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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server440 file guides

Release published 2026-10-28 · Snapshot fetched 2026-11-01. Latest stable release at fetch time; development branches and Git history are excluded. Only the selected code window and visible folders load here.

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1// Copyright (c) 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 <kernel/mempool_entry.h>
6#include <policy/fees/estimator_args.h>
7#include <policy/fees/mempool_estimator.h>
8#include <policy/policy.h>
9#include <primitives/block.h>
10#include <random.h>
11#include <test/util/setup_common.h>
12#include <test/util/txmempool.h>
13#include <txmempool.h>
14#include <uint256.h>
15#include <util/feefrac.h>
16#include <util/fees.h>
17#include <util/time.h>
18#include <validation.h>
19
20#include <boost/test/unit_test.hpp>
21
22#include <string>
23
24BOOST_FIXTURE_TEST_SUITE(mempool_fee_estimator_tests, TestingSetup)
25
26static inline CTransactionRef MakeRandomTx()
27{
28    auto rng = FastRandomContext();
29    auto tx = CMutableTransaction();
30    tx.vin.resize(1);
31    tx.vout.resize(1);
32    tx.vin[0].prevout.hash = Txid::FromUint256(rng.rand256());
33    tx.vin[0].prevout.n = 0;
34    tx.vin[0].scriptSig << OP_TRUE;
35    tx.vout[0].scriptPubKey = CScript() << OP_TRUE;
36    tx.vout[0].nValue = COIN;
37    return MakeTransactionRef(tx);
38}
39
40void AddRemovedBlock(MemPoolFeeRateEstimator& fee_est,
41                     int32_t removed_txs_weight,
42                     int32_t block_txs_weight,
43                     unsigned int& height)
44{
45    auto block = std::make_shared<CBlock>();
46    std::vector<RemovedMempoolTransactionInfo> removed_txs;
47    TestMemPoolEntryHelper entry;
48    Assert(block_txs_weight >= removed_txs_weight);
49    block->vtx.emplace_back(MakeRandomTx()); // Add a coinbase tx
50    while (block_txs_weight > 0) {
51        auto tx = MakeRandomTx();
52        auto tx_weight = GetTransactionWeight(*tx);
53        if (block_txs_weight - tx_weight < 0) break;
54        block->vtx.emplace_back(tx);
55        block_txs_weight -= tx_weight;
56        if (removed_txs_weight - tx_weight >= 0) {
57            removed_txs.emplace_back(entry.FromTx(tx));
58            removed_txs_weight -= tx_weight;
59        }
60    }
61    fee_est.MempoolTxsRemovedForBlock(block, removed_txs, height);
62    height += 1;
63}
64
65BOOST_AUTO_TEST_CASE(calculate_max_weight_percentiles)
66{
67    // With no chunks neither percentile can be populated.
68    const auto empty = MemPoolFeeRateEstimator::CalculateMaxWeightPercentiles({});
69    BOOST_CHECK(empty.p50.IsEmpty());
70    BOOST_CHECK(empty.p75.IsEmpty());
71    const int32_t chunk_size{10};
72    const int32_t individual_tx_vsize = static_cast<int32_t>(DEFAULT_BLOCK_MAX_WEIGHT / WITNESS_SCALE_FACTOR) / chunk_size;
73    const FeePerVSize super_high_fee_rate{500 * individual_tx_vsize, individual_tx_vsize};
74    const FeePerVSize high_fee_rate{100 * individual_tx_vsize, individual_tx_vsize};
75    const FeePerVSize medium_fee_rate{50 * individual_tx_vsize, individual_tx_vsize};
