren to
// include them, and update their setMemPoolParents to include this tx.
for (; iter != mapNextTx.end() && iter->first.hash == hash; ++iter) {
const uint256 &childHash = iter->second.ptx->GetHash();
txiter childIter = mapTx.find(childHash);
assert(childIter != mapTx.end());
// We can skip updating entries we've encountered before or that
// are in the block (which are already accounted for).
if (setChildren.insert(childIter).second && !setAlreadyIncluded.count(childHash)) {
UpdateChild(it, childIter, true);
UpdateParent(childIter, it, true);
}
}
if (!UpdateForDescendants(it, 100, mapMemPoolDescendantsToUpdate, setAlreadyIncluded)) {
// Mark as dirty if we can't do the calculation.
mapTx.modify(it, set_dirty());
}
}
}
bool CTxMemPool::CalculateMemPoolAncestors(const CTxMemPoolEntry &entry, setEntries &setAncestors, uint64_t limitAncestorCount, uint64_t limitAncestorSize, uint64_t limitDescendantCount, uint64_t limitDescendantSize, std::string &errString)
{
setEntries parentHashes;
const CTransaction &tx = entry.GetTx();
// Get parents of this transaction that are in the mempool
// Entry may or may not already be in the mempool, and GetMemPoolParents()
// is only valid for entries in the mempool, so we iterate mapTx to find
// parents.
// TODO: optimize this so that we only check limits and walk
// tx.vin when called on entries not already in the mempool.
for (unsigned int i = 0; i < tx.vin.size(); i++) {
txiter piter = mapTx.find(tx.vin[i].prevout.hash);
if (piter != mapTx.end()) {
parentHashes.insert(piter);
if (parentHashes.size() + 1 > limitAncestorCount) {
errString = strprintf("too many unconfirmed parents [limit: %u]", limitAncestorCount);
return false;
}
}
}
size_t totalSizeWithAncestors = entry.GetTxSize();
while (!parentHashes.empty()) {
txiter stageit = *parentHashes.begin();
setAncestors.insert(stageit);
parentHashes.erase(stageit);
totalSizeWithAncestors += stageit->GetTxSize();
if (stageit->GetSizeWithDescendants() + entry.GetTxSize() > limitDescendantSize) {
errString = strprintf("exceeds descendant size limit for tx %s [limit: %u]", stageit->GetTx().GetHash().ToString(), limitDescendantSize);
return false;
} else if (stageit->GetCountWithDescendants() + 1 > limitDescendantCount) {
errString = strprintf("too many descendants for tx %s [limit: %u]", stageit->GetTx().GetHash().ToString(), limitDescendantCount);
return false;
} else if (totalSizeWithAncestors > limitAncestorSize) {
errString = strprintf("exceeds ancestor size limit [limit: %u]", limitAncestorSize);
return false;
}
const setEntries & setMemPoolParents = GetMemPoolParents(stageit);
BOOST_FOREACH(const txiter &phash, setMemPoolParents) {
// If this is a new ancestor, add it.
if (setAncestors.count(phash) == 0) {
parentHashes.insert(phash);
}
if (parentHashes.size() + setAncestors.size() + 1 > limitAncestorCount) {
errString = strprintf("too many unconfirmed ancestors [limit: %u]", limitAncestorCount);
return false;
}
}
}
return true;
}
void CTxMemPool::UpdateAncestorsOf(bool add, txiter it, setEntries &setAncestors)
{
setEntries parentIters = GetMemPoolParents(it);
// add or remove this tx as a child of each parent
BOOST_FOREACH(txiter piter, parentIters) {
UpdateChild(piter, it, add);
}
const int64_t updateCount = (add ? 1 : -1);
const int64_t updateSize = updateCount * it->GetTxSize();
const CAmount updateFee = updateCount * it->GetFee();
BOOST_FOREACH(txiter ancestorIt, setAncestors) {
mapTx.modify(ancestorIt, update_descendant_state(updateSize, updateFee, updateCount));
}
}
void CTxMemPool::UpdateChildrenForRemoval(txiter it)
{
const setEntries &setMemPoolChildren = GetMemPoolChildren(it);
BOOST_FOREACH(txiter updateIt, setMemPoolChildren) {
UpdateParent(updateIt, it, false);
}
}
void CTxMemPool::UpdateForRemoveFromMempool(const setEntries &entriesToRemove)
{
// For each entry, walk back all ancestors and decrement size associated with this
// transaction
const uint64_t nNoLimit = std::numeric_limits<uint64_t>::max();
BOOST_FOREACH(txiter removeIt, entriesToRemove) {
setEntries setAncestors;
const CTxMemPoolEntry &entry = *removeIt;
std::string dummy;
CalculateMemPoolAncestors(entry, setAncestors, nNoLimit, nNoLimit, nNoLimit, nNoLimit, dummy);
// Note that UpdateAncestorsOf severs the child links that point to
// removeIt in the entries for the parents of removeIt. This is
// fine since we don't need to use the mempool children of any entries
// to walk back over our ancestors (but we do need the mempool
// parents!)
