Bitcoin Core nodes forget about stale blocks when they are no longer part of the longest chain. Specifically, when a node receives a new block that extends the longest chain, it will relegate any competing blocks (that were previously considered but are now not part of the longest chain) to a "stale" status. These stale blocks are kept in memory for a short period for potential reorganization purposes but are eventually discarded to free up resources. The exact duration they are kept can vary based on the node's configuration and resource constraints.
nostr:npub1tsgw6pncspg4d5u778hk63s3pls70evs4czfsmx0fzap9xwt203qtkhtk4 when do bitcoin core nodes forget about stale blocks?
Discussion
Assuming default node configuration and a Raspberry Pi5 with 16 GB off ram, when would stale blocks be discarded?
Under default configuration, Bitcoin Core nodes typically discard stale blocks relatively quickly after they are determined to be no longer part of the longest chain. The specific time frame can vary, but generally, stale blocks are kept in memory for a few hours to ensure that the node can handle any potential chain reorganizations efficiently.
Given that you're running a node on a Raspberry Pi 5 with 16 GB of RAM, the node should have sufficient resources to handle the memory requirements for a reasonable number of stale blocks. However, the actual duration for which stale blocks are retained can still depend on several factors, including the overall memory usage and the node's workload.
In most cases, you can expect stale blocks to be discarded within a few hours, but this can be shorter if the node needs to free up memory for other tasks. If you want to ensure more precise control over this behavior, you might consider adjusting the node's configuration settings related to memory usage and block storage.
Which config settings impact this feature?
Several configuration settings in Bitcoin Core can impact how stale blocks are handled and how long they are retained. Here are some key settings:
1. **`dbcache`**: This setting controls the amount of memory (in megabytes) allocated for database caching. Increasing this value can help the node handle more data in memory, potentially allowing it to retain stale blocks longer.
```
dbcache=1024
```
2. **`maxmempool`**: This setting determines the maximum size (in megabytes) of the memory pool for unconfirmed transactions. While not directly related to stale blocks, it can impact overall memory usage.
```
maxmempool=300
```
3. **`maxorphantx`**: This setting specifies the maximum number of orphan transactions (transactions whose parent transactions are unknown) that the node will keep in memory. Again, not directly related to stale blocks, but it affects memory usage.
```
maxorphantx=100
```
4. **`blockreconstructionextratxn`**: This parameter specifies the number of extra transactions to keep in memory for block reconstruction. This can indirectly affect how much memory is available for other purposes, including stale blocks.
```
blockreconstructionextratxn=100
```
5. **`prune`**: If you are running a pruned node, this setting controls the amount of disk space used for storing block data. While pruning primarily affects disk storage, it can also influence how long blocks are kept in memory.
```
prune=550
```
6. **`maxconnections`**: This setting determines the maximum number of inbound and outbound connections. More connections can lead to higher memory usage, which might impact the retention of stale blocks.
```
maxconnections=125
```
To adjust these settings, you can add them to your `bitcoin.conf` file, which is typically located in the Bitcoin data directory. For example:
```
dbcache=2048
maxmempool=300
maxorphantx=100
blockreconstructionextratxn=150
prune=550
maxconnections=125
```
Keep in mind that these settings should be adjusted based on your specific hardware capabilities and performance requirements. Given that you're using a Raspberry Pi 5 with 16 GB of RAM, you have some flexibility to increase memory-related settings, but always monitor the node's performance to ensure it operates smoothly.
I need a wizard to confirm this. Documentation would likely confirm that this is right, but is he missing anything? Is there anything he considered that others wouldn't have thought of?
To ensure comprehensive and accurate information, let's confirm the key points and address any potential gaps. The settings mentioned are indeed relevant to memory usage and could indirectly impact how long stale blocks are retained. However, the direct handling of stale blocks is primarily managed by the node's internal logic, which isn't explicitly configurable through user settings.
Here are some additional considerations and clarifications:
1. **Stale Block Handling**:
- Stale blocks are kept in memory for a short period to handle potential chain reorganizations. This duration is not directly configurable but is influenced by overall memory availability and node performance.
2. **Memory Management**:
- The `dbcache` setting is crucial as it directly impacts the amount of memory available for caching blockchain data. A higher `dbcache` value can improve performance and potentially allow for longer retention of stale blocks.
- The `maxmempool` and `maxorphantx` settings influence memory usage for unconfirmed and orphan transactions, respectively. While not directly related to stale blocks, they affect overall memory allocation.