76    const FeePerVSize low_fee_rate{10 * individual_tx_vsize, individual_tx_vsize};
77    std::vector<FeePerVSize> chunk_feerates;
78    chunk_feerates.reserve(chunk_size);
79    for (int i = 0; i < chunk_size; ++i) {
80        if (i < 3) {
81            chunk_feerates.emplace_back(super_high_fee_rate);
82        } else if (i < 5) {
83            chunk_feerates.emplace_back(high_fee_rate);
84        } else if (i < 8) {
85            chunk_feerates.emplace_back(medium_fee_rate);
86            // Once 50% coverage is reached but 75% is not, only the p50 (conservative)
87            // percentile is populated; p75 (economical) is left empty for the caller to floor.
88            if (i < 7) {
89                const auto partial = MemPoolFeeRateEstimator::CalculateMaxWeightPercentiles(chunk_feerates);
90                BOOST_CHECK_EQUAL(partial.p50.fee, high_fee_rate.fee);
91                BOOST_CHECK_EQUAL(partial.p50.size, high_fee_rate.size);
92                BOOST_CHECK(partial.p75.IsEmpty());
93            }
94        } else {
95            chunk_feerates.emplace_back(low_fee_rate);
96        }
97    }
98    const auto percentiles = MemPoolFeeRateEstimator::CalculateMaxWeightPercentiles(chunk_feerates);
99    BOOST_CHECK_EQUAL(percentiles.p50.fee, high_fee_rate.fee);
100    BOOST_CHECK_EQUAL(percentiles.p50.size, high_fee_rate.size);
101    BOOST_CHECK_EQUAL(percentiles.p75.fee, medium_fee_rate.fee);
102    BOOST_CHECK_EQUAL(percentiles.p75.size, medium_fee_rate.size);
103    BOOST_CHECK(ByRatio{percentiles.p50} > ByRatio{percentiles.p75});
104}
105
106BOOST_AUTO_TEST_CASE(mempool_fee_rate_estimator_cache)
107{
108    FakeNodeClock clock{};
109    MemPoolFeeRateEstimatorCache cache;
110    const uint256 tip_hash{uint256::ONE};
111    const uint256 next_tip_hash{uint256{2}};
112    const FeePerVSize conservative{2, 1};
113    const FeePerVSize economical{1, 1};
114
115    BOOST_CHECK(cache.IsStale());
116    BOOST_CHECK(!cache.GetCachedEstimate(tip_hash));
117
118    cache.Update(conservative, economical, tip_hash);
119    BOOST_CHECK(!cache.IsStale());
120    const auto cached{cache.GetCachedEstimate(tip_hash)};
121    BOOST_REQUIRE(cached);
122    BOOST_CHECK(cached->m_conservative == conservative);
123    BOOST_CHECK(cached->m_economical == economical);
124    BOOST_CHECK(!cache.GetCachedEstimate(next_tip_hash));
125
126    clock += CACHE_LIFE + std::chrono::seconds{1};
127    BOOST_CHECK(cache.IsStale());
128    BOOST_CHECK(!cache.GetCachedEstimate(tip_hash));
129}
130
131BOOST_AUTO_TEST_CASE(MempoolFeeRateEstimator)
132{
133    auto mempool_estimator = MemPoolFeeRateEstimator(MempoolPolicyEstimatorPath(*m_node.args), *m_node.mempool, *m_node.chainman);
134    BOOST_CHECK_EQUAL(mempool_estimator.MaximumTarget(), MEMPOOL_FEE_ESTIMATOR_MAX_TARGET);
135    // Before the mempool has finished loading, no estimate is available.
136    {
137        const std::string unloaded_err = strprintf("%s: Mempool not loaded yet, no fee rate estimate available",
138                                                   FeeRateEstimatorTypeToString(FeeRateEstimatorType::MEMPOOL_POLICY));
