1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
|
// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2016 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#ifndef BITCOIN_TXMEMPOOL_H
#define BITCOIN_TXMEMPOOL_H
#include <memory>
#include <set>
#include <map>
#include <vector>
#include <utility>
#include <string>
#include "amount.h"
#include "coins.h"
#include "indirectmap.h"
#include "primitives/transaction.h"
#include "sync.h"
#include "random.h"
#include "boost/multi_index_container.hpp"
#include "boost/multi_index/ordered_index.hpp"
#include "boost/multi_index/hashed_index.hpp"
#include <boost/signals2/signal.hpp>
class CAutoFile;
class CBlockIndex;
inline double AllowFreeThreshold()
{
return COIN * 144 / 250;
}
inline bool AllowFree(double dPriority)
{
// Large (in bytes) low-priority (new, small-coin) transactions
// need a fee.
return dPriority > AllowFreeThreshold();
}
/** 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;
struct LockPoints
{
// Will be set to the blockchain height and median time past
// values that would be necessary to satisfy all relative locktime
// constraints (BIP68) of this tx given our view of block chain history
int height;
int64_t time;
// As long as the current chain descends from the highest height block
// containing one of the inputs used in the calculation, then the cached
// values are still valid even after a reorg.
CBlockIndex* maxInputBlock;
LockPoints() : height(0), time(0), maxInputBlock(NULL) { }
};
class CTxMemPool;
/** \class CTxMemPoolEntry
*
* CTxMemPoolEntry stores data about the corresponding 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 nModFeesWithDescendants) 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/nModFeesWithDescendants to equal nTxSize/
* nFee+feeDelta. (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:
CTransactionRef tx;
CAmount nFee; //!< Cached to avoid expensive parent-transaction lookups
size_t nTxWeight; //!< ... and avoid recomputing tx weight (also used for GetTxSize())
size_t nModSize; //!< ... and modified size for priority
size_t nUsageSize; //!< ... and total memory usage
int64_t nTime; //!< Local time when entering the mempool
double entryPriority; //!< Priority when entering the mempool
unsigned int entryHeight; //!< Chain height when entering the mempool
CAmount inChainInputValue; //!< Sum of all txin values that are already in blockchain
bool spendsCoinbase; //!< keep track of transactions that spend a coinbase
int64_t sigOpCost; //!< Total sigop cost
int64_t feeDelta; //!< Used for determining the priority of the transaction for mining in a block
LockPoints lockPoints; //!< Track the height and time at which tx was final
// 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 nModFeesWithDescendants will not be
// correct.
uint64_t nCountWithDescendants; //!< number of descendant transactions
uint64_t nSizeWithDescendants; //!< ... and size
CAmount nModFeesWithDescendants; //!< ... and total fees (all including us)
// Analogous statistics for ancestor transactions
uint64_t nCountWithAncestors;
uint64_t nSizeWithAncestors;
CAmount nModFeesWithAncestors;
int64_t nSigOpCostWithAncestors;
public:
CTxMemPoolEntry(const CTransactionRef& _tx, const CAmount& _nFee,
int64_t _nTime, double _entryPriority, unsigned int _entryHeight,
CAmount _inChainInputValue, bool spendsCoinbase,
int64_t nSigOpsCost, LockPoints lp);
CTxMemPoolEntry(const CTxMemPoolEntry& other);
const CTransaction& GetTx() const { return *this->tx; }
CTransactionRef GetSharedTx() const { return this->tx; }
/**
* Fast calculation of lower bound of current priority as update
* from entry priority. Only inputs that were originally in-chain will age.
