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

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bitcoin / bitcoinstable

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▤ block_policy_estimator.cpp

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▤ estimator_man.cppGuide

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▤ mempool_estimator.h

▤ ephemeral_policy.cppGuide

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bitcoin / src / policy / fees / mempool_estimator.cpp

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251        LOCK(cs);
252        file << CURRENT_MEMPOOL_ESTIMATOR_VERSION;
253        file << Using<VectorFormatter<MinedBlockStatsFormatter>>(m_prev_mined_blocks);
254        file << m_mined_blocks_tip_hash;
255    } catch (const std::exception&) {
256        return false;
257    }
258    return true;
259}
260
261void MemPoolFeeRateEstimator::FlushMinedBlockStats()
262{
263    if (!m_mempool_estimator_file_path.parent_path().empty()) {
264        std::error_code error;
265        fs::create_directories(m_mempool_estimator_file_path.parent_path(), error);
266        if (error) {
267            LogWarning("%s: failed to create mempool policy estimator directory %s: %s. Continuing anyway",
268                       FeeRateEstimatorTypeToString(FeeRateEstimatorType::MEMPOOL_POLICY),
269                       fs::PathToString(m_mempool_estimator_file_path.parent_path()), error.message());
270            return;
271        }
272    }
273    AutoFile file{fsbridge::fopen(m_mempool_estimator_file_path, "wb")};
274    if (file.IsNull()) {
275        LogWarning("%s: unable to open %s for writing. Continuing anyway",
276                   FeeRateEstimatorTypeToString(FeeRateEstimatorType::MEMPOOL_POLICY),
277                   fs::PathToString(m_mempool_estimator_file_path));
278        return;
279    }
280    if (!Write(file)) {
281        LogWarning("%s: Unable to write mined-block stats to %s (non-fatal)",
282                   FeeRateEstimatorTypeToString(FeeRateEstimatorType::MEMPOOL_POLICY),
283                   fs::PathToString(m_mempool_estimator_file_path));
284    }
285    if (file.fclose() != 0) {
286        LogWarning("Failed to close mempool policy estimator file %s: %s. Continuing anyway.",
287                   fs::PathToString(m_mempool_estimator_file_path), SysErrorString(errno));
288        return;
289    }
290    LogDebug(BCLog::ESTIMATEFEE, "%s: mined-block stats flushed to %s.",
291             FeeRateEstimatorTypeToString(FeeRateEstimatorType::MEMPOOL_POLICY),
292             fs::PathToString(m_mempool_estimator_file_path));
293}
294
295void MemPoolFeeRateEstimator::MempoolLoadFailed()
296{
297    LOCK(cs);
298    if (m_prev_mined_blocks.empty()) return;
299    LogDebug(BCLog::ESTIMATEFEE, "%s: mempool did not load; clearing mined-block stats",
300             FeeRateEstimatorTypeToString(FeeRateEstimatorType::MEMPOOL_POLICY));
301    m_prev_mined_blocks.clear();
302}
303
304void MemPoolFeeRateEstimator::MempoolTxsRemovedForBlock(const std::shared_ptr<const CBlock>& block,
305                                                        const std::vector<RemovedMempoolTransactionInfo>& txs_removed_for_block,
306                                                        unsigned int block_height)
307{
308    LOCK(cs);
309    Assert(!block->vtx.empty());
310    // Accumulate total block weight and removed mempool tx weight, both excluding the coinbase.
311    const auto get_tx_weight = [](const CTransactionRef& tx) {
312        return static_cast<uint64_t>(GetTransactionWeight(*tx));
313    };
314    // Skip vtx[0], which is the coinbase.
