From 3bb6498fb0f6ac611ba4093ef774a3152b93a2c6 Mon Sep 17 00:00:00 2001
From: Sjors Provoost <sjors@sprovoost.nl>
Date: Mon, 18 May 2026 14:17:29 +0200
Subject: [PATCH] mining: store block create options in NodeContext

Read configured mining options once during startup instead of parsing
options like -blockmaxweight each time a block template is generated.

Store the parsed startup options as BlockCreateOptions. Members left unset
keep representing unset options; hardcoded defaults are applied by
FlattenMiningOptions() before the options are used. IPC overrides and node
defaults can then be merged with the same option type used by
BlockAssembler.

Co-authored-by: Ryan Ofsky <ryan@ofsky.org>
---
 src/init.cpp                   |  3 +++
 src/node/context.h             |  7 ++++++
 src/node/interfaces.cpp        |  3 +--
 src/node/mining_args.cpp       |  2 ++
 src/rpc/mining.cpp             | 45 ++++++++++++++++++++++++++++------
 src/test/miner_tests.cpp       |  2 +-
 src/test/util/setup_common.cpp |  5 ++++
 7 files changed, 56 insertions(+), 11 deletions(-)

diff --git a/src/init.cpp b/src/init.cpp
index adf94665f59..aab7a52ebea 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -1310,6 +1310,9 @@ static ChainstateLoadResult InitAndLoadChainstate(
     if (!mempool_error.empty()) {
         return {ChainstateLoadStatus::FAILURE_FATAL, mempool_error};
     }
+    auto mining_args{node::ReadMiningArgs(args)};
+    Assert(mining_args); // no error can happen, already checked in AppInitParameterInteraction
+    node.mining_args = std::move(*mining_args);
     LogInfo("* Using %.1f MiB for in-memory UTXO set (plus up to %.1f MiB of unused mempool space)",
             cache_sizes.coins / double(1_MiB),
             mempool_opts.max_size_bytes / double(1_MiB));
diff --git a/src/node/context.h b/src/node/context.h
index 848c872fd4a..b8b3274f090 100644
--- a/src/node/context.h
+++ b/src/node/context.h
@@ -5,6 +5,8 @@
 #ifndef BITCOIN_NODE_CONTEXT_H
 #define BITCOIN_NODE_CONTEXT_H
 
+#include <node/mining_types.h>
+
 #include <atomic>
 #include <cstdlib>
 #include <functional>
@@ -81,6 +83,11 @@ struct NodeContext {
     //! Reference to chain client that should used to load or create wallets
     //! opened by the gui.
     std::unique_ptr<interfaces::Mining> mining;
+    //! Mining options used to create block templates. This value member is an
+    //! exception to the dependency guidance above because BlockCreateOptions is
+    //! a minimal dependency. It could be moved to the BlockTemplateCache
+    //! proposed in bitcoin/bitcoin#33421.
+    BlockCreateOptions mining_args;
     interfaces::WalletLoader* wallet_loader{nullptr};
     std::unique_ptr<CScheduler> scheduler;
     std::function<void()> rpc_interruption_point = [] {};
diff --git a/src/node/interfaces.cpp b/src/node/interfaces.cpp
index 5317af9ff97..5aa6e27155d 100644
--- a/src/node/interfaces.cpp
+++ b/src/node/interfaces.cpp
@@ -988,8 +988,7 @@ public:
             // Also wait during the final catch-up moments after IBD.
             if (!CooldownIfHeadersAhead(chainman(), notifications(), *maybe_tip, m_interrupt_mining)) return {};
         }
-        const auto args_options{*Assert(ReadMiningArgs(*Assert(m_node.args)))};
-        const BlockCreateOptions create_options{MergeMiningOptions(options, args_options)};
+        const BlockCreateOptions create_options{MergeMiningOptions(options, m_node.mining_args)};
         return std::make_unique<BlockTemplateImpl>(create_options,
                                                    BlockAssembler{
                                                        chainman().ActiveChainstate(),
diff --git a/src/node/mining_args.cpp b/src/node/mining_args.cpp
index 33e623a14be..ec173464bb6 100644
--- a/src/node/mining_args.cpp
+++ b/src/node/mining_args.cpp
@@ -13,10 +13,12 @@
 #include <policy/policy.h>
 #include <tinyformat.h>
 #include <util/moneystr.h>
+#include <util/result.h>
 #include <util/translation.h>
 
 #include <cstdint>
 #include <optional>
+#include <string>
 #include <utility>
 
 using common::AmountErrMsg;
diff --git a/src/rpc/mining.cpp b/src/rpc/mining.cpp
index 62e64a5427c..e89a0e61ee1 100644
--- a/src/rpc/mining.cpp
+++ b/src/rpc/mining.cpp
@@ -5,48 +5,77 @@
 