*/
double GetPriority(unsigned int currentHeight) const;
const CAmount& GetFee() const { return nFee; }
size_t GetTxSize() const;
size_t GetTxWeight() const { return nTxWeight; }
int64_t GetTime() const { return nTime; }
unsigned int GetHeight() const { return entryHeight; }
int64_t GetSigOpCost() const { return sigOpCost; }
int64_t GetModifiedFee() const { return nFee + feeDelta; }
size_t DynamicMemoryUsage() const { return nUsageSize; }
const LockPoints& GetLockPoints() const { return lockPoints; }
// Adjusts the descendant state, if this entry is not dirty.
void UpdateDescendantState(int64_t modifySize, CAmount modifyFee, int64_t modifyCount);
// Adjusts the ancestor state
void UpdateAncestorState(int64_t modifySize, CAmount modifyFee, int64_t modifyCount, int modifySigOps);
// Updates the fee delta used for mining priority score, and the
// modified fees with descendants.
void UpdateFeeDelta(int64_t feeDelta);
// Update the LockPoints after a reorg
void UpdateLockPoints(const LockPoints& lp);
uint64_t GetCountWithDescendants() const { return nCountWithDescendants; }
uint64_t GetSizeWithDescendants() const { return nSizeWithDescendants; }
CAmount GetModFeesWithDescendants() const { return nModFeesWithDescendants; }
bool GetSpendsCoinbase() const { return spendsCoinbase; }
uint64_t GetCountWithAncestors() const { return nCountWithAncestors; }
uint64_t GetSizeWithAncestors() const { return nSizeWithAncestors; }
CAmount GetModFeesWithAncestors() const { return nModFeesWithAncestors; }
int64_t GetSigOpCostWithAncestors() const { return nSigOpCostWithAncestors; }
mutable size_t vTxHashesIdx; //!< Index in mempool's vTxHashes
};
// 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.UpdateDescendantState(modifySize, modifyFee, modifyCount); }
private:
int64_t modifySize;
CAmount modifyFee;
int64_t modifyCount;
};
struct update_ancestor_state
{
update_ancestor_state(int64_t _modifySize, CAmount _modifyFee, int64_t _modifyCount, int64_t _modifySigOpsCost) :
modifySize(_modifySize), modifyFee(_modifyFee), modifyCount(_modifyCount), modifySigOpsCost(_modifySigOpsCost)
{}
void operator() (CTxMemPoolEntry &e)
{ e.UpdateAncestorState(modifySize, modifyFee, modifyCount, modifySigOpsCost); }
private:
int64_t modifySize;
CAmount modifyFee;
int64_t modifyCount;
int64_t modifySigOpsCost;
};
struct update_fee_delta
{
update_fee_delta(int64_t _feeDelta) : feeDelta(_feeDelta) { }
void operator() (CTxMemPoolEntry &e) { e.UpdateFeeDelta(feeDelta); }
private:
int64_t feeDelta;
};
struct update_lock_points
{
update_lock_points(const LockPoints& _lp) : lp(_lp) { }
void operator() (CTxMemPoolEntry &e) { e.UpdateLockPoints(lp); }
private:
const LockPoints& lp;
};
// extracts a TxMemPoolEntry's transaction hash
struct mempoolentry_txid
{
typedef uint256 result_type;
result_type operator() (const CTxMemPoolEntry &entry) const
{
return entry.GetTx().GetHash();
}
};
/** \class CompareTxMemPoolEntryByDescendantScore
*
* Sort an entry by max(score/size of entry's tx, score/size with all descendants).
*/
class CompareTxMemPoolEntryByDescendantScore
{
public:
bool operator()(const CTxMemPoolEntry& a, const CTxMemPoolEntry& b)
{
bool fUseADescendants = UseDescendantScore(a);
bool fUseBDescendants = UseDescendantScore(b);
double aModFee = fUseADescendants ? a.GetModFeesWithDescendants() : a.GetModifiedFee();
double aSize = fUseADescendants ? a.GetSizeWithDescendants() : a.GetTxSize();
double bModFee = fUseBDescendants ? b.GetModFeesWithDescendants() : b.GetModifiedFee();
double bSize = fUseBDescendants ? b.GetSizeWithDescendants() : b.GetTxSize();
// Avoid division by rewriting (a/b > c/d) as (a*d > c*b).
double f1 = aModFee * bSize;
double f2 = aSize * bModFee;
if (f1 == f2) {
return a.GetTime() >= b.GetTime();
}
return f1 < f2;
}
// Calculate which score to use for an entry (avoiding division).
