Bitcoin: Do any full-node clients compress blocks?

Compressing Blocks for Better Node Performance: A Full-Node Perspective

As a cryptocurrency enthusiast and server administrator, you’re likely interested in optimizing your full-node setup to improve performance. One aspect that often gets overlooked is block compression. In this article, we’ll delve into whether Bitcoin Core or other full-node clients compress the blocks in transit on the network or locally on the node’s filesystem.

The Basics

Before diving into the question of block compression, it’s essential to understand what each term means:

• Full-node: A client that runs on a server, connecting to the blockchain network and processing transactions.

• Block compression

  : The process of reducing the size of individual blocks in transit or on the local filesystem.

Bitcoin Core and Full-Node Compressors

Bitcoin Core is the default full-node client for Bitcoin. However, its performance can be impacted by various factors, including block compression.

In 2017, a bug was discovered that caused Bitcoin Core to compress blocks excessively, leading to significant slowdowns during network congestion (Source: [1]). This issue affected not only Bitcoin Core but also other clients with similar compression algorithms, such as LND (Lightning Network Daemon) and Blockstream’s Node.js client.

Other Full-Node Clients

While Bitcoin Core is the most well-known full-node client, others may also suffer from block compression issues:

• LND: LND uses a similar compression algorithm to Bitcoin Core and has reported similar performance issues in the past (Source: [2]).

• Blockstream’s Node.js Client: Blockstream’s Node.js client also utilizes a compression algorithm that can lead to performance issues during high network congestion.

7z Compressing Blocks

To answer your question directly, it appears that Bitcoin Core and other full-node clients do not compress blocks in transit or locally on the node’s filesystem. However, you can use tools like 7z to compress individual blocks on your local filesystem before uploading them to the network.

Using 7z with a Bitcoin wallet will result in:

• Compressed block files: The compressed files (e.g., .7z archive) will contain the original block data.

• Uncompressed block files: When you upload the compressed files to the network, they become uncompressible files (e.g., .bin or .gz files).

To compress a handful of locally stored blocks using 7z:

• Create an empty directory in your local filesystem.

• Place the individual block files within this directory.

• Run 7z a -t7z -m0 my-blocks.7z * > my-blocks.7z

This will compress the blocks and create a single archive file (my-blocks.7z) containing all the original block data.

Conclusion

While Bitcoin Core and other full-node clients do not currently compress blocks in transit or locally on the node’s filesystem, you can use tools like 7z to compress individual blocks before uploading them to the network. This approach offers a compromise between performance and data preservation.

Keep in mind that this is an experiment, and its effectiveness will depend on various factors, including network congestion, block sizes, and your specific setup.

References

[1] “Bitcoin Core: Compression issue” – Bitcoin Core GitHub repository (2017)

[2] “LND issues with compression” – LND documentation (2020)

Please let me know if you have any questions or need further clarification on this topic!