 #include <bitcoin-build-config.h> // IWYU pragma: keep
 
+#include <interfaces/mining.h>
+
+#include <addresstype.h>
+#include <arith_uint256.h>
 #include <chain.h>
 #include <chainparams.h>
 #include <chainparamsbase.h>
-#include <common/system.h>
 #include <consensus/amount.h>
 #include <consensus/consensus.h>
 #include <consensus/merkle.h>
 #include <consensus/params.h>
 #include <consensus/validation.h>
 #include <core_io.h>
-#include <deploymentinfo.h>
-#include <deploymentstatus.h>
-#include <interfaces/mining.h>
+#include <crypto/hex_base.h>
+#include <interfaces/types.h>
 #include <key_io.h>
 #include <net.h>
+#include <netbase.h>
+#include <node/blockstorage.h>
 #include <node/context.h>
 #include <node/miner.h>
 #include <node/mining_args.h>
 #include <node/mining_types.h>
 #include <node/warnings.h>
-#include <policy/ephemeral_policy.h>
+#include <policy/feerate.h>
+#include <policy/policy.h>
 #include <pow.h>
+#include <primitives/block.h>
+#include <primitives/transaction.h>
 #include <rpc/blockchain.h>
 #include <rpc/mining.h>
+#include <rpc/protocol.h>
+#include <rpc/request.h>
 #include <rpc/server.h>
 #include <rpc/server_util.h>
 #include <rpc/util.h>
 #include <script/descriptor.h>
 #include <script/script.h>
 #include <script/signingprovider.h>
+#include <serialize.h>
+#include <streams.h>
+#include <sync.h>
+#include <tinyformat.h>
 #include <txmempool.h>
+#include <uint256.h>
 #include <univalue.h>
+#include <util/chaintype.h>
+#include <util/check.h>
 #include <util/signalinterrupt.h>
 #include <util/strencodings.h>
 #include <util/string.h>
 #include <util/time.h>
-#include <util/translation.h>
 #include <validation.h>
 #include <validationinterface.h>
+#include <versionbits.h>
 
+#include <algorithm>
+#include <cstddef>
 #include <cstdint>
+#include <functional>
+#include <initializer_list>
+#include <limits>
+#include <map>
 #include <memory>
+#include <optional>
+#include <set>
+#include <span>
+#include <string>
+#include <string_view>
+#include <utility>
+#include <vector>
 
 using interfaces::BlockRef;
 using interfaces::BlockTemplate;
@@ -473,8 +502,8 @@ static RPCMethod getmininginfo()
     obj.pushKV("target", GetTarget(tip, chainman.GetConsensus().powLimit).GetHex());
     obj.pushKV("networkhashps",    getnetworkhashps().HandleRequest(request));
     obj.pushKV("pooledtx", mempool.size());
-    const auto options{node::FlattenMiningOptions(*Assert(node::ReadMiningArgs(*node.args)))};
-    obj.pushKV("blockmintxfee", ValueFromAmount(CHECK_NONFATAL(options.block_min_fee_rate)->GetFeePerK()));
+    const auto mining_options{node::FlattenMiningOptions(node.mining_args)};
+    obj.pushKV("blockmintxfee", ValueFromAmount(CHECK_NONFATAL(mining_options.block_min_fee_rate)->GetFeePerK()));
     obj.pushKV("chain", chainman.GetParams().GetChainTypeString());
 
     UniValue next(UniValue::VOBJ);
diff --git a/src/test/miner_tests.cpp b/src/test/miner_tests.cpp
index be2b5e60f6a..4d1c305311f 100644
--- a/src/test/miner_tests.cpp
+++ b/src/test/miner_tests.cpp
@@ -181,7 +181,7 @@ void MinerTestingSetup::TestPackageSelection(const CScript& scriptPubKey, const
     const auto block_package_feerates = BlockAssembler{
         m_node.chainman->ActiveChainstate(),
         &tx_mempool,
-        BlockCreateOptions{},
+        m_node.mining_args,
     }.CreateNewBlock()->m_package_feerates;
     BOOST_CHECK(block_package_feerates.size() == 2);
 
diff --git a/src/test/util/setup_common.cpp b/src/test/util/setup_common.cpp
index 09b6c9c7ddc..25d71f38550 100644
--- a/src/test/util/setup_common.cpp
+++ b/src/test/util/setup_common.cpp
@@ -26,6 +26,7 @@
 #include <node/kernel_notifications.h>
 #include <node/mempool_args.h>
 #include <node/miner.h>
+#include <node/mining_args.h>
 #include <node/peerman_args.h>
 #include <node/warnings.h>
 #include <noui.h>
@@ -65,6 +66,7 @@
 #include <future>
 #include <functional>
 #include <stdexcept>
+#include <utility>
 
 using namespace util::hex_literals;
 using node::ApplyArgsManOptions;
@@ -364,6 +366,9 @@ TestingSetup::TestingSetup(
                                                m_node.args->GetIntArg("-checkaddrman", 0));
     m_node.banman = std::make_unique<BanMan>(m_args.GetDataDirBase() / "banlist", nullptr, DEFAULT_MISBEHAVING_BANTIME);
     m_node.connman = std::make_unique<ConnmanTestMsg>(0x1337, 0x1337, *m_node.addrman, *m_node.netgroupman, Params()); // Deterministic randomness for tests.
+    auto mining_args{node::ReadMiningArgs(*m_node.args)};
+    Assert(mining_args);
+    m_node.mining_args = std::move(*mining_args);
     PeerManager::Options peerman_opts;
     ApplyArgsManOptions(*m_node.args, peerman_opts);
     peerman_opts.deterministic_rng = true;