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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server340 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.

18,915 bytes · SHA-256 c3de1e7952e7c2d9… · View upstream ↗

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 <policy/fees/mempool_estimator.h>
6
7#include <logging.h>
8#include <node/miner.h>
9#include <policy/feerate.h>
10#include <policy/policy.h>
11#include <primitives/block.h>
12#include <serialize.h>
13#include <streams.h>
14#include <sync.h>
15#include <tinyformat.h>
16#include <txmempool.h>
17#include <util/check.h>
18#include <util/feefrac.h>
19#include <util/fees.h>
20#include <util/fs.h>
21#include <util/overflow.h>
22#include <util/syserror.h>
23#include <validation.h>
24
25#include <algorithm>
26#include <iterator>
27#include <numeric>
28#include <optional>
29#include <string>
30#include <string_view>
31#include <system_error>
32#include <utility>
33
34constexpr int CURRENT_MEMPOOL_ESTIMATOR_VERSION{1};
35
36namespace {
37struct MinedBlockStatsFormatter {
38    template <typename Stream>
39    void Ser(Stream& s, const MinedBlockStats& v)
40    {
41        s << v.m_height << v.m_removed_block_txs_weight << v.m_block_weight;
42    }
43    template <typename Stream>
44    void Unser(Stream& s, MinedBlockStats& v)
45    {
46        s >> v.m_height >> v.m_removed_block_txs_weight >> v.m_block_weight;
47    }
48};
49
50void AddMinedBlockStats(std::vector<MinedBlockStats>& mined_blocks, MinedBlockStats stats)
51{
52    const auto stale_begin{std::find_if(mined_blocks.begin(), mined_blocks.end(), [&](const MinedBlockStats& block) {
53        return block.m_height >= stats.m_height;
54    })};
55    const auto stale_count{std::distance(stale_begin, mined_blocks.end())};
56    if (stale_count > 0) {
57        LogDebug(BCLog::ESTIMATEFEE,
58                 "%s: connected block height=%s discards tracked mined-block stats "
59                 "from height=%s to height=%s; stale_stats=%s",
60                 FeeRateEstimatorTypeToString(FeeRateEstimatorType::MEMPOOL_POLICY),
61                 stats.m_height,
62                 stale_begin->m_height,
63                 mined_blocks.back().m_height,
64                 stale_count);
65    }
66    mined_blocks.erase(stale_begin, mined_blocks.end());
67    if (!mined_blocks.empty() && mined_blocks.back().m_height + 1 != stats.m_height) {
68        LogDebug(BCLog::ESTIMATEFEE,
69                 "%s: clearing mined-block stats after height gap; tracked_stats=%s "
70                 "expected_height=%s received_height=%s",
71                 FeeRateEstimatorTypeToString(FeeRateEstimatorType::MEMPOOL_POLICY),
72                 mined_blocks.size(),
73                 mined_blocks.back().m_height + 1,
74                 stats.m_height);
75        mined_blocks.clear();
76    }
77
78    if (mined_blocks.size() == MEMPOOL_HEALTH_WINDOW_BLOCKS) mined_blocks.erase(mined_blocks.begin());
79    mined_blocks.push_back(stats);
80}
81
82struct ActiveTip {
83    int height;
84    uint256 hash;
85};
86
87std::optional<ActiveTip> GetActiveTip(const ChainstateManager& chainman)
88{
89    LOCK(::cs_main);
90    const CBlockIndex* tip{chainman.ActiveTip()};
91    if (!tip) return std::nullopt;
92    return ActiveTip{tip->nHeight, tip->GetBlockHash()};
93}
94} // namespace
95
96MemPoolFeeRateEstimator::Percentiles MemPoolFeeRateEstimator::CalculateMaxWeightPercentiles(std::span<const FeePerVSize> chunk_feerates)
97{
98    Assume(std::is_sorted(chunk_feerates.begin(), chunk_feerates.end(), [](const auto& a, const auto& b) { return ByRatio{a} > ByRatio{b}; }));
99    constexpr int64_t total_weight{DEFAULT_BLOCK_MAX_WEIGHT};
100    const int64_t p50_weight{total_weight / 2};
101    const int64_t p75_weight{total_weight * 3 / 4};
102    Percentiles percentiles{};
103    int64_t accumulated_weight{0};
104    for (const auto& curr_feerate : chunk_feerates) {
105        accumulated_weight += int64_t{curr_feerate.size} * WITNESS_SCALE_FACTOR;
106        if (accumulated_weight >= p50_weight && percentiles.p50.IsEmpty()) {
107            percentiles.p50 = curr_feerate;
108        }
109        if (accumulated_weight >= p75_weight && percentiles.p75.IsEmpty()) {
110            percentiles.p75 = curr_feerate;
111            break;
112        }
113    }
114    return percentiles;
115}
116
117bool MemPoolFeeRateEstimatorCache::IsStale() const
118{
119    return !m_fee_rate_estimation || (m_last_updated + CACHE_LIFE) < NodeClock::now();
120}
121
122std::optional<MemPoolFeeRateEstimatorCache::FeeRateEstimate>
123MemPoolFeeRateEstimatorCache::GetCachedEstimate(const uint256& tip_hash) const
124{
125    if (IsStale() || tip_hash != m_tip_hash) return std::nullopt;
126    return m_fee_rate_estimation;
127}
128
129void MemPoolFeeRateEstimatorCache::Update(FeePerVSize conservative, FeePerVSize economical, const uint256& tip_hash)
130{
131    m_fee_rate_estimation = {conservative, economical};
132    m_tip_hash = tip_hash;
133    m_last_updated = NodeClock::now();
134}
135
136void MemPoolFeeRateEstimatorCache::Clear()
137{
138    m_fee_rate_estimation.reset();
139    m_tip_hash.SetNull();
140    m_last_updated = {};
141}
142
143//! Build the error result for a failed mempool fee rate estimation.