315    const uint64_t block_weight = std::accumulate(std::next(block->vtx.begin()), block->vtx.end(), uint64_t{0},
316                                                  [&](uint64_t acc, const CTransactionRef& tx) {
317                                                      return acc + get_tx_weight(tx);
318                                                  });
319    const uint64_t removed_weight = std::accumulate(
320        txs_removed_for_block.begin(), txs_removed_for_block.end(), uint64_t{0},
321        [&](uint64_t acc, const RemovedMempoolTransactionInfo& tx) {
322            return acc + get_tx_weight(tx.info.m_tx);
323        });
324    AddMinedBlockStats(m_prev_mined_blocks, {block_height, removed_weight, block_weight});
325    m_mined_blocks_tip_hash = block->GetHash();
326    m_cache.Clear();
327}
328
329// Require at least one block worth of activity across the window before using
330// the coverage ratio as a representative mempool health signal.
331static constexpr uint64_t MIN_REPRESENTATIVE_WINDOW_WEIGHT{DEFAULT_BLOCK_MAX_WEIGHT};
332
333MemPoolFeeRateEstimator::MempoolHealth MemPoolFeeRateEstimator::GetMempoolHealth() const
334{
335    LOCK(cs);
336    const auto estimator_name{FeeRateEstimatorTypeToString(FeeRateEstimatorType::MEMPOOL_POLICY)};
337    if (m_prev_mined_blocks.size() < MEMPOOL_HEALTH_WINDOW_BLOCKS) {
338        LogDebug(BCLog::ESTIMATEFEE, "%s: mempool health check failed; tracked_blocks=%s required_blocks=%s",
339                 estimator_name, m_prev_mined_blocks.size(), MEMPOOL_HEALTH_WINDOW_BLOCKS);
340        return MempoolHealth::INSUFFICIENT_DATA;
341    }
342    uint64_t total_block_weight{0};
343    uint64_t total_removed_weight{0};
344    uint64_t expected_height{m_prev_mined_blocks.front().m_height};
345    for (const auto& block : m_prev_mined_blocks) {
346        Assume(block.m_height == expected_height);
347        ++expected_height;
348        total_block_weight += block.m_block_weight;
349        total_removed_weight += block.m_removed_block_txs_weight;
350    }
351    // Too little block activity for the coverage ratio to be meaningful; skip it.
352    if (total_block_weight < MIN_REPRESENTATIVE_WINDOW_WEIGHT) {
353        LogDebug(BCLog::ESTIMATEFEE, "%s: mempool health check passed; low activity, total_block_weight=%s minimum=%s",
354                 estimator_name, total_block_weight, MIN_REPRESENTATIVE_WINDOW_WEIGHT);
355        return MempoolHealth::HEALTHY;
356    }
357    const double representation_ratio = static_cast<double>(total_removed_weight) / total_block_weight;
358    LogDebug(BCLog::ESTIMATEFEE,
359             "%s: mempool health check %s; removed_weight=%s total_block_weight=%s "
360             "coverage=%.2f required_coverage=%.2f",
361             estimator_name,
362             representation_ratio >= MEMPOOL_REPRESENTATION_THRESHOLD ? "passed" : "failed",
363             total_removed_weight,
364             total_block_weight,
365             representation_ratio,
366             MEMPOOL_REPRESENTATION_THRESHOLD);
367    return representation_ratio >= MEMPOOL_REPRESENTATION_THRESHOLD ? MempoolHealth::HEALTHY : MempoolHealth::LOW_COVERAGE;
368}
369
370util::Expected<FeeRateEstimation, FeeRateEstimationError> MemPoolFeeRateEstimator::EstimateFeeRate(bool conservative) const
371{
372    constexpr auto estimator_type{FeeRateEstimatorType::MEMPOOL_POLICY};
373    if (!m_mempool.GetLoadTried()) {
374        return EstimationError(strprintf("%s: Mempool not loaded yet, no fee rate estimate available", FeeRateEstimatorTypeToString(estimator_type)));
375    }
376    if (auto error{MempoolHealthError(GetMempoolHealth())}) {
377        return EstimationError(strprintf("%s: %s", FeeRateEstimatorTypeToString(estimator_type), *error));
