Block History Expiry

[jflo]

Description

As a node operator, I would like to recover the 500GB of storage used by historical blocks, prior to the merge, if I do not intend to run an archive node. If I do intend to run an archive node, I want to retain those blocks, and also have access to them if I want to start up a new archive node from scratch.

User Scenarios

Most Users:

• start preferring eth70 over eth68 connections.
  • users may drop pre-merge blocks, recovering space.
  • eth68 peers will still connect, but may disconnect us when we do not have historical blocks they request.
  • new users will be doing CHECKPOINT_SYNC from the merge instead of beacon chain genesis.

Current Archivists:

• no problem. start serving eth/70
• keep honoring eth/68.
• start serving etha with a full bitmask

New Archivists:

I need to backfill blocks, but everyone is on eth/70! I have 3 options.

1. seek out peers supporting eth/68
2. load in all blocks from genesis to the merge via an ERA loader.
3. connect to the portal network

Once populated, you have the same requirements as Current Archivists do.

new archetype: Partial Archive Node.

• start serving eth/70
• honor eth/68
• choose how much pre-merge history you want to serve.
• source that from either
  • eth/68 peers
  • portal network
• start serving etha with the corresponding bitmask