139        const auto result = mempool_estimator.EstimateFeeRate(/*conservative=*/true);
140        BOOST_CHECK(!result);
141        BOOST_CHECK_EQUAL(result.error().reason, unloaded_err);
142    }
143    m_node.mempool->SetLoadTried(true);
144
145    BOOST_CHECK(!mempool_estimator.IsMempoolHealthy());
146    BOOST_CHECK(mempool_estimator.GetMempoolHealth() == MemPoolFeeRateEstimator::MempoolHealth::INSUFFICIENT_DATA);
147    {
148        const auto result = mempool_estimator.EstimateFeeRate(/*conservative=*/true);
149        const std::string insufficient_err{strprintf("%s: Not enough recent block data for fee rate estimation",
150                                                     FeeRateEstimatorTypeToString(FeeRateEstimatorType::MEMPOOL_POLICY))};
151        BOOST_CHECK(!result);
152        BOOST_CHECK_EQUAL(result.error().reason, insufficient_err);
153    }
154    {
155        MemPoolFeeRateEstimator custom_mempool_estimator{
156            MempoolPolicyEstimatorPath(*m_node.args), *m_node.mempool, *m_node.chainman};
157        unsigned int custom_height{100};
158        for (size_t block_count{1}; block_count < MEMPOOL_HEALTH_WINDOW_BLOCKS; ++block_count) {
159            AddRemovedBlock(custom_mempool_estimator,
160                            /*removed_txs_weight=*/0,
161                            /*block_txs_weight=*/0,
162                            custom_height);
163            BOOST_CHECK(!custom_mempool_estimator.IsMempoolHealthy());
164        }
165        {
166            const int64_t low_activity_weight{1000};
167            AddRemovedBlock(custom_mempool_estimator, low_activity_weight / 2, low_activity_weight, custom_height);
168        }
169        // Below one block worth of total activity across the full window, even
170        // poor coverage in the only non-empty block is too noisy to reject the
171        // mempool as unhealthy.
172        BOOST_CHECK(custom_mempool_estimator.IsMempoolHealthy());
173    }
174    size_t block_count = 1;
175    const int64_t weight{DEFAULT_BLOCK_MAX_WEIGHT / 2};
176    unsigned int height = 100;
177    // Equal weight
178    while (block_count <= MEMPOOL_HEALTH_WINDOW_BLOCKS) {
179        AddRemovedBlock(mempool_estimator, weight, weight, height);
180        if (block_count < MEMPOOL_HEALTH_WINDOW_BLOCKS) {
181            BOOST_CHECK(!mempool_estimator.IsMempoolHealthy());
182        }
183        block_count += 1;
184    }
185    // Total txs weight ~11999k WU (~3.0 blocks), removed txs ~11999k WU (~3.0 blocks); coverage = 100%.
186    BOOST_CHECK(mempool_estimator.IsMempoolHealthy());
187    // Adding a single underrepresented block will not make the mempool unhealthy
188    // while the window coverage remains above the threshold.
189    AddRemovedBlock(mempool_estimator, weight / 2, weight, height);
190    // Total txs weight ~11999k WU (~3.0 blocks), removed txs ~10999k WU (~2.75 blocks); coverage = ~92%.
191    BOOST_CHECK(mempool_estimator.IsMempoolHealthy());
192    // Empty block
193    // Total txs weight ~9999k WU (~2.5 blocks), removed txs ~8999k WU (~2.25 blocks); coverage = 90%.
194    AddRemovedBlock(mempool_estimator, 0, 0, height);