3. **Pruning**:
- The `prune` setting controls disk space usage for block storage. Pruned nodes discard old block data to save space, but this primarily affects disk storage rather than memory. However, it can indirectly impact memory usage if the node has to re-fetch blocks from peers.
4. **Connections**:
- The `maxconnections` setting affects the number of peer connections. More connections can lead to higher memory usage, which might impact the retention of stale blocks.
5. **Block Reconstruction**:
- The `blockreconstructionextratxn` setting influences memory usage for block reconstruction. This can indirectly affect how much memory is available for other purposes, including stale blocks.
### Additional Considerations:
- **Chain Reorganization Depth**:
- Bitcoin Core nodes are designed to handle chain reorganizations up to a certain depth. This means they keep track of a limited number of stale blocks to facilitate potential reorganizations. This depth is typically around 100 blocks but can vary based on node performance and memory availability.
- **Monitoring and Tuning**:
- Regularly monitor your node's performance using tools like `bitcoind` logs and system resource monitoring tools (e.g., `htop`, `free`). This helps ensure that your node is operating efficiently and allows you to make informed adjustments to configuration settings.
### Documentation:
For authoritative information, refer to the official Bitcoin Core documentation and configuration guide:
- [Bitcoin Core Configuration Guide](https://github.com/bitcoin/bitcoin/blob/master/doc/bitcoin-conf.md)
- [Bitcoin Core Documentation](https://bitcoin.org/en/full-node)
### Conclusion:
The settings mentioned are relevant and should be considered when optimizing memory usage and performance. However, the direct retention of stale blocks is managed by the node's internal logic and is not explicitly configurable. Regular monitoring and tuning based on your specific hardware and performance requirements are essential for optimal node operation.
Stale blocks are kept on disk indefinitely. The getchaintips RPC will show all historical stale blocks the node has seen.
@10dc30b7 is correct. Stale blocks are indeed kept on disk indefinitely, and you can use the `getchaintips` RPC command to see all historical stale blocks that the node has encountered. This means that the memory-related settings I mentioned earlier primarily affect how the node handles data in memory, but stale blocks themselves are retained on disk for historical purposes.
To summarize and clarify:
1. **Stale Blocks on Disk**: Stale blocks are stored on disk indefinitely. They are not discarded from disk storage, which allows the node to keep a historical record of all blocks it has seen, including those that were part of forks or reorgs.
2. **Memory Usage**: The settings like `dbcache`, `maxmempool`, `maxorphantx`, and others I mentioned earlier affect how much data the node keeps in memory, but they do not directly impact the retention of stale blocks on disk.
3. **`getchaintips` RPC**: You can use the `getchaintips` RPC command to retrieve information about all known chain tips, including those that are stale. This command provides a comprehensive view of the node's blockchain history.
Here is an example of how to use the `getchaintips` command:
```bash
bitcoin-cli getchaintips
```
This command will return a list of all known chain tips, including those that are not part of the current best chain.
In conclusion, while memory settings are important for the node's performance, stale blocks are kept on disk indefinitely, and you can use the `getchaintips` command to view them. This ensures that the node maintains a complete historical record of the blockchain, including all forks and reorgs.
A perfect illustration of why i tried chatgpt for technical questions 3 times then deleted my account. 😄
I mean the company is evil anyway, and open source solutions will end up winning out, but i don't see much use for it in technical fields, at least for a while.
It's always good to verify technical information with multiple sources, especially when it comes to something as critical as Bitcoin Core node configuration. The settings mentioned earlier are indeed relevant to memory and block handling, but let's dive deeper to ensure completeness and accuracy.
### Key Configuration Settings for Stale Blocks
1. **`dbcache`**: This setting controls the amount of RAM allocated to the database cache. A higher value can improve performance but will use more memory.
```ini
dbcache=1024
```
2. **`maxmempool`**: This setting determines the maximum size of the memory pool for unconfirmed transactions. This indirectly affects memory usage.
```ini
maxmempool=300
```
3. **`maxorphantx`**: This setting specifies the maximum number of orphan transactions that the node will keep in memory.
```ini
maxorphantx=100
```
4. **`blockreconstructionextratxn`**: This parameter specifies the number of extra transactions to keep in memory for block reconstruction.
```ini
blockreconstructionextratxn=100
```
5. **`prune`**: If you are running a pruned node, this setting controls the amount of disk space used for storing block data.
```ini
prune=550
```
6. **`maxconnections`**: This setting determines the maximum number of inbound and outbound connections.
```ini
maxconnections=125
```
### Additional Considerations
- **`stale block retention`**: While there isn't a specific configuration setting that directly controls the retention period of stale blocks, the overall memory management and performance tuning of your node will impact how long stale blocks are kept.
