Alpha release of CashDB, high-perf backend for UTXO storage

The alpha version of CashDB has been released. CashDB is a fork and the successor of Terab which has unfortunately been discontinued. CashDB is an effort (disclaimer: this is not a regular open source project, there is a BCH restriction, check the license) of Lokad to support the on-chain scaling of Bitcoin. It’s a blockchain-centric key-value store specifically tailored for the UTXO set of Bitcoin - the set of unspent transaction outputs.

With a single Intel Optane 900P card - about 400 USD at time of writing - CashDB can process close to 20,000 transactions per second, which means that a 1GB Bitcoin block can be processed in 3 min 30 or so. Thus, CashDB, in its current form, is already scalable enough to process gigabyte blocks at peak network capacity.

In practice, though, managing the UTXO set of Bitcoin is only one of the scalability challenges faced by Bitcoin. Thus, don’t expect CashDB to be a scalability silver bullet.

In order to support sustained gigabyte blocks, the throughput of CashDB is still too low, as catching-up with the network would be too slow to be practical. However, as the average volume of Visa transactions is still hovering around 2,000 transactions per second, CashDB should be enough for now.

As a storage backend for the UTXO set, CashDB is a fairly technical piece of software. CashDB is intended as a support component for full Bitcoin implementations such as Bitcoin ABC or ElectrumX. From a design perspective, CashDB is a small step toward decoupling the software parts that make Bitcoin.