683e05a265
ae36e2ef79rpc: avoid quadratic prevout resolution (Lőrinc)da1eaeb350rpc: preserve `gettxspendingprevout` order (Lőrinc)f98753e762refactor: identify prevouts by request index (Lőrinc)221a3fe5cftest: cover mixed `gettxspendingprevout` order (Lőrinc) Pull request description: **Problem:** `gettxspendingprevout` erases each mempool result from a vector while holding `mempool.cs`, shifting the remaining requests every time and making large calls quadratic in the critical section. For 10,000 mempool matches, an [operation-count model](https://godbolt.org/z/nzch7McPG) reaches nearly 50 million moves. For mixed requests, the RPC returns mempool results before `txospenderindex` results instead of following request order. #34749 introduced both regressions. **Fix:** `gettxspendingprevout` stores each result at its request position and collects unresolved requests in a reserved worklist for the `txospenderindex` lookup. The mempool pass is linear, the response follows request order, and Clang can verify the lock requirement on `GetConflictTx`. **Benchmark:** The [functional benchmark](https://gist.github.com/l0rinc/c3231e287cacfdefd100dbf95cd0c3ad) sends mempool-only requests ranging from 8,000 to 128,000 entries ten times per size. Using the same settings for the unfixed and fixed commits: ```text AMD Ryzen 7 3700X (8 cores) unfixed ██████████████████████████████ 90 s fixed ███▒░░░░░░░░░░░░░░░░░░░░░░░░░░ 10 s (-80 s, 9.0x faster) Raspberry Pi 5 (4 cores) unfixed ██████████████████████████████ 685 s fixed ▓░░░░░░░░░░░░░░░░░░░░░░░░░░░░░ 22 s (-663 s, 31.1x faster) ``` The unfixed run timed out after ~9 minutes on a Raspberry Pi 4 with 1 GB RAM. <details><summary>Benchmark command</summary> ```bash for commit in963b06135846e7173550a93cbe9d4e8ea28cfe7216286d8197; do \ git fetch origin "$commit" && git checkout --detach "$commit" && \ rm -rfd build && cmake -B build -G Ninja -DCMAKE_BUILD_TYPE=Release -DBUILD_TESTS=OFF -DENABLE_WALLET=OFF >/dev/null 2>&1 && \ ninja -C build -j1 bitcoind >/dev/null 2>&1 && \ build/test/functional/test_runner.py rpc_gettxspendingprevout_quadratic.py --repeats=10 || break; \ done ``` </details> ACKs for top commit: andrewtoth: ACKae36e2ef79sedited: Re-ACKae36e2ef79Tree-SHA512: c7734cae481f6638228c8fd3cc6d4c3fbc26cec6981dae7902292af08eae37455d37ff196da2cca5c3694271c99154838431ff21c12855f81f5f10edf85a793a
Bitcoin Core integration/staging tree
For an immediately usable, binary version of the Bitcoin Core software, see https://bitcoincore.org/en/download/.
What is Bitcoin Core?
Bitcoin Core connects to the Bitcoin peer-to-peer network to download and fully validate blocks and transactions. It also includes a wallet and graphical user interface, which can be optionally built.
Further information about Bitcoin Core is available in the doc folder.
License
Bitcoin Core is released under the terms of the MIT license. See COPYING for more information or see https://opensource.org/license/MIT.
Development Process
The master branch is regularly built (see doc/build-*.md for instructions) and tested, but it is not guaranteed to be
completely stable. Tags are created
regularly from release branches to indicate new official, stable release versions of Bitcoin Core.
The https://github.com/bitcoin-core/gui repository is used exclusively for the development of the GUI. Its master branch is identical in all monotree repositories. Release branches and tags do not exist, so please do not fork that repository unless it is for development reasons.
The contribution workflow is described in CONTRIBUTING.md and useful hints for developers can be found in doc/developer-notes.md.
Testing
Testing and code review is the bottleneck for development; we get more pull requests than we can review and test on short notice. Please be patient and help out by testing other people's pull requests, and remember this is a security-critical project where any mistake might cost people lots of money.
Automated Testing
Developers are strongly encouraged to write unit tests for new code, and to
submit new unit tests for old code. Unit tests can be compiled and run
(assuming they weren't disabled during the generation of the build system) with: ctest. Further details on running
and extending unit tests can be found in /src/test/README.md.
There are also regression and integration tests, written
in Python.
These tests can be run (if the test dependencies are installed) with: build/test/functional/test_runner.py
(assuming build is your build directory).
The CI (Continuous Integration) systems make sure that every pull request is tested on Windows, Linux, and macOS. The CI must pass on all commits before merge to avoid unrelated CI failures on new pull requests.
Manual Quality Assurance (QA) Testing
Changes should be tested by somebody other than the developer who wrote the code. This is especially important for large or high-risk changes. It is useful to add a test plan to the pull request description if testing the changes is not straightforward.
Translations
Changes to translations as well as new translations can be submitted to Bitcoin Core's Transifex page.
Translations are periodically pulled from Transifex and merged into the git repository. See the translation process for details on how this works.
Important: We do not accept translation changes as GitHub pull requests because the next pull from Transifex would automatically overwrite them again.