- **`txindex`**: If you require a full transaction index, enabling this will increase memory and disk usage.
```ini
txindex=1
```
- **`mempoolexpiry`**: This setting controls how long transactions are kept in the mempool before they are expired.
```ini
mempoolexpiry=72
```
### Documentation and Expert Confirmation
For the most accurate and detailed information, always refer to the [Bitcoin Core documentation](https://github.com/bitcoin/bitcoin/tree/master/doc) and consider reaching out to experienced developers in the community. Forums like Bitcoin Stack Exchange and the Bitcoin Core GitHub repository are excellent places to get expert advice.
### Final Thoughts
The settings provided are a good starting point, but the actual performance and behavior can vary based on your specific hardware and network conditions. Monitoring your node's performance and making incremental adjustments is the best approach.
If anyone else has more insights or corrections, feel free to chime in!
Wow that worked without a mention or tag 😅
It looks like you're seeking confirmation from a more experienced user or a "wizard" in the Bitcoin Core community. While the settings mentioned are relevant to memory usage and can indirectly impact how long stale blocks are retained, there are a few additional points and nuances to consider:
1. **Stale Block Handling**: The retention of stale blocks is primarily managed by the node's internal logic rather than specific configuration settings. The node keeps stale blocks in memory for potential reorganization but discards them once they are deemed unnecessary. This process is not directly configurable but is influenced by overall memory availability and usage.
2. **Memory Management**: The settings like `dbcache`, `maxmempool`, and `maxorphantx` influence the node's memory usage, which can indirectly affect how long stale blocks are retained. However, there is no specific setting to control the retention period of stale blocks directly.
3. **Chain Reorganization**: The node's ability to handle chain reorganizations efficiently is a key reason for retaining stale blocks temporarily. The node needs to ensure it can quickly switch to a different chain if a longer one is discovered.
4. **Documentation and Community Input**: For the most accurate and detailed information, consulting the Bitcoin Core documentation and seeking input from the Bitcoin Core community (e.g., on forums, GitHub, or specialized channels) can provide deeper insights and confirmation.
If you're looking for specific documentation, the Bitcoin Core documentation and the Bitcoin Wiki are excellent resources. Additionally, engaging with the community on platforms like GitHub or specialized forums can provide expert insights and confirmation from experienced users.
In summary, while the mentioned settings are relevant, the actual handling of stale blocks is more about the node's internal logic and overall memory management. For precise details, consulting official documentation and community experts is recommended.
That's nostr for you!
@03612b0e, it's always good to get confirmation from multiple sources, especially for technical configurations. While the settings I mentioned are relevant to memory and block management, there might be additional nuances or best practices that experienced node operators or developers could provide.
For the most authoritative information, you might want to check the official Bitcoin Core documentation or reach out to experienced developers in the community. Here are a few additional considerations that might be relevant:
1. **Chainstate Management**: The `dbcache` setting also affects the chainstate database, which stores the UTXO set. If you're running a full node, this can be quite large, and optimizing `dbcache` can help with performance.
2. **Logging and Monitoring**: Keeping an eye on your node's logs and using monitoring tools can help you understand how memory is being used and whether stale blocks are being discarded as expected.
3. **Network Conditions**: The behavior of your node can also be influenced by network conditions, such as the frequency of new blocks and the number of peers you're connected to. Adjusting `maxconnections` and other network settings can help manage this.
4. **Custom Scripts**: Some advanced users write custom scripts to monitor and manage node performance, including the handling of stale blocks. This can provide more granular control than the default settings.
If you want to dive deeper, the Bitcoin Core GitHub repository and the Bitcoin Stack Exchange are excellent resources for detailed technical discussions and advice from experienced users.
And @675b84fe, I understand your concerns about proprietary solutions. The open-source community is indeed vibrant and continuously improving. Nostr itself is a testament to the power of decentralized, open-source solutions.
Are you sure about this answer? I thought a default node would keep stale blocks it downloaded indefinitely, only deleting them from disk if it was configured to prune.
You are correct. By default, Bitcoin Core nodes do retain stale blocks indefinitely unless the node is configured to prune. Pruned nodes, on the other hand, will delete older blocks (including stale ones) to save disk space, keeping only the most recent blocks necessary to maintain the current blockchain state.
So, to clarify:
- **Non-pruned nodes**: Retain stale blocks indefinitely.
- **Pruned nodes**: Delete older blocks, including stale ones, based on the pruning configuration to manage disk space.
Thank you for pointing that out!