UpdateAncestorsOf(false, removeIt, setAncestors);
}
// After updating all the ancestor sizes, we can now sever the link between each
// transaction being removed and any mempool children (ie, update setMemPoolParents
// for each direct child of a transaction being removed).
BOOST_FOREACH(txiter removeIt, entriesToRemove) {
UpdateChildrenForRemoval(removeIt);
}
}
void CTxMemPoolEntry::SetDirty()
{
nCountWithDescendants = 0;
nSizeWithDescendants = nTxSize;
nFeesWithDescendants = nFee;
}
void CTxMemPoolEntry::UpdateState(int64_t modifySize, CAmount modifyFee, int64_t modifyCount)
{
if (!IsDirty()) {
nSizeWithDescendants += modifySize;
assert(int64_t(nSizeWithDescendants) > 0);
nFeesWithDescendants += modifyFee;
assert(nFeesWithDescendants >= 0);
nCountWithDescendants += modifyCount;
assert(int64_t(nCountWithDescendants) > 0);
}
}
CTxMemPool::CTxMemPool(const CFeeRate& _minRelayFee) :
nTransactionsUpdated(0)
{
@ -90,34 +325,103 @@ void CTxMemPool::AddTransactionsUpdated(unsigned int n)
nTransactionsUpdated += n;
}
bool CTxMemPool::addUnchecked(const uint256& hash, const CTxMemPoolEntry &entry, bool fCurrentEstimate)
bool CTxMemPool::addUnchecked(const uint256& hash, const CTxMemPoolEntry &entry, setEntries &setAncestors, bool fCurrentEstimate)
{
// Add to memory pool without checking anything.
// Used by main.cpp AcceptToMemoryPool(), which DOES do
// all the appropriate checks.
LOCK(cs);
mapTx.insert(entry);
const CTransaction& tx = mapTx.find(hash)->GetTx();
for (unsigned int i = 0; i < tx.vin.size(); i++)
indexed_transaction_set::iterator newit = mapTx.insert(entry).first;
mapLinks.insert(make_pair(newit, TxLinks()));
// Update cachedInnerUsage to include contained transaction's usage.
// (When we update the entry for in-mempool parents, memory usage will be
// further updated.)
cachedInnerUsage += entry.DynamicMemoryUsage();
const CTransaction& tx = newit->GetTx();
std::set<uint256> setParentTransactions;
for (unsigned int i = 0; i < tx.vin.size(); i++) {
mapNextTx[tx.vin[i].prevout] = CInPoint(&tx, i);
setParentTransactions.insert(tx.vin[i].prevout.hash);
}
// Don't bother worrying about child transactions of this one.
// Normal case of a new transaction arriving is that there can't be any
// children, because such children would be orphans.
// An exception to that is if a transaction enters that used to be in a block.
// In that case, our disconnect block logic will call UpdateTransactionsFromBlock
// to clean up the mess we're leaving here.
// Update ancestors with information about this tx
BOOST_FOREACH (const uint256 &phash, setParentTransactions) {
txiter pit = mapTx.find(phash);
if (pit != mapTx.end()) {
UpdateParent(newit, pit, true);
}
}
UpdateAncestorsOf(true, newit, setAncestors);
nTransactionsUpdated++;
totalTxSize += entry.GetTxSize();
cachedInnerUsage += entry.DynamicMemoryUsage();
minerPolicyEstimator->processTransaction(entry, fCurrentEstimate);
return true;
}
void CTxMemPool::removeUnchecked(txiter it)
{
const uint256 hash = it->GetTx().GetHash();
BOOST_FOREACH(const CTxIn& txin, it->GetTx().vin)
mapNextTx.erase(txin.prevout);
totalTxSize -= it->GetTxSize();
cachedInnerUsage -= it->DynamicMemoryUsage();
cachedInnerUsage -= memusage::DynamicUsage(mapLinks[it].parents) + memusage::DynamicUsage(mapLinks[it].children);
mapLinks.erase(it);
mapTx.erase(it);
nTransactionsUpdated++;
minerPolicyEstimator->removeTx(hash);
}
// Calculates descendants of entry that are not already in setDescendants, and adds to
// setDescendants. Assumes entryit is already a tx in the mempool and setMemPoolChildren
// is correct for tx and all descendants.