bool UseDescendantScore(const CTxMemPoolEntry &a)
{
double f1 = (double)a.GetModifiedFee() * a.GetSizeWithDescendants();
double f2 = (double)a.GetModFeesWithDescendants() * a.GetTxSize();
return f2 > f1;
}
};
/** \class CompareTxMemPoolEntryByScore
*
* Sort by score of entry ((fee+delta)/size) in descending order
*/
class CompareTxMemPoolEntryByScore
{
public:
bool operator()(const CTxMemPoolEntry& a, const CTxMemPoolEntry& b)
{
double f1 = (double)a.GetModifiedFee() * b.GetTxSize();
double f2 = (double)b.GetModifiedFee() * a.GetTxSize();
if (f1 == f2) {
return b.GetTx().GetHash() < a.GetTx().GetHash();
}
return f1 > f2;
}
};
class CompareTxMemPoolEntryByEntryTime
{
public:
bool operator()(const CTxMemPoolEntry& a, const CTxMemPoolEntry& b)
{
return a.GetTime() < b.GetTime();
}
};
class CompareTxMemPoolEntryByAncestorFee
{
public:
bool operator()(const CTxMemPoolEntry& a, const CTxMemPoolEntry& b)
{
double aFees = a.GetModFeesWithAncestors();
double aSize = a.GetSizeWithAncestors();
double bFees = b.GetModFeesWithAncestors();
double bSize = b.GetSizeWithAncestors();
// 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.GetTx().GetHash() < b.GetTx().GetHash();
}
return f1 > f2;
}
};
// Multi_index tag names
struct descendant_score {};
struct entry_time {};
struct mining_score {};
struct ancestor_score {};
class CBlockPolicyEstimator;
/**
* Information about a mempool transaction.
*/
struct TxMempoolInfo
{
/** The transaction itself */
CTransactionRef tx;
/** Time the transaction entered the mempool. */
int64_t nTime;
/** Feerate of the transaction. */
CFeeRate feeRate;
/** The fee delta. */
int64_t nFeeDelta;
};
/** Reason why a transaction was removed from the mempool,
* this is passed to the notification signal.
*/
enum class MemPoolRemovalReason {
UNKNOWN = 0, //! Manually removed or unknown reason
EXPIRY, //! Expired from mempool
SIZELIMIT, //! Removed in size limiting
REORG, //! Removed for reorganization
BLOCK, //! Removed for block
CONFLICT, //! Removed for conflict with in-block transaction
REPLACED //! Removed for replacement
};
/**
* 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 4 criteria:
* - transaction hash
* - feerate [we use max(feerate of tx, feerate of tx with all descendants)]
* - time in mempool
* - mining score (feerate modified by any fee deltas from PrioritiseTransaction)
*
* 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
{
private:
uint32_t nCheckFrequency; //!< Value n means that n times in 2^32 we check.
unsigned int nTransactionsUpdated;
CBlockPolicyEstimator* minerPolicyEstimator;
uint64_t totalTxSize; //!< sum of all mempool tx's virtual sizes. Differs from serialized tx size since witness data is discounted. Defined in BIP 141.
