src/test/mempool_tests.cpp

   1 // Copyright (c) 2011-2016 The Bitcoin Core developers
   2 // Distributed under the MIT software license, see the accompanying
   3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
   4
   5 #include "policy/policy.h"
   6 #include "txmempool.h"
   7 #include "util.h"
   8
   9 #include "test/test_bitcoin.h"
  10
  11 #include <boost/test/unit_test.hpp>
  12 #include <list>
  13 #include <vector>
  14
  15 BOOST_FIXTURE_TEST_SUITE(mempool_tests, TestingSetup)
  16
  17 BOOST_AUTO_TEST_CASE(MempoolRemoveTest)
  18 {
  19     // Test CTxMemPool::remove functionality
  20
  21     TestMemPoolEntryHelper entry;
  22     // Parent transaction with three children,
  23     // and three grand-children:
  24     CMutableTransaction txParent;
  25     txParent.vin.resize(1);
  26     txParent.vin[0].scriptSig = CScript() << OP_11;
  27     txParent.vout.resize(3);
  28     for (int i = 0; i < 3; i++)
  29     {
  30         txParent.vout[i].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
  31         txParent.vout[i].nValue = 33000LL;
  32     }
  33     CMutableTransaction txChild[3];
  34     for (int i = 0; i < 3; i++)
  35     {
  36         txChild[i].vin.resize(1);
  37         txChild[i].vin[0].scriptSig = CScript() << OP_11;
  38         txChild[i].vin[0].prevout.hash = txParent.GetHash();
  39         txChild[i].vin[0].prevout.n = i;
  40         txChild[i].vout.resize(1);
  41         txChild[i].vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
  42         txChild[i].vout[0].nValue = 11000LL;
  43     }
  44     CMutableTransaction txGrandChild[3];
  45     for (int i = 0; i < 3; i++)
  46     {
  47         txGrandChild[i].vin.resize(1);
  48         txGrandChild[i].vin[0].scriptSig = CScript() << OP_11;
  49         txGrandChild[i].vin[0].prevout.hash = txChild[i].GetHash();
  50         txGrandChild[i].vin[0].prevout.n = 0;
  51         txGrandChild[i].vout.resize(1);
  52         txGrandChild[i].vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
  53         txGrandChild[i].vout[0].nValue = 11000LL;
  54     }
  55
  56
  57     CTxMemPool testPool;
  58
  59     // Nothing in pool, remove should do nothing:
  60     unsigned int poolSize = testPool.size();
  61     testPool.removeRecursive(txParent);
  62     BOOST_CHECK_EQUAL(testPool.size(), poolSize);
  63
  64     // Just the parent:
  65     testPool.addUnchecked(txParent.GetHash(), entry.FromTx(txParent));
  66     poolSize = testPool.size();
  67     testPool.removeRecursive(txParent);
  68     BOOST_CHECK_EQUAL(testPool.size(), poolSize - 1);
  69
  70     // Parent, children, grandchildren:
  71     testPool.addUnchecked(txParent.GetHash(), entry.FromTx(txParent));
  72     for (int i = 0; i < 3; i++)
  73     {
  74         testPool.addUnchecked(txChild[i].GetHash(), entry.FromTx(txChild[i]));
  75         testPool.addUnchecked(txGrandChild[i].GetHash(), entry.FromTx(txGrandChild[i]));
  76     }
  77     // Remove Child[0], GrandChild[0] should be removed:
  78     poolSize = testPool.size();
  79     testPool.removeRecursive(txChild[0]);
  80     BOOST_CHECK_EQUAL(testPool.size(), poolSize - 2);
  81     // ... make sure grandchild and child are gone:
  82     poolSize = testPool.size();
  83     testPool.removeRecursive(txGrandChild[0]);