195    BOOST_CHECK(mempool_estimator.IsMempoolHealthy());
196    // Total txs weight ~9999k WU (~2.5 blocks), removed txs ~7999k WU (~2.0 blocks); coverage = 80%.
197    AddRemovedBlock(mempool_estimator, weight / 2, weight, height);
198    BOOST_CHECK(mempool_estimator.IsMempoolHealthy());
199    // Total txs weight ~9999k WU (~2.5 blocks), removed txs ~7000k WU (~1.75 blocks); coverage = 70%.
200    AddRemovedBlock(mempool_estimator, weight / 2, weight, height);
201    BOOST_CHECK(!mempool_estimator.IsMempoolHealthy());
202    block_count = 1;
203    while (block_count <= 3) {
204        AddRemovedBlock(mempool_estimator, weight, weight, height);
205        if (block_count < 3) {
206            BOOST_CHECK(!mempool_estimator.IsMempoolHealthy());
207        }
208        block_count += 1;
209    }
210    // Total txs weight ~9999k WU (~2.5 blocks), removed txs ~7999k WU (~2.0 blocks); coverage = 80%.
211    BOOST_CHECK(mempool_estimator.IsMempoolHealthy());
212
213    // Reorg out and replace the last block. Replacing the tip block should keep a full
214    // healthy window when the replacement block has good mempool representation.
215    height -= 1;
216    AddRemovedBlock(mempool_estimator, weight, weight, height);
217    BOOST_CHECK(mempool_estimator.IsMempoolHealthy());
218
219    // Reorg out the last two blocks. The estimator should discard the stale suffix,
220    // become temporarily unhealthy due to having fewer than MEMPOOL_HEALTH_WINDOW_BLOCKS stats,
221    // then recover after the replacement chain catches up.
222    height -= 2;
223    AddRemovedBlock(mempool_estimator, weight, weight, height);
224    BOOST_CHECK(!mempool_estimator.IsMempoolHealthy());
225    AddRemovedBlock(mempool_estimator, weight, weight, height);
226    BOOST_CHECK(mempool_estimator.IsMempoolHealthy());
227
228    // A forward height gap (e.g. stale persisted stats after an unclean shutdown
229    // while the chain advanced) resets the tracked window entirely; the estimator
230    // stays unhealthy until a full window of contiguous blocks is seen again.
231    height += 3;
232    AddRemovedBlock(mempool_estimator, weight, weight, height);
233    BOOST_CHECK(!mempool_estimator.IsMempoolHealthy());
234    for (size_t i = 1; i < MEMPOOL_HEALTH_WINDOW_BLOCKS; ++i) {
235        AddRemovedBlock(mempool_estimator, weight, weight, height);
236        if (i < MEMPOOL_HEALTH_WINDOW_BLOCKS - 1) {
237            BOOST_CHECK(!mempool_estimator.IsMempoolHealthy());
238        }
239    }
240    BOOST_CHECK(mempool_estimator.IsMempoolHealthy());
241    {
242        LOCK(m_node.mempool->cs);
243        BOOST_CHECK_EQUAL(m_node.mempool->GetTotalTxSize(), 0);
244    }
245    // With an empty mempool there is nothing to build a feerate estimate from, so both
246    // estimates fall back to the floor fee rate: the higher of the minimum relay fee rate
247    // and the current mempool minimum fee rate.
248    const FeePerVSize floor{std::max(m_node.mempool->m_opts.min_relay_feerate, m_node.mempool->GetMinFee()).GetFeePerVSize()};
249    {
250        const auto result = mempool_estimator.EstimateFeeRate(/*conservative=*/true);