uint64_t cachedInnerUsage; //!< sum of dynamic memory usage of all the map elements (NOT the maps themselves)
mutable int64_t lastRollingFeeUpdate;
mutable bool blockSinceLastRollingFeeBump;
mutable double rollingMinimumFeeRate; //!< minimum fee to get into the pool, decreases exponentially
void trackPackageRemoved(const CFeeRate& rate);
public:
static const int ROLLING_FEE_HALFLIFE = 60 * 60 * 12; // public only for testing
typedef boost::multi_index_container<
CTxMemPoolEntry,
boost::multi_index::indexed_by<
// sorted by txid
boost::multi_index::hashed_unique<mempoolentry_txid, SaltedTxidHasher>,
// sorted by fee rate
boost::multi_index::ordered_non_unique<
boost::multi_index::tag<descendant_score>,
boost::multi_index::identity<CTxMemPoolEntry>,
CompareTxMemPoolEntryByDescendantScore
>,
// sorted by entry time
boost::multi_index::ordered_non_unique<
boost::multi_index::tag<entry_time>,
boost::multi_index::identity<CTxMemPoolEntry>,
CompareTxMemPoolEntryByEntryTime
>,
// sorted by score (for mining prioritization)
boost::multi_index::ordered_unique<
boost::multi_index::tag<mining_score>,
boost::multi_index::identity<CTxMemPoolEntry>,
CompareTxMemPoolEntryByScore
>,
// sorted by fee rate with ancestors
boost::multi_index::ordered_non_unique<
boost::multi_index::tag<ancestor_score>,
boost::multi_index::identity<CTxMemPoolEntry>,
CompareTxMemPoolEntryByAncestorFee
>
>
> indexed_transaction_set;
mutable CCriticalSection cs;
indexed_transaction_set mapTx;
typedef indexed_transaction_set::nth_index<0>::type::iterator txiter;
std::vector<std::pair<uint256, txiter> > vTxHashes; //!< All tx witness hashes/entries in mapTx, in random order
struct CompareIteratorByHash {
bool operator()(const txiter &a, const txiter &b) const {
return a->GetTx().GetHash() < b->GetTx().GetHash();
}
};
typedef std::set<txiter, CompareIteratorByHash> setEntries;
const setEntries & GetMemPoolParents(txiter entry) const;
const setEntries & GetMemPoolChildren(txiter entry) const;
private:
typedef std::map<txiter, setEntries, CompareIteratorByHash> cacheMap;
struct TxLinks {
setEntries parents;
setEntries children;
};
typedef std::map<txiter, TxLinks, CompareIteratorByHash> txlinksMap;
txlinksMap mapLinks;
void UpdateParent(txiter entry, txiter parent, bool add);
void UpdateChild(txiter entry, txiter child, bool add);
std::vector<indexed_transaction_set::const_iterator> GetSortedDepthAndScore() const;
public:
indirectmap<COutPoint, const CTransaction*> mapNextTx;
std::map<uint256, std::pair<double, CAmount> > mapDeltas;
/** Create a new CTxMemPool.
*/
CTxMemPool(const CFeeRate& _minReasonableRelayFee);
~CTxMemPool();
/**
* 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.
*/
void check(const CCoinsViewCache *pcoins) const;
void setSanityCheck(double dFrequency = 1.0) { nCheckFrequency = dFrequency * 4294967295.0; }
// 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 validFeeEstimate = true);
bool addUnchecked(const uint256& hash, const CTxMemPoolEntry &entry, setEntries &setAncestors, bool validFeeEstimate = true);
void removeRecursive(const CTransaction &tx, MemPoolRemovalReason reason = MemPoolRemovalReason::UNKNOWN);
void removeForReorg(const CCoinsViewCache *pcoins, unsigned int nMemPoolHeight, int flags);
void removeConflicts(const CTransaction &tx);
void removeForBlock(const std::vector<CTransactionRef>& vtx, unsigned int nBlockHeight);
void clear();
void _clear(); //lock free
bool CompareDepthAndScore(const uint256& hasha, const uint256& hashb);
void queryHashes(std::vector<uint256>& vtxid);
void pruneSpent(const uint256& hash, CCoins &coins);
unsigned int GetTransactionsUpdated() const;
void AddTransactionsUpdated(unsigned int n);
/**
* 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.
*/
bool HasNoInputsOf(const CTransaction& tx) const;
/** Affect CreateNewBlock prioritisation of transactions */
void PrioritiseTransaction(const uint256 hash, const std::string strHash, double dPriorityDelta, const CAmount& nFeeDelta);
void ApplyDeltas(const uint256 hash, double &dPriorityDelta, CAmount &nFeeDelta) const;
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, 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.
*/
void RemoveStaged(setEntries &stage, bool updateDescendants, MemPoolRemovalReason reason = MemPoolRemovalReason::UNKNOWN);
/** 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
* 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
*/
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;
/** 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);
/** 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.