  84     BOOST_CHECK_EQUAL(testPool.size(), poolSize);
  85     poolSize = testPool.size();
  86     testPool.removeRecursive(txChild[0]);
  87     BOOST_CHECK_EQUAL(testPool.size(), poolSize);
  88     // Remove parent, all children/grandchildren should go:
  89     poolSize = testPool.size();
  90     testPool.removeRecursive(txParent);
  91     BOOST_CHECK_EQUAL(testPool.size(), poolSize - 5);
  92     BOOST_CHECK_EQUAL(testPool.size(), 0);
  93
  94     // Add children and grandchildren, but NOT the parent (simulate the parent being in a block)
  95     for (int i = 0; i < 3; i++)
  96     {
  97         testPool.addUnchecked(txChild[i].GetHash(), entry.FromTx(txChild[i]));
  98         testPool.addUnchecked(txGrandChild[i].GetHash(), entry.FromTx(txGrandChild[i]));
  99     }
 100     // Now remove the parent, as might happen if a block-re-org occurs but the parent cannot be
 101     // put into the mempool (maybe because it is non-standard):
 102     poolSize = testPool.size();
 103     testPool.removeRecursive(txParent);
 104     BOOST_CHECK_EQUAL(testPool.size(), poolSize - 6);
 105     BOOST_CHECK_EQUAL(testPool.size(), 0);
 106 }
 107
 108 template<typename name>
 109 void CheckSort(CTxMemPool &pool, std::vector<std::string> &sortedOrder)
 110 {
 111     BOOST_CHECK_EQUAL(pool.size(), sortedOrder.size());
 112     typename CTxMemPool::indexed_transaction_set::index<name>::type::iterator it = pool.mapTx.get<name>().begin();
 113     int count=0;
 114     for (; it != pool.mapTx.get<name>().end(); ++it, ++count) {
 115         BOOST_CHECK_EQUAL(it->GetTx().GetHash().ToString(), sortedOrder[count]);
 116     }
 117 }
 118
 119 BOOST_AUTO_TEST_CASE(MempoolIndexingTest)
 120 {
 121     CTxMemPool pool;
 122     TestMemPoolEntryHelper entry;
 123
 124     /* 3rd highest fee */
 125     CMutableTransaction tx1 = CMutableTransaction();
 126     tx1.vout.resize(1);
 127     tx1.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
 128     tx1.vout[0].nValue = 10 * COIN;
 129     pool.addUnchecked(tx1.GetHash(), entry.Fee(10000LL).FromTx(tx1));
 130
 131     /* highest fee */
 132     CMutableTransaction tx2 = CMutableTransaction();
 133     tx2.vout.resize(1);
 134     tx2.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
 135     tx2.vout[0].nValue = 2 * COIN;
 136     pool.addUnchecked(tx2.GetHash(), entry.Fee(20000LL).FromTx(tx2));
 137
 138     /* lowest fee */
 139     CMutableTransaction tx3 = CMutableTransaction();
 140     tx3.vout.resize(1);
 141     tx3.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
 142     tx3.vout[0].nValue = 5 * COIN;
 143     pool.addUnchecked(tx3.GetHash(), entry.Fee(0LL).FromTx(tx3));
 144
 145     /* 2nd highest fee */
 146     CMutableTransaction tx4 = CMutableTransaction();
 147     tx4.vout.resize(1);
 148     tx4.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
 149     tx4.vout[0].nValue = 6 * COIN;
 150     pool.addUnchecked(tx4.GetHash(), entry.Fee(15000LL).FromTx(tx4));
 151
 152     /* equal fee rate to tx1, but newer */
 153     CMutableTransaction tx5 = CMutableTransaction();
 154     tx5.vout.resize(1);
 155     tx5.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
 156     tx5.vout[0].nValue = 11 * COIN;
 157     entry.nTime = 1;
 158     pool.addUnchecked(tx5.GetHash(), entry.Fee(10000LL).FromTx(tx5));
