core, accounts, eth, trie: handle genesis state missing #28171

rjl493456442 · 2023-09-21T07:45:16Z

This pull request addresses scenarios where the associated head state is missing.

In the original design, the chain head would never be stateless because the genesis state was always considered present, and we could always rewind the chain back to the genesis block. However, in path mode, the genesis state may have already been overwritten by the state syncer, making recovery impossible.

As a result, it is important to ensure that even when the chain is in a stateless condition, everything continues to function smoothly until the state synchronization process is fully completed.

The lazy initialization is introduces to txpool if the chain is stateless, it's looks a bit ugly, but no idea how to make it elegant.

A few scenarios need to be tested:

eth/backend.go

rjl493456442 · 2023-09-24T01:37:34Z

eth/handler.go

-		if err == nil {
-			h.enableSyncedFeatures() // Mark initial sync done on any fetcher import
-		}
-		return n, err


The node will only be marked as initialized after the initial sync cycle. There are some behavioral changes in legacy un-merged chain, but it's fine, just do a tiny full-sync instead of a single block fetch.

What happens with empty networks that are just starting up? They can't do any type of sync because there's nothing yet to sync

Ah this is specifically the fetcher path. Still in that case, what happens if my node never does a sync cycle because it's always in sync and connected?

enableSyncedFeatures will be called if (1) mining is enabled or (2) we successfully do a forkchoiceUpdate. Basically block producer will be marked as synced to generate blocks and it will trigger other nodes to sync.

rjl493456442 · 2023-09-25T09:00:59Z

Btw, for the reviewers, https://github.com/ethereum/go-ethereum/blob/master/eth/handler.go#L248 here snapSync is used to determine if new blocks should be accepted by block fetcher or not. It looks a bit confusing, can I change it to use synced flag, which means reject any block insertion while node is not fully synced?

trie/triedb/pathdb/errors.go

trie/triedb/pathdb/database.go

core/rawdb/schema.go

trie/triedb/pathdb/database.go

eth/handler.go

core/txpool/txpool.go

trie/database.go

karalabe

LGTM

* core, accounts, eth, trie: handle genesis state missing * core, eth, trie: polish * core: manage txpool subscription in mainpool * eth/backend: fix test * cmd, eth: fix test * core/rawdb, trie/triedb/pathdb: address comments * eth, trie: address comments * eth: inline the function * eth: use synced flag * core/txpool: revert changes in txpool * core, eth, trie: rename functions

…reum#28171)" This reverts commit bcc2e34.

core, accounts, eth, trie: handle genesis state missing (ethereum#28171) Conflicts: core/blockchain.go We made many changes in setHeadBeyondRoot. upstream removed assumption that genesis state is always in the db. Accepted both changes

rjl493456442 requested review from karalabe, holiman, gballet and MariusVanDerWijden as code owners September 21, 2023 07:45

rjl493456442 commented Sep 24, 2023

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rjl493456442 commented Sep 24, 2023

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rjl493456442 force-pushed the no-state branch 2 times, most recently from 1af3bf2 to 4e619ba Compare September 24, 2023 14:04