src/wallet/receive.cpp

src/wallet/coinselection.cpp

src/consensus/validation.h

src/primitives/transaction.cpp

src/script/descriptor.cpp

src/bitcoin-cli.cpp

src/rpc/blockchain.cpp

src/rpc/rawtransaction.cpp

src/init.cpp

src/crypto/sha256.cpp

src/consensus/merkle.h

src/consensus/tx_check.h

src/consensus/tx_verify.h

src/policy/feerate.h

src/policy/feerate.cpp

src/primitives/transaction_identifier.h

src/chainparamsbase.h

src/chainparamsbase.cpp

src/util/moneystr.cpp

src/crypto/ripemd160.h

src/crypto/sha1.h

src/crypto/sha512.h

src/crypto/hmac_sha256.h

src/crypto/hmac_sha512.h

src/crypto/hmac_sha256.cpp

src/crypto/hmac_sha512.cpp

src/crypto/hkdf_sha256_32.h

src/crypto/hkdf_sha256_32.cpp

src/support/cleanse.h

src/support/cleanse.cpp

src/crypto/siphash.cpp

src/crypto/muhash.h

src/crypto/chacha20.h

src/crypto/poly1305.h

src/crypto/chacha20poly1305.h

src/crypto/chacha20poly1305.cpp

src/util/chaintype.cpp

src/util/obfuscation.h

src/util/byte_units.h

src/util/overflow.h

src/blockencodings.cpp

src/net_permissions.cpp

src/policy/packages.cpp

src/policy/rbf.cpp

src/policy/truc_policy.cpp

src/policy/ephemeral_policy.cpp

src/policy/settings.cpp

src/policy/policy.cpp

src/node/transaction.cpp

src/node/coin.cpp

src/rpc/client.cpp

src/rpc/external_signer.cpp

src/rpc/request.cpp

src/rpc/server_util.cpp

src/rpc/fees.cpp

src/rpc/output_script.cpp

src/rpc/rawtransaction_util.cpp

src/rpc/rawtransaction_util.h

src/rpc/register.h

src/rpc/request.h

src/rpc/server_util.h

src/rpc/protocol.h

src/rpc/server.h

src/rpc/signmessage.cpp

src/rpc/txoutproof.cpp

src/rpc/util.cpp

src/rpc/util.h

src/wallet/rpc/addresses.cpp

src/wallet/rpc/backup.cpp

src/wallet/rpc/coins.cpp

src/wallet/rpc/encrypt.cpp

src/wallet/rpc/signmessage.cpp

src/wallet/rpc/util.cpp

src/wallet/rpc/util.h

src/wallet/coincontrol.cpp

src/wallet/coincontrol.h

src/wallet/context.cpp

src/wallet/context.h

src/wallet/crypter.cpp

src/wallet/crypter.h

src/wallet/db.cpp

src/wallet/export.cpp

src/wallet/external_signer_scriptpubkeyman.cpp

src/wallet/rpc/spend.cpp

src/wallet/rpc/transactions.cpp

src/wallet/rpc/wallet.cpp

src/wallet/feebumper.cpp

src/wallet/feebumper.h

src/index/base.h

src/index/base.cpp

src/index/txindex.h

src/index/txindex.cpp

src/index/txindex_key.h

src/index/txospenderindex.h

src/index/txospenderindex.cpp

src/index/blockfilterindex.h

src/index/blockfilterindex.cpp

src/index/coinstatsindex.h

src/index/coinstatsindex.cpp

src/index/db_key.h

src/index/disktxpos.h

src/kernel/chain.cpp

src/kernel/chain.h

src/kernel/checks.cpp

src/kernel/checks.h

src/kernel/context.cpp

src/kernel/context.h

src/kernel/cs_main.cpp

src/kernel/cs_main.h

src/kernel/disconnected_transactions.cpp

src/kernel/disconnected_transactions.h

src/kernel/mempool_removal_reason.cpp

src/kernel/mempool_removal_reason.h

src/kernel/coinstats.cpp

src/kernel/coinstats.h

src/kernel/chainparams.cpp

src/kernel/chainparams.h

src/wallet/sqlite.cpp

src/wallet/sqlite.h

src/wallet/transaction.cpp

src/wallet/transaction.h

src/wallet/dump.cpp

src/wallet/dump.h

src/wallet/init.cpp

src/wallet/walletutil.cpp

src/wallet/walletutil.h

src/wallet/wallettool.cpp

src/wallet/wallettool.h

src/wallet/export.h

src/wallet/migrate.cpp

src/wallet/migrate.h

src/wallet/db.h

src/wallet/walletdb.cpp

src/wallet/interfaces.cpp

src/wallet/scriptpubkeyman.cpp

src/wallet/scriptpubkeyman.h

src/kernel/bitcoinkernel.cpp

src/kernel/bitcoinkernel.h

src/kernel/bitcoinkernel_wrapper.h

src/node/chainstate.cpp

src/node/chainstate.h

src/node/blockstorage.cpp

src/node/blockstorage.h

src/node/mempool_persist.cpp

src/node/mempool_persist.h

src/node/utxo_snapshot.cpp

src/node/utxo_snapshot.h

src/node/kernel_notifications.cpp

src/node/kernel_notifications.h

src/node/blockmanager_args.cpp

src/kernel/blockmanager_opts.h

src/util/expected.cpp

src/policy/settings.h

src/util/types.h