// Also assumes that if an entry is in setDescendants already, then all
// in-mempool descendants of it are already in setDescendants as well, so that we
// can save time by not iterating over those entries.
void CTxMemPool::CalculateDescendants(txiter entryit, setEntries &setDescendants)
{
setEntries stage;
if (setDescendants.count(entryit) == 0) {
stage.insert(entryit);
}
// Traverse down the children of entry, only adding children that are not
// accounted for in setDescendants already (because those children have either
// already been walked, or will be walked in this iteration).
while (!stage.empty()) {
txiter it = *stage.begin();
setDescendants.insert(it);
stage.erase(it);
const setEntries &setChildren = GetMemPoolChildren(it);
BOOST_FOREACH(const txiter &childiter, setChildren) {
if (!setDescendants.count(childiter)) {
stage.insert(childiter);
}
}
}
}
void CTxMemPool::remove(const CTransaction &origTx, std::list<CTransaction>& removed, bool fRecursive)
{
// Remove transaction from memory pool
{
LOCK(cs);
std::deque<uint256> txToRemove;
txToRemove.push_back(origTx.GetHash());
if (fRecursive && !mapTx.count(origTx.GetHash())) {
setEntries txToRemove;
txiter origit = mapTx.find(origTx.GetHash());
if (origit != mapTx.end()) {
txToRemove.insert(origit);
} else if (fRecursive) {
// If recursively removing but origTx isn't in the mempool
// be sure to remove any children that are in the pool. This can
// happen during chain re-orgs if origTx isn't re-accepted into
@ -126,34 +430,23 @@ void CTxMemPool::remove(const CTransaction &origTx, std::list<CTransaction>& rem
std::map<COutPoint, CInPoint>::iterator it = mapNextTx.find(COutPoint(origTx.GetHash(), i));
if (it == mapNextTx.end())
continue;
txToRemove.push_back(it->second.ptx->GetHash());
txiter nextit = mapTx.find(it->second.ptx->GetHash());
assert(nextit != mapTx.end());
txToRemove.insert(nextit);
}
}
while (!txToRemove.empty())
{
uint256 hash = txToRemove.front();
txToRemove.pop_front();
if (!mapTx.count(hash))
continue;
const CTransaction& tx = mapTx.find(hash)->GetTx();
if (fRecursive) {
for (unsigned int i = 0; i < tx.vout.size(); i++) {
std::map<COutPoint, CInPoint>::iterator it = mapNextTx.find(COutPoint(hash, i));
if (it == mapNextTx.end())
continue;
txToRemove.push_back(it->second.ptx->GetHash());
}
setEntries setAllRemoves;
if (fRecursive) {
BOOST_FOREACH(txiter it, txToRemove) {
CalculateDescendants(it, setAllRemoves);
}
BOOST_FOREACH(const CTxIn& txin, tx.vin)
mapNextTx.erase(txin.prevout);
removed.push_back(tx);
totalTxSize -= mapTx.find(hash)->GetTxSize();
cachedInnerUsage -= mapTx.find(hash)->DynamicMemoryUsage();
mapTx.erase(hash);
nTransactionsUpdated++;
minerPolicyEstimator->removeTx(hash);
} else {
setAllRemoves.swap(txToRemove);
}
BOOST_FOREACH(txiter it, setAllRemoves) {
removed.push_back(it->GetTx());
}
RemoveStaged(setAllRemoves);
}
}
@ -229,6 +522,7 @@ void CTxMemPool::removeForBlock(const std::vector<CTransaction>& vtx, unsigned i
void CTxMemPool::clear()
{
LOCK(cs);
mapLinks.clear();
mapTx.clear();
mapNextTx.clear();
totalTxSize = 0;
@ -255,7 +549,12 @@ void CTxMemPool::check(const CCoinsViewCache *pcoins) const
checkTotal += it->GetTxSize();
innerUsage += it->DynamicMemoryUsage();
const CTransaction& tx = it->GetTx();
txlinksMap::const_iterator linksiter = mapLinks.find(it);
assert(linksiter != mapLinks.end());
const TxLinks &links = linksiter->second;
innerUsage += memusage::DynamicUsage(links.parents) + memusage::DynamicUsage(links.children);
bool fDependsWait = false;
setEntries setParentCheck;
BOOST_FOREACH(const CTxIn &txin, tx.vin) {
// Check that every mempool transaction's inputs refer to available coins, or other mempool tx's.
