The Purge will introduce history expiration via EIP-4444 to limit the amount of historical data stored.
Ethereum co-founder Vitalik Buterin has shared the next steps for protocol simplification and node resource load decreases, known as the Purge.
The Purge is a key stage in the Ethereum transition that involves the removal of old and excess network history and simplifying the network over time.
Aside from reducing historical data storage, this stage also significantly lowers the hard disk requirements for node operators and the technical debt of the Ethereum protocol.
Ethereum roadmap. Source: Vitalik Buterin
Buterin noted that introducing Ethereum improvement proposal (EIP)-6780 during the Dencun hard fork eliminated most of the “SELFDESTRUCT” code functions, which simplified the protocol by removing complexity and adding new security guarantees.
After EIP-6780, a maximum number of storage slots (roughly gas limit/5000) can be edited in a single block. Buterin hoped that in the near future, a new EIP would eliminate the SELFDESTRUCT code entirely.
The Purge will introduce history expiration via EIP-4444 to limit the amount of historical data stored. As a result, nodes will have the option to prune historical blocks that are over a year old.
The historical data will only be required when a peer has to synchronize with the head of the chain or when specifically asked for it.
Thus, when fresh blocks are confirmed, a fully synced node won’t require historical data that is more than 365 days old.
Buterin said that EIP-4444 can greatly increase Ethereum’s node decentralization.
“Potentially, if each node stores small percentages of the history by default, we could even have roughly as many copies of each specific piece of history stored across the network as we do today.”
The Ethereum co-founder also shared that Geth has recently deleted thousands of lines of code by dropping support for pre-Merge (PoW) networks.
He added that post-Dencun, an 18-day storage window for blobs will reduce the node data bandwidth to 50 gigabytes.
Buterin also discussed the need to purge precompile Ethereum contracts.
However, in recent times, the demand for the contract function has declined, and it has become a “key source of consensus bugs and a huge source of pain for new EVM implementations,” said Buterin.