378    }
379    // The estimator lock is not held while building a block template, so
380    // in a rare edge case concurrent callers may duplicate work.
381    //
382    // Cached fee rate estimates are tagged with the chain tip they were computed on
383    // and only served from the cache while that tip is current.
384    //
385    // The fee rate estimate returned directly below may still reflect a tip that went
386    // stale during the call; that is an accepted tradeoff of not holding
387    // locks across block assembly.
388    {
389        const uint256 tip_hash{WITH_LOCK(::cs_main, return Assume(m_chainman.CurrentChainstate().m_chain.Tip())->GetBlockHash())};
390        LOCK(cs);
391        const auto cached_estimate = m_cache.GetCachedEstimate(tip_hash);
392        if (cached_estimate) {
393            const auto cached_feerate{
394                conservative ? cached_estimate->m_conservative : cached_estimate->m_economical};
395            return FeeRateEstimation{estimator_type, cached_feerate, MEMPOOL_FEE_ESTIMATOR_MAX_TARGET};
396        }
397    }
398    node::BlockCreateOptions options;
399    options.test_block_validity = false;
400    const auto blocktemplate = WITH_LOCK(::cs_main, return (node::BlockAssembler{m_chainman.CurrentChainstate(), &m_mempool, options}).CreateNewBlock());
401    if (!blocktemplate) return EstimationError(strprintf("%s: Failed to create block template for fee rate estimation", FeeRateEstimatorTypeToString(estimator_type)));
402    // Sort again because the rounding up when converting from weight to vsize may cause slight misorder.
403    std::sort(blocktemplate->m_package_feerates.begin(), blocktemplate->m_package_feerates.end(), [](const auto& a, const auto& b) { return ByRatio{a} > ByRatio{b}; });
404    const auto percentiles = CalculateMaxWeightPercentiles(blocktemplate->m_package_feerates);
405    // Fall back to a relayable floor (the higher of the min relay fee and the current
406    // mempool min fee) for any percentile the mempool was too sparse to fill.
407    const FeePerVSize floor{std::max(m_mempool.m_opts.min_relay_feerate, m_mempool.GetMinFee()).GetFeePerVSize()};
408    const FeePerVSize p50{percentiles.p50.IsEmpty() ? floor : percentiles.p50};
409    const FeePerVSize p75{percentiles.p75.IsEmpty() ? floor : percentiles.p75};
410    WITH_LOCK(cs, m_cache.Update(p50, p75, blocktemplate->block.hashPrevBlock));
411    LogDebug(BCLog::ESTIMATEFEE, "%s: conservative/economical fee rate: %s/%s %s/kvB",
412             FeeRateEstimatorTypeToString(estimator_type), CFeeRate(p50).GetFeePerK(),
413             CFeeRate(p75).GetFeePerK(), CURRENCY_ATOM);
414    return FeeRateEstimation{estimator_type, conservative ? p50 : p75, MEMPOOL_FEE_ESTIMATOR_MAX_TARGET};
415}
416

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440 guided files · 2,580 pending. Guides cover key sections, not every line.

cmake/bitcoin-build-config.h.in src/consensus/amount.h src/consensus/consensus.h src/primitives/block.h src/primitives/transaction.h src/crypto/sha256.h src/util/moneystr.h src/clientversion.h src/uint256.h src/script/script.h src/policy/policy.h CMakeLists.txt README.md COPYING src/consensus/tx_check.cpp src/consensus/tx_verify.cpp src/consensus/merkle.cpp src/pow.cpp src/validation.cpp src/script/interpreter.cpp src/script/solver.cpp src/script/sign.cpp src/key_io.cpp src/net.cpp src/net_processing.cpp src/netaddress.cpp src/protocol.h src/wallet/wallet.cpp src/wallet/spend.cpp

← Previous 250 linesCode page 2

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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