indexed_transaction_set::const_iterator it2 = mapTx.find(txin.prevout.hash);
@ -263,6 +562,7 @@ void CTxMemPool::check(const CCoinsViewCache *pcoins) const
const CTransaction& tx2 = it2->GetTx();
assert(tx2.vout.size() > txin.prevout.n && !tx2.vout[txin.prevout.n].IsNull());
fDependsWait = true;
setParentCheck.insert(it2);
} else {
const CCoins* coins = pcoins->AccessCoins(txin.prevout.hash);
assert(coins && coins->IsAvailable(txin.prevout.n));
@ -274,6 +574,33 @@ void CTxMemPool::check(const CCoinsViewCache *pcoins) const
assert(it3->second.n == i);
i++;
}
assert(setParentCheck == GetMemPoolParents(it));
// Check children against mapNextTx
CTxMemPool::setEntries setChildrenCheck;
std::map<COutPoint, CInPoint>::const_iterator iter = mapNextTx.lower_bound(COutPoint(it->GetTx().GetHash(), 0));
int64_t childSizes = 0;
CAmount childFees = 0;
for (; iter != mapNextTx.end() && iter->first.hash == it->GetTx().GetHash(); ++iter) {
txiter childit = mapTx.find(iter->second.ptx->GetHash());
assert(childit != mapTx.end()); // mapNextTx points to in-mempool transactions
if (setChildrenCheck.insert(childit).second) {
childSizes += childit->GetTxSize();
childFees += childit->GetFee();
}
}
assert(setChildrenCheck == GetMemPoolChildren(it));
// Also check to make sure size/fees is greater than sum with immediate children.
// just a sanity check, not definitive that this calc is correct...
// also check that the size is less than the size of the entire mempool.
if (!it->IsDirty()) {
assert(it->GetSizeWithDescendants() >= childSizes + it->GetTxSize());
assert(it->GetFeesWithDescendants() >= childFees + it->GetFee());
} else {
assert(it->GetSizeWithDescendants() == it->GetTxSize());
assert(it->GetFeesWithDescendants() == it->GetFee());
}
assert(it->GetFeesWithDescendants() >= 0);
if (fDependsWait)
waitingOnDependants.push_back(&(*it));
else {
@ -432,6 +759,60 @@ bool CCoinsViewMemPool::HaveCoins(const uint256 &txid) const {
size_t CTxMemPool::DynamicMemoryUsage() const {
LOCK(cs);
// Estimate the overhead of mapTx to be 6 pointers + an allocation, as no exact formula for boost::multi_index_contained is implemented.
return memusage::MallocUsage(sizeof(CTxMemPoolEntry) + 6 * sizeof(void*)) * mapTx.size() + memusage::DynamicUsage(mapNextTx) + memusage::DynamicUsage(mapDeltas) + cachedInnerUsage;
// Estimate the overhead of mapTx to be 9 pointers + an allocation, as no exact formula for boost::multi_index_contained is implemented.
