08a25a7231
394e473d42coins: compact chainstate in background (Lőrinc)aa021b26f3validation: randomly compact chainstate (Lőrinc)b10889d107coins: test chainstate flush baseline (Lőrinc) Pull request description: **Problem:** https://github.com/bitcoin-core/leveldb-subtree/pull/61 disabled read-triggered seek compactions to avoid large chainstate write amplification from random UTXO lookups. That avoids repeated read-driven rewrites, but it also removes opportunistic cleanup that previously helped compact old chainstate data. After IBD, normal chainstate churn can leave obsolete entries behind until ordinary LevelDB compaction naturally reaches the affected levels, keeping the chainstate database larger than necessary. Also, chainstates created by pre-29 nodes can contain thousands of files from the old 2 MiB LevelDB table target. After the mmap limit dropped back to 1000 and seek compaction was disabled, continuing from such a chainstate can leave many table reads on the non-mmap path until the database is compacted. **Fix:** After each completed post-IBD full chainstate flush, give the chainstate a 1/320 chance to compact. With roughly hourly full flushes, this averages about once every two weeks and makes a six-month stretch without compaction about a one-in-a-million event. The randomized recurring trigger spreads compactions across nodes and keeps maintenance stateless, without storing last-compaction height or timestamp metadata in the chainstate database. Compaction runs on a background thread (`utxocompact`) so validation only schedules the work. Partially fixes #35298 and #35457 ACKs for top commit: sipa: ACK394e473d42optout21: ACK394e473d42andrewtoth: ACK394e473d42sedited: ACK394e473d42Tree-SHA512: 536a298f86ca7d87a2dd5428354b05b693931c090c7a4afd4d09b95ce53e2bd8319e01c940489a1520d8cb1010a7ea9724d2c18d2e12887bd5ec70cb68c03517
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.