144static util::Unexpected<FeeRateEstimationError> EstimationError(std::string error)
145{
146    return EstimationError(FeeRateEstimatorType::MEMPOOL_POLICY, MEMPOOL_FEE_ESTIMATOR_MAX_TARGET, std::move(error));
147}
148
149static std::optional<std::string_view> MempoolHealthError(MemPoolFeeRateEstimator::MempoolHealth health)
150{
151    switch (health) {
152    case MemPoolFeeRateEstimator::MempoolHealth::INSUFFICIENT_DATA:
153        return "Not enough recent block data for fee rate estimation";
154    case MemPoolFeeRateEstimator::MempoolHealth::LOW_COVERAGE:
155        return "Mempool is unreliable for fee rate estimation";
156    case MemPoolFeeRateEstimator::MempoolHealth::HEALTHY:
157        return std::nullopt;
158    }
159    Assume(false);
160    return std::nullopt;
161}
162
163MemPoolFeeRateEstimator::MemPoolFeeRateEstimator(fs::path mempool_estimator_file_path,
164                                                 const CTxMemPool& mempool,
165                                                 ChainstateManager& chainman)
166    : m_mempool(mempool),
167      m_chainman(chainman),
168      m_mempool_estimator_file_path(std::move(mempool_estimator_file_path))
169{
170    ReadFromDisk();
171}
172
173void MemPoolFeeRateEstimator::ReadFromDisk()
174{
175    AutoFile file{fsbridge::fopen(m_mempool_estimator_file_path, "rb")};
176    if (file.IsNull()) {
177        LogDebug(BCLog::ESTIMATEFEE, "%s: %s does not exist. Continuing anyway",
178                 FeeRateEstimatorTypeToString(FeeRateEstimatorType::MEMPOOL_POLICY),
179                 fs::PathToString(m_mempool_estimator_file_path));
180        return;
181    }
182    if (Read(file)) {
183        LogDebug(BCLog::ESTIMATEFEE, "%s: mined-block stats successfully read from %s.",
184                 FeeRateEstimatorTypeToString(FeeRateEstimatorType::MEMPOOL_POLICY),
185                 fs::PathToString(m_mempool_estimator_file_path));
186    }
187}
188
189bool MemPoolFeeRateEstimator::Read(AutoFile& file)
190{
191    try {
192        int version_required;
193        file >> version_required;
194        if (version_required != CURRENT_MEMPOOL_ESTIMATOR_VERSION) {
195            LogWarning("%s: file version not supported; continuing anyway",
196                       FeeRateEstimatorTypeToString(FeeRateEstimatorType::MEMPOOL_POLICY));
197            return false;
198        }
199        // Stage into a local buffer and commit to the member only after validation passes.
200        std::vector<MinedBlockStats> blocks;
201        file >> Using<VectorFormatter<MinedBlockStatsFormatter>>(blocks);
202        uint256 tip_hash;
203        file >> tip_hash;
204        if (blocks.size() > MEMPOOL_HEALTH_WINDOW_BLOCKS) {
205            LogWarning("%s: Number of previously mined blocks read exceeds the maximum of %s; ignoring file",
206                       FeeRateEstimatorTypeToString(FeeRateEstimatorType::MEMPOOL_POLICY),
207                       MEMPOOL_HEALTH_WINDOW_BLOCKS);
208            return false;
209        }
210        for (size_t i = 1; i < blocks.size(); ++i) {
211            const uint64_t expected_height{SaturatingAdd(blocks[i - 1].m_height, uint64_t{1})};
212            if (blocks[i].m_height != expected_height) {
213                LogWarning("%s: Non-consecutive block heights read, expected height %s but found %s; ignoring file",
214                           FeeRateEstimatorTypeToString(FeeRateEstimatorType::MEMPOOL_POLICY),
215                           expected_height, blocks[i].m_height);
216                return false;
217            }
218        }
219        if (!blocks.empty()) {
220            const auto& last_block{blocks.back()};
221            const std::optional<ActiveTip> active_tip{GetActiveTip(m_chainman)};
222            if (!active_tip) {
223                LogWarning("%s: Mined-block stats read end at height %s block %s, but there is no active chain tip; ignoring file",
224                           FeeRateEstimatorTypeToString(FeeRateEstimatorType::MEMPOOL_POLICY),
225                           last_block.m_height, tip_hash.ToString());
226                return false;
227            }
228            if (last_block.m_height != static_cast<uint64_t>(active_tip->height) || tip_hash != active_tip->hash) {
229                LogWarning("%s: Mined-block stats read end at height %s block %s, but the active chain tip is height %s block %s; ignoring file",
230                           FeeRateEstimatorTypeToString(FeeRateEstimatorType::MEMPOOL_POLICY),
231                           last_block.m_height, tip_hash.ToString(),
232                           active_tip->height, active_tip->hash.ToString());
233                return false;
234            }
235        }
236        LOCK(cs);
237        m_prev_mined_blocks = std::move(blocks);
238        m_mined_blocks_tip_hash = tip_hash;
239        m_cache.Clear();
240    } catch (const std::exception&) {
241        LogWarning("%s: Unable to read mined-block stats from stream (non-fatal)",
242                   FeeRateEstimatorTypeToString(FeeRateEstimatorType::MEMPOOL_POLICY));
243        return false;
244    }
245    return true;
246}
247
248bool MemPoolFeeRateEstimator::Write(AutoFile& file) const
249{
250    try {

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

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