This pull request delivers the new version of the state history, where
the raw storage key is used instead of the hash.
Before the cancun fork, it's supported by protocol to destruct a
specific account and therefore, all the storage slot owned by it should
be wiped in the same transition.
Technically, storage wiping should be performed through storage
iteration, and only the storage key hash will be available for traversal
if the state snapshot is not available. Therefore, the storage key hash
is chosen as the identifier in the old version state history.
Fortunately, account self-destruction has been deprecated by the
protocol since the Cancun fork, and there are no empty accounts eligible
for deletion under EIP-158. Therefore, we can conclude that no storage
wiping should occur after the Cancun fork. In this case, it makes no
sense to keep using hash.
Besides, another big reason for making this change is the current format
state history is unusable if verkle is activated. Verkle tree has a
different key derivation scheme (merkle uses keccak256), the preimage of
key hash must be provided in order to make verkle rollback functional.
This pull request is a prerequisite for landing verkle.
Additionally, the raw storage key is more human-friendly for those who
want to manually check the history, even though Solidity already
performs some hashing to derive the storage location.
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This pull request doesn't bump the database version, as I believe the
database should still be compatible if users degrade from the new geth
version to old one, the only side effect is the persistent new version
state history will be unusable.
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Co-authored-by: Zsolt Felfoldi <zsfelfoldi@gmail.com>
This pull request ports some changes from the main state snapshot
integration one, specifically introducing the flat state tracking in
pathdb.
Note, the tracked flat state changes are only held in memory and won't
be persisted in the disk. Meanwhile, the correspoding state retrieval in
persistent state is also not supported yet. The states management in
disk is more complicated and will be implemented in a separate pull
request.
Part 1: https://github.com/ethereum/go-ethereum/pull/30752
This pull request removes the destruct flag from the state snapshot to
simplify the code.
Previously, this flag indicated that an account was removed during a
state transition, making all associated storage slots inaccessible.
Because storage deletion can involve a large number of slots, the actual
deletion is deferred until the end of the process, where it is handled
in batches.
With the deprecation of self-destruct in the Cancun fork, storage
deletions are no longer expected. Historically, the largest storage
deletion event in Ethereum was around 15 megabytes—manageable in memory.
In this pull request, the single destruct flag is replaced by a set of
deletion markers for individual storage slots. Each deleted storage slot
will now appear in the Storage set with a nil value.
This change will simplify a lot logics, such as storage accessing,
storage flushing, storage iteration and so on.
rjl493456442