return memusage::MallocUsage(sizeof(CTxMemPoolEntry) + 9 * sizeof(void*)) * mapTx.size() + memusage::DynamicUsage(mapNextTx) + memusage::DynamicUsage(mapDeltas) + memusage::DynamicUsage(mapLinks) + cachedInnerUsage;
}
void CTxMemPool::RemoveStaged(setEntries &stage) {
AssertLockHeld(cs);
UpdateForRemoveFromMempool(stage);
BOOST_FOREACH(const txiter& it, stage) {
removeUnchecked(it);
}
}
bool CTxMemPool::addUnchecked(const uint256&hash, const CTxMemPoolEntry &entry, bool fCurrentEstimate)
{
LOCK(cs);
setEntries setAncestors;
uint64_t nNoLimit = std::numeric_limits<uint64_t>::max();
std::string dummy;
CalculateMemPoolAncestors(entry, setAncestors, nNoLimit, nNoLimit, nNoLimit, nNoLimit, dummy);
return addUnchecked(hash, entry, setAncestors, fCurrentEstimate);
}
void CTxMemPool::UpdateChild(txiter entry, txiter child, bool add)
{
setEntries s;
if (add && mapLinks[entry].children.insert(child).second) {
cachedInnerUsage += memusage::IncrementalDynamicUsage(s);
} else if (!add && mapLinks[entry].children.erase(child)) {
cachedInnerUsage -= memusage::IncrementalDynamicUsage(s);
}
}
void CTxMemPool::UpdateParent(txiter entry, txiter parent, bool add)
{
setEntries s;
if (add && mapLinks[entry].parents.insert(parent).second) {
cachedInnerUsage += memusage::IncrementalDynamicUsage(s);
} else if (!add && mapLinks[entry].parents.erase(parent)) {
cachedInnerUsage -= memusage::IncrementalDynamicUsage(s);
}
}
const CTxMemPool::setEntries & CTxMemPool::GetMemPoolParents(txiter entry) const
{
assert (entry != mapTx.end());
txlinksMap::const_iterator it = mapLinks.find(entry);
assert(it != mapLinks.end());
return it->second.parents;
}
const CTxMemPool::setEntries & CTxMemPool::GetMemPoolChildren(txiter entry) const
{
assert (entry != mapTx.end());
txlinksMap::const_iterator it = mapLinks.find(entry);
assert(it != mapLinks.end());
return it->second.children;
}

View file

@ -7,6 +7,7 @@
#define BITCOIN_TXMEMPOOL_H
#include <list>
#include <set>
#include "amount.h"
#include "coins.h"
@ -34,9 +35,25 @@ inline bool AllowFree(double dPriority)
/** Fake height value used in CCoins to signify they are only in the memory pool (since 0.8) */
static const unsigned int MEMPOOL_HEIGHT = 0x7FFFFFFF;
/**
* CTxMemPool stores these:
class CTxMemPool;
/** \class CTxMemPoolEntry
*
* CTxMemPoolEntry stores data about the correponding transaction, as well
* as data about all in-mempool transactions that depend on the transaction
* ("descendant" transactions).
*
* When a new entry is added to the mempool, we update the descendant state
* (nCountWithDescendants, nSizeWithDescendants, and nFeesWithDescendants) for
* all ancestors of the newly added transaction.
*
* If updating the descendant state is skipped, we can mark the entry as
* "dirty", and set nSizeWithDescendants/nFeesWithDescendants to equal nTxSize/
* nTxFee. (This can potentially happen during a reorg, where we limit the
* amount of work we're willing to do to avoid consuming too much CPU.)
*
*/
class CTxMemPoolEntry
{
private:
@ -45,27 +62,69 @@ private:
size_t nTxSize; //! ... and avoid recomputing tx size
size_t nModSize; //! ... and modified size for priority
size_t nUsageSize; //! ... and total memory usage
CFeeRate feeRate; //! ... and fee per kB
int64_t nTime; //! Local time when entering the mempool
double dPriority; //! Priority when entering the mempool
unsigned int nHeight; //! Chain height when entering the mempool
bool hadNoDependencies; //! Not dependent on any other txs when it entered the mempool
// Information about descendants of this transaction that are in the
// mempool; if we remove this transaction we must remove all of these
// descendants as well. if nCountWithDescendants is 0, treat this entry as
// dirty, and nSizeWithDescendants and nFeesWithDescendants will not be
// correct.
uint64_t nCountWithDescendants; //! number of descendant transactions
uint64_t nSizeWithDescendants; //! ... and size
CAmount nFeesWithDescendants; //! ... and total fees (all including us)
public:
CTxMemPoolEntry(const CTransaction& _tx, const CAmount& _nFee,
int64_t _nTime, double _dPriority, unsigned int _nHeight, bool poolHasNoInputsOf = false);
CTxMemPoolEntry();
CTxMemPoolEntry(const CTxMemPoolEntry& other);
const CTransaction& GetTx() const { return this->tx; }
double GetPriority(unsigned int currentHeight) const;
CAmount GetFee() const { return nFee; }
CFeeRate GetFeeRate() const { return feeRate; }
size_t GetTxSize() const { return nTxSize; }
int64_t GetTime() const { return nTime; }
unsigned int GetHeight() const { return nHeight; }
bool WasClearAtEntry() const { return hadNoDependencies; }
size_t DynamicMemoryUsage() const { return nUsageSize; }
// Adjusts the descendant state, if this entry is not dirty.
void UpdateState(int64_t modifySize, CAmount modifyFee, int64_t modifyCount);
/** We can set the entry to be dirty if doing the full calculation of in-
* mempool descendants will be too expensive, which can potentially happen
* when re-adding transactions from a block back to the mempool.
