bf77fc9cb45209b9c560208c65abc94209cd7919 [test] mempool full in package accept (glozow)
b51ebccc28e66c1822ab22d2d178be55c6618196 [validation] set PackageValidationState when mempool full (glozow)
563a2ee4f564c8ea5f8313d711b196e260568c04 [policy] disallow transactions under min relay fee, even in packages (glozow)
c4554fe894d7af8e666f5d424deccddf516713ef [test] package cpfp bumps parents <mempoolminfee but >=minrelaytxfee (glozow)
ac463e87df728689701810c3961155c49fdc5b31 [test util] mock mempool minimum feerate (glozow)
Pull request description:
Part of package relay, see #27463.
Note that this still allows packages to bump transactions that are below the dynamic mempool minimum feerate, which means this still solves the "mempool is congested and my presigned 1sat/vB tx is screwed" problem for all transactions.
On master, the package policy (only accessible through regtest-only RPC submitpackage) allows 0-fee (or otherwise below min relay feerate) transactions if they are bumped by a child. However, with default package limits, we don't yet have a DoS-resistant way of ensuring these transactions remain bumped throughout their time in the mempool. Primarily, the fee-bumping child may later be replaced by another transaction that doesn't bump the parent(s). The parent(s) could potentially stay bumped by other transactions, but not enough to ever be selected by the `BlockAssembler` (due to `blockmintxfee`).
For example, (tested [here](https://github.com/glozow/bitcoin/commits/26933-motivation)):
- The mempool accepts 24 below-minrelayfeerate transactions ("0-fee parents"), all bumped by a single high-fee transaction ("the fee-bumping child"). The fee-bumping child also spends a confirmed UTXO.
- Two additional children are added to each 0-fee parent. These children each pay a feerate slightly above the minimum relay feerate (e.g. 1.9sat/vB) such that, for each 0-fee parent, the total fees of its two children divided by the total size of the children and parent is above the minimum relay feerate.
- If a block template is built now, all transactions would be selected.
- A transaction replaces the the fee-bumping child, spending only the confirmed UTXO and not any of the outputs from the 0-fee parents.
- The 0-fee parents now each have 2 children. Their descendant feerates are above minrelayfeerate, which means that they remain in the mempool, even if the mempool evicts all below-minrelayfeerate packages.
- If a block template is built now, none of the 0-fee parents or their children would be selected.
- Even more low-feerate descendants can be added to these below-minrelayfeerate packages and they will not be evicted until they expire or the mempool reaches capacity.
Unless we have a DoS-resistant way of ensuring package CPFP-bumped transactions are always bumped, allowing package CPFP to bump below-minrelayfeerate transactions can result in these problematic situations. See #27018 which proposes a partial solution with some limitations, and contains discussion about potential improvements to eviction strategy. While no adequate solution exists, for now, avoid these situations by requiring all transactions to meet min relay feerate.
ACKs for top commit:
ajtowns:
reACK bf77fc9cb45209b9c560208c65abc94209cd7919
instagibbs:
re-ACK bf77fc9cb4
Tree-SHA512: 28940f41493a9e280b010284316fb8caf1ed7b2090ba9a4ef8a3b2eafc5933601074b142f4f7d4e3c6c4cce99d3146f5c8e1393d9406c6f2070dd41c817985c9
Bitcoin Core
Setup
Bitcoin Core is the original Bitcoin client and it builds the backbone of the network. It downloads and, by default, stores the entire history of Bitcoin transactions, which requires a few hundred gigabytes of disk space. Depending on the speed of your computer and network connection, the synchronization process can take anywhere from a few hours to a day or more.
To download Bitcoin Core, visit bitcoincore.org.
Running
The following are some helpful notes on how to run Bitcoin Core on your native platform.
Unix
Unpack the files into a directory and run:
bin/bitcoin-qt
(GUI) orbin/bitcoind
(headless)
Windows
Unpack the files into a directory, and then run bitcoin-qt.exe.
macOS
Drag Bitcoin Core to your applications folder, and then run Bitcoin Core.
Need Help?
- See the documentation at the Bitcoin Wiki for help and more information.
- Ask for help on Bitcoin StackExchange.
- Ask for help on #bitcoin on Libera Chat. If you don't have an IRC client, you can use web.libera.chat.
- Ask for help on the BitcoinTalk forums, in the Technical Support board.
Building
The following are developer notes on how to build Bitcoin Core on your native platform. They are not complete guides, but include notes on the necessary libraries, compile flags, etc.
- Dependencies
- macOS Build Notes
- Unix Build Notes
- Windows Build Notes
- FreeBSD Build Notes
- OpenBSD Build Notes
- NetBSD Build Notes
- Android Build Notes
Development
The Bitcoin repo's root README contains relevant information on the development process and automated testing.
- Developer Notes
- Productivity Notes
- Release Process
- Source Code Documentation (External Link)
- Translation Process
- Translation Strings Policy
- JSON-RPC Interface
- Unauthenticated REST Interface
- Shared Libraries
- BIPS
- Dnsseed Policy
- Benchmarking
- Internal Design Docs
Resources
- Discuss on the BitcoinTalk forums, in the Development & Technical Discussion board.
- Discuss project-specific development on #bitcoin-core-dev on Libera Chat. If you don't have an IRC client, you can use web.libera.chat.
Miscellaneous
- Assets Attribution
- bitcoin.conf Configuration File
- CJDNS Support
- Files
- Fuzz-testing
- I2P Support
- Init Scripts (systemd/upstart/openrc)
- Managing Wallets
- Multisig Tutorial
- P2P bad ports definition and list
- PSBT support
- Reduce Memory
- Reduce Traffic
- Tor Support
- Transaction Relay Policy
- ZMQ
License
Distributed under the MIT software license.