 159     BOOST_CHECK_EQUAL(pool.size(), 5);
 160
 161     std::vector<std::string> sortedOrder;
 162     sortedOrder.resize(5);
 163     sortedOrder[0] = tx3.GetHash().ToString(); // 0
 164     sortedOrder[1] = tx5.GetHash().ToString(); // 10000
 165     sortedOrder[2] = tx1.GetHash().ToString(); // 10000
 166     sortedOrder[3] = tx4.GetHash().ToString(); // 15000
 167     sortedOrder[4] = tx2.GetHash().ToString(); // 20000
 168     LOCK(pool.cs);
 169     CheckSort<descendant_score>(pool, sortedOrder);
 170
 171     /* low fee but with high fee child */
 172     /* tx6 -> tx7 -> tx8, tx9 -> tx10 */
 173     CMutableTransaction tx6 = CMutableTransaction();
 174     tx6.vout.resize(1);
 175     tx6.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
 176     tx6.vout[0].nValue = 20 * COIN;
 177     pool.addUnchecked(tx6.GetHash(), entry.Fee(0LL).FromTx(tx6));
 178     BOOST_CHECK_EQUAL(pool.size(), 6);
 179     // Check that at this point, tx6 is sorted low
 180     sortedOrder.insert(sortedOrder.begin(), tx6.GetHash().ToString());
 181     CheckSort<descendant_score>(pool, sortedOrder);
 182
 183     CTxMemPool::setEntries setAncestors;
 184     setAncestors.insert(pool.mapTx.find(tx6.GetHash()));
 185     CMutableTransaction tx7 = CMutableTransaction();
 186     tx7.vin.resize(1);
 187     tx7.vin[0].prevout = COutPoint(tx6.GetHash(), 0);
 188     tx7.vin[0].scriptSig = CScript() << OP_11;
 189     tx7.vout.resize(2);
 190     tx7.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
 191     tx7.vout[0].nValue = 10 * COIN;
 192     tx7.vout[1].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
 193     tx7.vout[1].nValue = 1 * COIN;
 194
 195     CTxMemPool::setEntries setAncestorsCalculated;
 196     std::string dummy;
 197     BOOST_CHECK_EQUAL(pool.CalculateMemPoolAncestors(entry.Fee(2000000LL).FromTx(tx7), setAncestorsCalculated, 100, 1000000, 1000, 1000000, dummy), true);
 198     BOOST_CHECK(setAncestorsCalculated == setAncestors);
 199
 200     pool.addUnchecked(tx7.GetHash(), entry.FromTx(tx7), setAncestors);
 201     BOOST_CHECK_EQUAL(pool.size(), 7);
 202
 203     // Now tx6 should be sorted higher (high fee child): tx7, tx6, tx2, ...
 204     sortedOrder.erase(sortedOrder.begin());
 205     sortedOrder.push_back(tx6.GetHash().ToString());
 206     sortedOrder.push_back(tx7.GetHash().ToString());
 207     CheckSort<descendant_score>(pool, sortedOrder);
 208
 209     /* low fee child of tx7 */
 210     CMutableTransaction tx8 = CMutableTransaction();
 211     tx8.vin.resize(1);
 212     tx8.vin[0].prevout = COutPoint(tx7.GetHash(), 0);
 213     tx8.vin[0].scriptSig = CScript() << OP_11;
 214     tx8.vout.resize(1);
 215     tx8.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
 216     tx8.vout[0].nValue = 10 * COIN;
 217     setAncestors.insert(pool.mapTx.find(tx7.GetHash()));
 218     pool.addUnchecked(tx8.GetHash(), entry.Fee(0LL).Time(2).FromTx(tx8), setAncestors);
 219
 220     // Now tx8 should be sorted low, but tx6/tx both high
 221     sortedOrder.insert(sortedOrder.begin(), tx8.GetHash().ToString());
 222     CheckSort<descendant_score>(pool, sortedOrder);
 223
 224     /* low fee child of tx7 */
 225     CMutableTransaction tx9 = CMutableTransaction();
 226     tx9.vin.resize(1);
 227     tx9.vin[0].prevout = COutPoint(tx7.GetHash(), 1);