*/
void SetDirty();
bool IsDirty() const { return nCountWithDescendants == 0; }
uint64_t GetCountWithDescendants() const { return nCountWithDescendants; }
uint64_t GetSizeWithDescendants() const { return nSizeWithDescendants; }
CAmount GetFeesWithDescendants() const { return nFeesWithDescendants; }
};
// Helpers for modifying CTxMemPool::mapTx, which is a boost multi_index.
struct update_descendant_state
{
update_descendant_state(int64_t _modifySize, CAmount _modifyFee, int64_t _modifyCount) :
modifySize(_modifySize), modifyFee(_modifyFee), modifyCount(_modifyCount)
{}
void operator() (CTxMemPoolEntry &e)
{ e.UpdateState(modifySize, modifyFee, modifyCount); }
private:
int64_t modifySize;
CAmount modifyFee;
int64_t modifyCount;
};
struct set_dirty
{
void operator() (CTxMemPoolEntry &e)
{ e.SetDirty(); }
};
// extracts a TxMemPoolEntry's transaction hash
@ -78,14 +137,49 @@ struct mempoolentry_txid
}
};
/** \class CompareTxMemPoolEntryByFee
*
* Sort an entry by max(feerate of entry's tx, feerate with all descendants).
*/
class CompareTxMemPoolEntryByFee
{
public:
bool operator()(const CTxMemPoolEntry& a, const CTxMemPoolEntry& b)
{
if (a.GetFeeRate() == b.GetFeeRate())
bool fUseADescendants = UseDescendantFeeRate(a);
bool fUseBDescendants = UseDescendantFeeRate(b);
double aFees = fUseADescendants ? a.GetFeesWithDescendants() : a.GetFee();
double aSize = fUseADescendants ? a.GetSizeWithDescendants() : a.GetTxSize();
double bFees = fUseBDescendants ? b.GetFeesWithDescendants() : b.GetFee();
double bSize = fUseBDescendants ? b.GetSizeWithDescendants() : b.GetTxSize();
// Avoid division by rewriting (a/b > c/d) as (a*d > c*b).
double f1 = aFees * bSize;
double f2 = aSize * bFees;
if (f1 == f2) {
return a.GetTime() < b.GetTime();
return a.GetFeeRate() > b.GetFeeRate();
}
return f1 > f2;
}
// Calculate which feerate to use for an entry (avoiding division).
bool UseDescendantFeeRate(const CTxMemPoolEntry &a)
{
double f1 = (double)a.GetFee() * a.GetSizeWithDescendants();
double f2 = (double)a.GetFeesWithDescendants() * a.GetTxSize();
return f2 > f1;
}
};
class CompareTxMemPoolEntryByEntryTime
{
public:
bool operator()(const CTxMemPoolEntry& a, const CTxMemPoolEntry& b)
{
return a.GetTime() < b.GetTime();
}
};
@ -114,6 +208,71 @@ public:
* are added to the pool: if a new transaction double-spends
* an input of a transaction in the pool, it is dropped,
* as are non-standard transactions.
*
* CTxMemPool::mapTx, and CTxMemPoolEntry bookkeeping:
*
* mapTx is a boost::multi_index that sorts the mempool on 2 criteria:
* - transaction hash
* - feerate [we use max(feerate of tx, feerate of tx with all descendants)]
*
* 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.
*
* Adding transactions from a disconnected block can be very time consuming,
* because we don't have a way to limit the number of in-mempool descendants.
* To bound CPU processing, we limit the amount of work we're willing to do
* to properly update the descendant information for a tx being added from
* a disconnected block. If we would exceed the limit, then we instead mark
* the entry as "dirty", and set the feerate for sorting purposes to be equal
* the feerate of the transaction without any descendants.
