b5fea8d0cc
This adds a new CuckooCache in validation, caching whether all of a transaction's scripts were valid with a given set of script flags. Unlike previous attempts at caching an entire transaction's validity, which have nearly universally introduced consensus failures, this only caches the validity of a transaction's scriptSigs. As these are pure functions of the transaction and data it commits to, this should be much safer. This is somewhat duplicative with the sigcache, as entries in the new cache will also have several entries in the sigcache. However, the sigcache is kept both as ATMP relies on it and because it prevents malleability-based DoS attacks on the new higher-level cache. Instead, the -sigcachesize option is re-used - cutting the sigcache size in half and using the newly freed memory for the script execution cache. Transactions which match the script execution cache never even have entries in the script check thread's workqueue created. Note that the cache is indexed only on the script execution flags and the transaction's witness hash. While this is sufficient to make the CScriptCheck() calls pure functions, this introduces dependancies on the mempool calculating things such as the PrecomputedTransactionData object, filling the CCoinsViewCache, etc in the exact same way as ConnectBlock. I belive this is a reasonable assumption, but should be noted carefully. In a rather naive benchmark (reindex-chainstate up to block 284k with cuckoocache always returning true for contains(), -assumevalid=0 and a very large dbcache), this connected blocks ~1.7x faster. |
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| .github | ||
| .tx | ||
| build-aux/m4 | ||
| contrib | ||
| depends | ||
| doc | ||
| share | ||
| src | ||
| test | ||
| .gitattributes | ||
| .gitignore | ||
| .travis.yml | ||
| autogen.sh | ||
| configure.ac | ||
| CONTRIBUTING.md | ||
| COPYING | ||
| INSTALL.md | ||
| libbitcoinconsensus.pc.in | ||
| Makefile.am | ||
| README.md | ||
Bitcoin Core integration/staging tree
What is Bitcoin?
Bitcoin is an experimental digital currency that enables instant payments to anyone, anywhere in the world. Bitcoin uses peer-to-peer technology to operate with no central authority: managing transactions and issuing money are carried out collectively by the network. Bitcoin Core is the name of open source software which enables the use of this currency.
For more information, as well as an immediately useable, binary version of the Bitcoin Core software, see https://bitcoin.org/en/download, or read the original whitepaper.
License
Bitcoin Core is released under the terms of the MIT license. See COPYING for more information or see https://opensource.org/licenses/MIT.
Development Process
The master branch is regularly built and tested, but is not guaranteed to be
completely stable. Tags are created
regularly to indicate new official, stable release versions of Bitcoin Core.
The contribution workflow is described in CONTRIBUTING.md.
The developer mailing list should be used to discuss complicated or controversial changes before working on a patch set.
Developer IRC can be found on Freenode at #bitcoin-core-dev.
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 in configure) with: make check. Further details on running
and extending unit tests can be found in /src/test/README.md.
There are also regression and integration tests, written
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These tests can be run (if the test dependencies are installed) with: test/functional/test_runner.py
The Travis CI system makes sure that every pull request is built for Windows, Linux, and OS X, and that unit/sanity tests are run automatically.
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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
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