 228     tx9.vin[0].scriptSig = CScript() << OP_11;
 229     tx9.vout.resize(1);
 230     tx9.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
 231     tx9.vout[0].nValue = 1 * COIN;
 232     pool.addUnchecked(tx9.GetHash(), entry.Fee(0LL).Time(3).FromTx(tx9), setAncestors);
 233
 234     // tx9 should be sorted low
 235     BOOST_CHECK_EQUAL(pool.size(), 9);
 236     sortedOrder.insert(sortedOrder.begin(), tx9.GetHash().ToString());
 237     CheckSort<descendant_score>(pool, sortedOrder);
 238
 239     std::vector<std::string> snapshotOrder = sortedOrder;
 240
 241     setAncestors.insert(pool.mapTx.find(tx8.GetHash()));
 242     setAncestors.insert(pool.mapTx.find(tx9.GetHash()));
 243     /* tx10 depends on tx8 and tx9 and has a high fee*/
 244     CMutableTransaction tx10 = CMutableTransaction();
 245     tx10.vin.resize(2);
 246     tx10.vin[0].prevout = COutPoint(tx8.GetHash(), 0);
 247     tx10.vin[0].scriptSig = CScript() << OP_11;
 248     tx10.vin[1].prevout = COutPoint(tx9.GetHash(), 0);
 249     tx10.vin[1].scriptSig = CScript() << OP_11;
 250     tx10.vout.resize(1);
 251     tx10.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
 252     tx10.vout[0].nValue = 10 * COIN;
 253
 254     setAncestorsCalculated.clear();
 255     BOOST_CHECK_EQUAL(pool.CalculateMemPoolAncestors(entry.Fee(200000LL).Time(4).FromTx(tx10), setAncestorsCalculated, 100, 1000000, 1000, 1000000, dummy), true);
 256     BOOST_CHECK(setAncestorsCalculated == setAncestors);
 257
 258     pool.addUnchecked(tx10.GetHash(), entry.FromTx(tx10), setAncestors);
 259
 260     /**
 261      *  tx8 and tx9 should both now be sorted higher
 262      *  Final order after tx10 is added:
 263      *
 264      *  tx3 = 0 (1)
 265      *  tx5 = 10000 (1)
 266      *  tx1 = 10000 (1)
 267      *  tx4 = 15000 (1)
 268      *  tx2 = 20000 (1)
 269      *  tx9 = 200k (2 txs)
 270      *  tx8 = 200k (2 txs)
 271      *  tx10 = 200k (1 tx)
 272      *  tx6 = 2.2M (5 txs)
 273      *  tx7 = 2.2M (4 txs)
 274      */
 275     sortedOrder.erase(sortedOrder.begin(), sortedOrder.begin()+2); // take out tx9, tx8 from the beginning
 276     sortedOrder.insert(sortedOrder.begin()+5, tx9.GetHash().ToString());
 277     sortedOrder.insert(sortedOrder.begin()+6, tx8.GetHash().ToString());
 278     sortedOrder.insert(sortedOrder.begin()+7, tx10.GetHash().ToString()); // tx10 is just before tx6
 279     CheckSort<descendant_score>(pool, sortedOrder);
 280
 281     // there should be 10 transactions in the mempool
 282     BOOST_CHECK_EQUAL(pool.size(), 10);
 283
 284     // Now try removing tx10 and verify the sort order returns to normal
 285     pool.removeRecursive(pool.mapTx.find(tx10.GetHash())->GetTx());
 286     CheckSort<descendant_score>(pool, snapshotOrder);
 287
 288     pool.removeRecursive(pool.mapTx.find(tx9.GetHash())->GetTx());
 289     pool.removeRecursive(pool.mapTx.find(tx8.GetHash())->GetTx());
 290     /* Now check the sort on the mining score index.
 291      * Final order should be:
 292      *
 293      * tx7 (2M)
 294      * tx2 (20k)
 295      * tx4 (15000)
 296      * tx1/tx5 (10000)
 297      * tx3/6 (0)
 298      * (Ties resolved by hash)
 299      */
 300     sortedOrder.clear();
 301     sortedOrder.push_back(tx7.GetHash().ToString());