*/
CFeeRate GetMinFee(size_t sizelimit) const;
/** Remove transactions from the mempool until its dynamic size is <= sizelimit.
* pvNoSpendsRemaining, if set, will be populated with the list of transactions
* which are not in mempool which no longer have any spends in this mempool.
*/
void TrimToSize(size_t sizelimit, std::vector<uint256>* pvNoSpendsRemaining=NULL);
/** Expire all transaction (and their dependencies) in the mempool older than time. Return the number of removed transactions. */
int Expire(int64_t time);
/** Returns false if the transaction is in the mempool and not within the chain limit specified. */
bool TransactionWithinChainLimit(const uint256& txid, size_t chainLimit) const;
unsigned long size()
{
LOCK(cs);
return mapTx.size();
}
uint64_t GetTotalTxSize()
{
LOCK(cs);
return totalTxSize;
}
bool exists(uint256 hash) const
{
LOCK(cs);
return (mapTx.count(hash) != 0);
}
CTransactionRef get(const uint256& hash) const;
TxMempoolInfo info(const uint256& hash) const;
std::vector<TxMempoolInfo> infoAll() const;
/** Estimate fee rate needed to get into the next nBlocks
* If no answer can be given at nBlocks, return an estimate
* at the lowest number of blocks where one can be given
*/
CFeeRate estimateSmartFee(int nBlocks, int *answerFoundAtBlocks = NULL) const;
/** Estimate fee rate needed to get into the next nBlocks */
CFeeRate estimateFee(int nBlocks) const;
/** Estimate priority needed to get into the next nBlocks
* If no answer can be given at nBlocks, return an estimate
* at the lowest number of blocks where one can be given
*/
double estimateSmartPriority(int nBlocks, int *answerFoundAtBlocks = NULL) const;
/** Estimate priority needed to get into the next nBlocks */
double estimatePriority(int nBlocks) const;
/** Write/Read estimates to disk */
bool WriteFeeEstimates(CAutoFile& fileout) const;
bool ReadFeeEstimates(CAutoFile& filein);
size_t DynamicMemoryUsage() const;
boost::signals2::signal<void (CTransactionRef)> NotifyEntryAdded;
boost::signals2::signal<void (CTransactionRef, MemPoolRemovalReason)> NotifyEntryRemoved;
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).
*
* 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.
*/
void UpdateForDescendants(txiter updateIt,
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);
/** Set ancestor state for an entry */
void UpdateEntryForAncestors(txiter it, const setEntries &setAncestors);
/** For each transaction being removed, update ancestors and any direct children.
* If updateDescendants is true, then also update in-mempool descendants'
* ancestor state. */
void UpdateForRemoveFromMempool(const setEntries &entriesToRemove, bool updateDescendants);
/** Sever link between specified transaction and direct children. */
void UpdateChildrenForRemoval(txiter entry);
/** 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, MemPoolRemovalReason reason = MemPoolRemovalReason::UNKNOWN);
};
/**
* CCoinsView that brings transactions from a memorypool into view.
* It does not check for spendings by memory pool transactions.
*/
class CCoinsViewMemPool : public CCoinsViewBacked
{
protected:
const CTxMemPool& mempool;
public:
CCoinsViewMemPool(CCoinsView* baseIn, const CTxMemPool& mempoolIn);
bool GetCoins(const uint256 &txid, CCoins &coins) const;
bool HaveCoins(const uint256 &txid) const;
};
// We want to sort transactions by coin age priority
typedef std::pair<double, CTxMemPool::txiter> TxCoinAgePriority;
struct TxCoinAgePriorityCompare
{
bool operator()(const TxCoinAgePriority& a, const TxCoinAgePriority& b)
{
if (a.first == b.first)
return CompareTxMemPoolEntryByScore()(*(b.second), *(a.second)); //Reverse order to make sort less than
return a.first < b.first;
}
};
#endif // BITCOIN_TXMEMPOOL_H
|