merge-script d3056bc149
Merge bitcoin/bitcoin#34606: doc: clarify swapping impact on IBD performance
a61907e5d9c1988eb1e018cae5831d6b94f4da7f doc: explain swapping in `reduce-memory.md` (Lőrinc)

Pull request description:

  ### Problem
  Sustained [heavy swapping](https://en.wikipedia.org/wiki/Thrashing_(computer_science)) can grind execution to a halt, but today users get no direct warning from the node when this happens, and this caveat is not documented.

  ### Fix
  We can’t easily detect heavy swap pressure in a reliable, cross-platform way, but we can document what swapping is and why it can severely degrade IBD performance.

  ---

  Note: An earlier version of this PR attempted to detect and warn on heavy swapping (Linux-only), but it was changed to documentation based on review feedback.

ACKs for top commit:
  ajtowns:
    utACK a61907e5d9c1988eb1e018cae5831d6b94f4da7f
  sedited:
    ACK a61907e5d9c1988eb1e018cae5831d6b94f4da7f

Tree-SHA512: b21c40d07d78d890c19d3a17faad4ab4127688884dc433a1bdb63d18de07628c048227eba2f1258c6b542a71a986d4250f8abf8f8ffe0cda433ce0c8673978d4
2026-03-09 14:21:36 +00:00
2026-02-06 13:40:59 +00:00
2026-03-03 17:04:56 +00:00
2025-12-29 17:50:43 +00:00
2025-06-19 11:22:14 +01:00

Bitcoin Core integration/staging tree

https://bitcoincore.org

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.

Description
Bitcoin Core integration/staging tree
Readme 2.5 GiB
Languages
C++ 64.5%
Python 18.9%
C 12.9%
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