 302     sortedOrder.push_back(tx2.GetHash().ToString());
 303     sortedOrder.push_back(tx4.GetHash().ToString());
 304     if (tx1.GetHash() < tx5.GetHash()) {
 305         sortedOrder.push_back(tx5.GetHash().ToString());
 306         sortedOrder.push_back(tx1.GetHash().ToString());
 307     } else {
 308         sortedOrder.push_back(tx1.GetHash().ToString());
 309         sortedOrder.push_back(tx5.GetHash().ToString());
 310     }
 311     if (tx3.GetHash() < tx6.GetHash()) {
 312         sortedOrder.push_back(tx6.GetHash().ToString());
 313         sortedOrder.push_back(tx3.GetHash().ToString());
 314     } else {
 315         sortedOrder.push_back(tx3.GetHash().ToString());
 316         sortedOrder.push_back(tx6.GetHash().ToString());
 317     }
 318     CheckSort<mining_score>(pool, sortedOrder);
 319 }
 320
 321 BOOST_AUTO_TEST_CASE(MempoolAncestorIndexingTest)
 322 {
 323     CTxMemPool pool;
 324     TestMemPoolEntryHelper entry;
 325
 326     /* 3rd highest fee */
 327     CMutableTransaction tx1 = CMutableTransaction();
 328     tx1.vout.resize(1);
 329     tx1.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
 330     tx1.vout[0].nValue = 10 * COIN;
 331     pool.addUnchecked(tx1.GetHash(), entry.Fee(10000LL).FromTx(tx1));
 332
 333     /* highest fee */
 334     CMutableTransaction tx2 = CMutableTransaction();
 335     tx2.vout.resize(1);
 336     tx2.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
 337     tx2.vout[0].nValue = 2 * COIN;
 338     pool.addUnchecked(tx2.GetHash(), entry.Fee(20000LL).FromTx(tx2));
 339     uint64_t tx2Size = GetVirtualTransactionSize(tx2);
 340
 341     /* lowest fee */
 342     CMutableTransaction tx3 = CMutableTransaction();
 343     tx3.vout.resize(1);
 344     tx3.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
 345     tx3.vout[0].nValue = 5 * COIN;
 346     pool.addUnchecked(tx3.GetHash(), entry.Fee(0LL).FromTx(tx3));
 347
 348     /* 2nd highest fee */
 349     CMutableTransaction tx4 = CMutableTransaction();
 350     tx4.vout.resize(1);
 351     tx4.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
 352     tx4.vout[0].nValue = 6 * COIN;
 353     pool.addUnchecked(tx4.GetHash(), entry.Fee(15000LL).FromTx(tx4));
 354
 355     /* equal fee rate to tx1, but newer */
 356     CMutableTransaction tx5 = CMutableTransaction();
 357     tx5.vout.resize(1);
 358     tx5.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
 359     tx5.vout[0].nValue = 11 * COIN;
 360     pool.addUnchecked(tx5.GetHash(), entry.Fee(10000LL).FromTx(tx5));
 361     BOOST_CHECK_EQUAL(pool.size(), 5);
 362
 363     std::vector<std::string> sortedOrder;
 364     sortedOrder.resize(5);
 365     sortedOrder[0] = tx2.GetHash().ToString(); // 20000
 366     sortedOrder[1] = tx4.GetHash().ToString(); // 15000
 367     // tx1 and tx5 are both 10000
 368     // Ties are broken by hash, not timestamp, so determine which
 369     // hash comes first.
 370     if (tx1.GetHash() < tx5.GetHash()) {
 371         sortedOrder[2] = tx1.GetHash().ToString();
 372         sortedOrder[3] = tx5.GetHash().ToString();
 373     } else {
 374         sortedOrder[2] = tx5.GetHash().ToString();
 375         sortedOrder[3] = tx1.GetHash().ToString();
 376     }
 377     sortedOrder[4] = tx3.GetHash().ToString(); // 0
 378
 379     LOCK(pool.cs);