*
*/
class CTxMemPool
{
@ -141,6 +300,31 @@ public:
mutable CCriticalSection cs;
indexed_transaction_set mapTx;
typedef indexed_transaction_set::nth_index<0>::type::iterator txiter;
struct CompareIteratorByHash {
bool operator()(const txiter &a, const txiter &b) const {
return a->GetTx().GetHash() < b->GetTx().GetHash();
}
};
typedef std::set<txiter, CompareIteratorByHash> setEntries;
private:
typedef std::map<txiter, setEntries, CompareIteratorByHash> cacheMap;
struct TxLinks {
setEntries parents;
setEntries children;
};
typedef std::map<txiter, TxLinks, CompareIteratorByHash> txlinksMap;
txlinksMap mapLinks;
const setEntries & GetMemPoolParents(txiter entry) const;
const setEntries & GetMemPoolChildren(txiter entry) const;
void UpdateParent(txiter entry, txiter parent, bool add);
void UpdateChild(txiter entry, txiter child, bool add);
public:
std::map<COutPoint, CInPoint> mapNextTx;
std::map<uint256, std::pair<double, CAmount> > mapDeltas;
@ -156,7 +340,13 @@ public:
void check(const CCoinsViewCache *pcoins) const;
void setSanityCheck(bool _fSanityCheck) { fSanityCheck = _fSanityCheck; }
// addUnchecked must updated state for all ancestors of a given transaction,
// to track size/count of descendant transactions. First version of
// addUnchecked can be used to have it call CalculateMemPoolAncestors(), and
// then invoke the second version.
bool addUnchecked(const uint256& hash, const CTxMemPoolEntry &entry, bool fCurrentEstimate = true);
bool addUnchecked(const uint256& hash, const CTxMemPoolEntry &entry, setEntries &setAncestors, bool fCurrentEstimate = true);
void remove(const CTransaction &tx, std::list<CTransaction>& removed, bool fRecursive = false);
void removeCoinbaseSpends(const CCoinsViewCache *pcoins, unsigned int nMemPoolHeight);
void removeConflicts(const CTransaction &tx, std::list<CTransaction>& removed);
@ -178,6 +368,33 @@ public:
void ApplyDeltas(const uint256 hash, double &dPriorityDelta, CAmount &nFeeDelta);
void ClearPrioritisation(const uint256 hash);
public:
/** 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.*/
void RemoveStaged(setEntries &stage);
/** 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).
* UpdateTransactionsFromBlock() will find child transactions and update the
* descendant state for each transaction in hashesToUpdate (excluding any
* child transactions present in hashesToUpdate, which are already accounted
* for). Note: hashesToUpdate should be the set of transactions from the
* disconnected block that have been accepted back into the mempool.
*/
void UpdateTransactionsFromBlock(const std::vector<uint256> &hashesToUpdate);
/** 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
*/
bool CalculateMemPoolAncestors(const CTxMemPoolEntry &entry, setEntries &setAncestors, uint64_t limitAncestorCount, uint64_t limitAncestorSize, uint64_t limitDescendantCount, uint64_t limitDescendantSize, std::string &errString);
unsigned long size()
{
LOCK(cs);
@ -209,6 +426,48 @@ public:
bool ReadFeeEstimates(CAutoFile& filein);
size_t DynamicMemoryUsage() const;
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. setExclude is 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).
*
* If updating an entry requires looking at more than maxDescendantsToVisit
* transactions, outside of the ones in setExclude, then give up.
*
* cachedDescendants 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.
*/
bool UpdateForDescendants(txiter updateIt,
int maxDescendantsToVisit,
cacheMap &cachedDescendants,
const std::set<uint256> &setExclude);
/** Update ancestors of hash to add/remove it as a descendant transaction. */
void UpdateAncestorsOf(bool add, txiter hash, setEntries &setAncestors);
/** For each transaction being removed, update ancestors and any direct children. */
void UpdateForRemoveFromMempool(const setEntries &entriesToRemove);
/** Sever link between specified transaction and direct children. */
void UpdateChildrenForRemoval(txiter entry);
/** Populate setDescendants with all in-mempool descendants of hash.
* Assumes that setDescendants includes all in-mempool descendants of anything
* already in it. */
void CalculateDescendants(txiter it, setEntries &setDescendants);
/** 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.
*/
void removeUnchecked(txiter entry);
};
/**