src/kernel/messagestartchars.h

src/kernel/warning.h

src/util/exception.h

src/common/license_info.h

src/node/coins_view_args.h

src/node/database_args.h

src/util/batchpriority.h

src/util/ui_change_type.h

src/node/coins_view_args.cpp

src/node/peerman_args.h

src/util/serfloat.h

src/node/blockmanager_args.h

src/node/database_args.cpp

src/util/overloaded.h

src/interfaces/types.h

src/node/chainstatemanager_args.h

src/node/minisketchwrapper.h

src/util/macros.h

src/util/syserror.h

src/common/run_command.h

src/util/bytevectorhash.cpp

src/node/mempool_persist_args.cpp

src/util/exec.h

src/util/rbf.h

src/crypto/hex_base.h

src/node/mempool_persist_args.h

src/interfaces/echo.h

src/util/any.h

src/util/batchpriority.cpp

src/util/threadnames.h

src/node/coin.h

src/node/mempool_args.h

src/util/asmap.h

src/util/bytevectorhash.h

src/node/context.cpp

src/util/insert.h

src/util/readwritefile.h

src/node/peerman_args.cpp

src/node/interface_ui.cpp

src/interfaces/handler.h

src/node/mining_args.h

src/util/hasher.cpp

src/common/init.h

src/kernel/mempool_limits.h

src/common/system.h

src/crypto/sha3.h

src/util/threadinterrupt.cpp

src/node/protocol_version.h

src/util/exception.cpp

src/common/messages.h

src/node/connection_types.cpp

src/util/bip32.h

src/common/license_info.cpp

src/util/stdmutex.h

src/common/run_command.cpp

src/util/check.cpp

src/util/golombrice.h

src/node/types.h

src/node/timeoffsets.h

src/util/readwritefile.cpp

src/util/fastrange.h

src/util/signalinterrupt.h

src/util/task_runner.h

src/util/syserror.cpp

src/common/interfaces.cpp

src/common/types.h

src/util/threadinterrupt.h

src/kernel/chainstatemanager_opts.h

src/node/psbt.h

src/policy/ephemeral_policy.h

src/util/trace.h

src/common/url.cpp

src/kernel/mempool_options.h

src/util/serfloat.cpp

src/kernel/notifications_interface.h

src/node/timeoffsets.cpp

src/node/warnings.cpp

src/util/hash_type.h

src/crypto/hex_base.cpp

src/node/eviction.h

src/util/tokenbucket.h

src/crypto/aes.h

src/common/pcp.h

src/util/feefrac.cpp

src/node/transaction.h

src/util/threadnames.cpp

src/common/signmessage.h

src/util/exec.cpp

src/util/signalinterrupt.cpp

src/clientversion.cpp

src/common/signmessage.cpp

src/compat/assumptions.h

src/compat/byteswap.h

src/deploymentinfo.cpp

src/deploymentinfo.h

src/deploymentstatus.cpp

src/deploymentstatus.h

src/dummywallet.cpp

src/external_signer.h

src/init/bitcoin-gui.cpp

src/init/bitcoin-node.cpp

src/init/bitcoin-qt.cpp

src/init/bitcoin-wallet.cpp

src/init/bitcoind.cpp

src/init/common.h

src/interfaces/init.h

src/interfaces/ipc.h

src/key_io.h

src/logging/categories.h

src/logging/timer.h

src/mapport.h

src/musig.h

src/net_permissions.h

src/netgroup.h

src/netmessagemaker.h

src/node/chainstatemanager_args.cpp

src/node/connection_types.h

src/node/context.h

src/node/interface_ui.h

src/node/mempool_args.cpp

src/node/mining_args.cpp

src/node/minisketchwrapper.cpp

src/node/txreconciliation.h

src/policy/fees/estimator_args.cpp

src/policy/fees/estimator_args.h

src/policy/fees/estimator_man.cpp

src/policy/fees/estimator_man.h

src/policy/packages.h

src/policy/rbf.h

src/policy/truc_policy.h

src/pow.h

src/primitives/block.cpp

src/randomenv.h

src/rest.h

src/script/keyorigin.h

src/script/parsing.cpp

src/script/parsing.h

src/script/script_error.h

src/script/sigcache.cpp

src/script/sigcache.h

src/script/solver.h

src/script/verify_flags.h

src/semaphore_grant.h

src/signet.h

src/span.h

src/support/allocators/secure.h

src/support/allocators/zeroafterfree.h

src/util/tokenpipe.cpp

src/util/translation.h

src/util/vector.h

src/versionbits.h

src/versionbits_impl.h

src/wallet/external_signer_scriptpubkeyman.h

src/wallet/fees.h

src/wallet/load.h

src/wallet/receive.h

src/wallet/rpc/wallet.h

src/wallet/types.h

src/walletinitinterface.h

src/zmq/zmqabstractnotifier.cpp

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