 380     CheckSort<ancestor_score>(pool, sortedOrder);
 381
 382     /* low fee parent with high fee child */
 383     /* tx6 (0) -> tx7 (high) */
 384     CMutableTransaction tx6 = CMutableTransaction();
 385     tx6.vout.resize(1);
 386     tx6.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
 387     tx6.vout[0].nValue = 20 * COIN;
 388     uint64_t tx6Size = GetVirtualTransactionSize(tx6);
 389
 390     pool.addUnchecked(tx6.GetHash(), entry.Fee(0LL).FromTx(tx6));
 391     BOOST_CHECK_EQUAL(pool.size(), 6);
 392     // Ties are broken by hash
 393     if (tx3.GetHash() < tx6.GetHash())
 394         sortedOrder.push_back(tx6.GetHash().ToString());
 395     else
 396         sortedOrder.insert(sortedOrder.end()-1,tx6.GetHash().ToString());
 397
 398     CheckSort<ancestor_score>(pool, sortedOrder);
 399
 400     CMutableTransaction tx7 = CMutableTransaction();
 401     tx7.vin.resize(1);
 402     tx7.vin[0].prevout = COutPoint(tx6.GetHash(), 0);
 403     tx7.vin[0].scriptSig = CScript() << OP_11;
 404     tx7.vout.resize(1);
 405     tx7.vout[0].scriptPubKey = CScript() << OP_11 << OP_EQUAL;
 406     tx7.vout[0].nValue = 10 * COIN;
 407     uint64_t tx7Size = GetVirtualTransactionSize(tx7);
 408
 409     /* set the fee to just below tx2's feerate when including ancestor */
 410     CAmount fee = (20000/tx2Size)*(tx7Size + tx6Size) - 1;
 411
 412     pool.addUnchecked(tx7.GetHash(), entry.Fee(fee).FromTx(tx7));
 413     BOOST_CHECK_EQUAL(pool.size(), 7);
 414     sortedOrder.insert(sortedOrder.begin()+1, tx7.GetHash().ToString());
 415     CheckSort<ancestor_score>(pool, sortedOrder);
 416
 417     /* after tx6 is mined, tx7 should move up in the sort */
 418     std::vector<CTransactionRef> vtx;
 419     vtx.push_back(MakeTransactionRef(tx6));
 420     pool.removeForBlock(vtx, 1);
 421
 422     sortedOrder.erase(sortedOrder.begin()+1);
 423     // Ties are broken by hash
 424     if (tx3.GetHash() < tx6.GetHash())
 425         sortedOrder.pop_back();
 426     else
 427         sortedOrder.erase(sortedOrder.end()-2);
 428     sortedOrder.insert(sortedOrder.begin(), tx7.GetHash().ToString());
 429     CheckSort<ancestor_score>(pool, sortedOrder);
 430 }
 431
 432
 433 BOOST_AUTO_TEST_CASE(MempoolSizeLimitTest)
 434 {
 435     CTxMemPool pool;
 436     TestMemPoolEntryHelper entry;
 437
 438     CMutableTransaction tx1 = CMutableTransaction();
 439     tx1.vin.resize(1);
 440     tx1.vin[0].scriptSig = CScript() << OP_1;
 441     tx1.vout.resize(1);
 442     tx1.vout[0].scriptPubKey = CScript() << OP_1 << OP_EQUAL;
 443     tx1.vout[0].nValue = 10 * COIN;
 444     pool.addUnchecked(tx1.GetHash(), entry.Fee(10000LL).FromTx(tx1));
 445
 446     CMutableTransaction tx2 = CMutableTransaction();
 447     tx2.vin.resize(1);
 448     tx2.vin[0].scriptSig = CScript() << OP_2;
 449     tx2.vout.resize(1);
 450     tx2.vout[0].scriptPubKey = CScript() << OP_2 << OP_EQUAL;
 451     tx2.vout[0].nValue = 10 * COIN;
 452     pool.addUnchecked(tx2.GetHash(), entry.Fee(5000LL).FromTx(tx2));
 453
 454     pool.TrimToSize(pool.DynamicMemoryUsage()); // should do nothing
 455     BOOST_CHECK(pool.exists(tx1.GetHash()));
 456     BOOST_CHECK(pool.exists(tx2.GetHash()));
 457
 458     pool.TrimToSize(pool.DynamicMemoryUsage() * 3 / 4); // should remove the lower-feerate transaction
 459     BOOST_CHECK(pool.exists(tx1.GetHash()));
 460     BOOST_CHECK(!pool.exists(tx2.GetHash()));
 461
 462     pool.addUnchecked(tx2.GetHash(), entry.FromTx(tx2));
 463     CMutableTransaction tx3 = CMutableTransaction();
 464     tx3.vin.resize(1);
 465     tx3.vin[0].prevout = COutPoint(tx2.GetHash(), 0);
 466     tx3.vin[0].scriptSig = CScript() << OP_2;
 467     tx3.vout.resize(1);
 468     tx3.vout[0].scriptPubKey = CScript() << OP_3 << OP_EQUAL;
 469     tx3.vout[0].nValue = 10 * COIN;
 470     pool.addUnchecked(tx3.GetHash(), entry.Fee(20000LL).FromTx(tx3));
 471
 472     pool.TrimToSize(pool.DynamicMemoryUsage() * 3 / 4); // tx3 should pay for tx2 (CPFP)
 473     BOOST_CHECK(!pool.exists(tx1.GetHash()));
 474     BOOST_CHECK(pool.exists(tx2.GetHash()));
 475     BOOST_CHECK(pool.exists(tx3.GetHash()));
 476
 477     pool.TrimToSize(GetVirtualTransactionSize(tx1)); // mempool is limited to tx1's size in memory usage, so nothing fits
 478     BOOST_CHECK(!pool.exists(tx1.GetHash()));
 479     BOOST_CHECK(!pool.exists(tx2.GetHash()));
 480     BOOST_CHECK(!pool.exists(tx3.GetHash()));
 481
 482     CFeeRate maxFeeRateRemoved(25000, GetVirtualTransactionSize(tx3) + GetVirtualTransactionSize(tx2));
 483     BOOST_CHECK_EQUAL(pool.GetMinFee(1).GetFeePerK(), maxFeeRateRemoved.GetFeePerK() + 1000);
 484
 485     CMutableTransaction tx4 = CMutableTransaction();
 486     tx4.vin.resize(2);
 487     tx4.vin[0].prevout.SetNull();
 488     tx4.vin[0].scriptSig = CScript() << OP_4;
 489     tx4.vin[1].prevout.SetNull();
 490     tx4.vin[1].scriptSig = CScript() << OP_4;
 491     tx4.vout.resize(2);
 492     tx4.vout[0].scriptPubKey = CScript() << OP_4 << OP_EQUAL;
 493     tx4.vout[0].nValue = 10 * COIN;
 494     tx4.vout[1].scriptPubKey = CScript() << OP_4 << OP_EQUAL;
 495     tx4.vout[1].nValue = 10 * COIN;
 496
 497     CMutableTransaction tx5 = CMutableTransaction();
 498     tx5.vin.resize(2);
 499     tx5.vin[0].prevout = COutPoint(tx4.GetHash(), 0);
 500     tx5.vin[0].scriptSig = CScript() << OP_4;
 501     tx5.vin[1].prevout.SetNull();
 502     tx5.vin[1].scriptSig = CScript() << OP_5;
 503     tx5.vout.resize(2);
 504     tx5.vout[0].scriptPubKey = CScript() << OP_5 << OP_EQUAL;
 505     tx5.vout[0].nValue = 10 * COIN;
 506     tx5.vout[1].scriptPubKey = CScript() << OP_5 << OP_EQUAL;
 507     tx5.vout[1].nValue = 10 * COIN;
 508
 509     CMutableTransaction tx6 = CMutableTransaction();
 510     tx6.vin.resize(2);
 511     tx6.vin[0].prevout = COutPoint(tx4.GetHash(), 1);
 512     tx6.vin[0].scriptSig = CScript() << OP_4;
 513     tx6.vin[1].prevout.SetNull();
 514     tx6.vin[1].scriptSig = CScript() << OP_6;
 515     tx6.vout.resize(2);
 516     tx6.vout[0].scriptPubKey = CScript() << OP_6 << OP_EQUAL;
 517     tx6.vout[0].nValue = 10 * COIN;
 518     tx6.vout[1].scriptPubKey = CScript() << OP_6 << OP_EQUAL;
 519     tx6.vout[1].nValue = 10 * COIN;
 520
 521     CMutableTransaction tx7 = CMutableTransaction();
 522     tx7.vin.resize(2);
 523     tx7.vin[0].prevout = COutPoint(tx5.GetHash(), 0);
 524     tx7.vin[0].scriptSig = CScript() << OP_5;
 525     tx7.vin[1].prevout = COutPoint(tx6.GetHash(), 0);
 526     tx7.vin[1].scriptSig = CScript() << OP_6;
 527     tx7.vout.resize(2);
 528     tx7.vout[0].scriptPubKey = CScript() << OP_7 << OP_EQUAL;
 529     tx7.vout[0].nValue = 10 * COIN;
 530     tx7.vout[1].scriptPubKey = CScript() << OP_7 << OP_EQUAL;
 531     tx7.vout[1].nValue = 10 * COIN;
 532
 533     pool.addUnchecked(tx4.GetHash(), entry.Fee(7000LL).FromTx(tx4));
 534     pool.addUnchecked(tx5.GetHash(), entry.Fee(1000LL).FromTx(tx5));
 535     pool.addUnchecked(tx6.GetHash(), entry.Fee(1100LL).FromTx(tx6));
 536     pool.addUnchecked(tx7.GetHash(), entry.Fee(9000LL).FromTx(tx7));
 537
 538     // we only require this remove, at max, 2 txn, because its not clear what we're really optimizing for aside from that
 539     pool.TrimToSize(pool.DynamicMemoryUsage() - 1);
 540     BOOST_CHECK(pool.exists(tx4.GetHash()));
 541     BOOST_CHECK(pool.exists(tx6.GetHash()));
 542     BOOST_CHECK(!pool.exists(tx7.GetHash()));
 543
 544     if (!pool.exists(tx5.GetHash()))
 545         pool.addUnchecked(tx5.GetHash(), entry.Fee(1000LL).FromTx(tx5));
 546     pool.addUnchecked(tx7.GetHash(), entry.Fee(9000LL).FromTx(tx7));
 547
 548     pool.TrimToSize(pool.DynamicMemoryUsage() / 2); // should maximize mempool size by only removing 5/7
 549     BOOST_CHECK(pool.exists(tx4.GetHash()));
 550     BOOST_CHECK(!pool.exists(tx5.GetHash()));
 551     BOOST_CHECK(pool.exists(tx6.GetHash()));
 552     BOOST_CHECK(!pool.exists(tx7.GetHash()));
 553
 554     pool.addUnchecked(tx5.GetHash(), entry.Fee(1000LL).FromTx(tx5));
 555     pool.addUnchecked(tx7.GetHash(), entry.Fee(9000LL).FromTx(tx7));
 556
 557     std::vector<CTransactionRef> vtx;
 558     SetMockTime(42);
 559     SetMockTime(42 + CTxMemPool::ROLLING_FEE_HALFLIFE);
 560     BOOST_CHECK_EQUAL(pool.GetMinFee(1).GetFeePerK(), maxFeeRateRemoved.GetFeePerK() + 1000);
 561     // ... we should keep the same min fee until we get a block
 562     pool.removeForBlock(vtx, 1);
 563     SetMockTime(42 + 2*CTxMemPool::ROLLING_FEE_HALFLIFE);
 564     BOOST_CHECK_EQUAL(pool.GetMinFee(1).GetFeePerK(), llround((maxFeeRateRemoved.GetFeePerK() + 1000)/2.0));
 565     // ... then feerate should drop 1/2 each halflife
 566
 567     SetMockTime(42 + 2*CTxMemPool::ROLLING_FEE_HALFLIFE + CTxMemPool::ROLLING_FEE_HALFLIFE/2);
 568     BOOST_CHECK_EQUAL(pool.GetMinFee(pool.DynamicMemoryUsage() * 5 / 2).GetFeePerK(), llround((maxFeeRateRemoved.GetFeePerK() + 1000)/4.0));
 569     // ... with a 1/2 halflife when mempool is < 1/2 its target size
 570
 571     SetMockTime(42 + 2*CTxMemPool::ROLLING_FEE_HALFLIFE + CTxMemPool::ROLLING_FEE_HALFLIFE/2 + CTxMemPool::ROLLING_FEE_HALFLIFE/4);
 572     BOOST_CHECK_EQUAL(pool.GetMinFee(pool.DynamicMemoryUsage() * 9 / 2).GetFeePerK(), llround((maxFeeRateRemoved.GetFeePerK() + 1000)/8.0));
 573     // ... with a 1/4 halflife when mempool is < 1/4 its target size
 574
 575     SetMockTime(42 + 7*CTxMemPool::ROLLING_FEE_HALFLIFE + CTxMemPool::ROLLING_FEE_HALFLIFE/2 + CTxMemPool::ROLLING_FEE_HALFLIFE/4);
 576     BOOST_CHECK_EQUAL(pool.GetMinFee(1).GetFeePerK(), 1000);
 577     // ... but feerate should never drop below 1000
 578
 579     SetMockTime(42 + 8*CTxMemPool::ROLLING_FEE_HALFLIFE + CTxMemPool::ROLLING_FEE_HALFLIFE/2 + CTxMemPool::ROLLING_FEE_HALFLIFE/4);
 580     BOOST_CHECK_EQUAL(pool.GetMinFee(1).GetFeePerK(), 0);
 581     // ... unless it has gone all the way to 0 (after getting past 1000/2)
 582
 583     SetMockTime(0);
 584 }
 585
 586 BOOST_AUTO_TEST_SUITE_END()