In this pull request, the state iterator is implemented. It's mostly a copy-paste
from the original state snapshot package, but still has some important changes
to highlight here:
(a) The iterator for the disk layer consists of a diff iterator and a disk iterator.
Originally, the disk layer in the state snapshot was a wrapper around the disk,
and its corresponding iterator was also a wrapper around the disk iterator.
However, due to structural differences, the disk layer iterator is divided into
two parts:
- The disk iterator, which traverses the content stored on disk.
- The diff iterator, which traverses the aggregated state buffer.
Checkout `BinaryIterator` and `FastIterator` for more details.
(b) The staleness management is improved in the diffAccountIterator and
diffStorageIterator
Originally, in the `diffAccountIterator`, the layer’s staleness had to be checked
within the Next function to ensure the iterator remained usable. Additionally,
a read lock on the associated diff layer was required to first retrieve the account
blob. This read lock protection is essential to prevent concurrent map read/write.
Afterward, a staleness check was performed to ensure the retrieved data was
not outdated.
The entire logic can be simplified as follows: a loadAccount callback is provided
to retrieve account data. If the corresponding state is immutable (e.g., diff layers
in the path database), the staleness check can be skipped, and a single account
data retrieval is sufficient. However, if the corresponding state is mutable (e.g.,
the disk layer in the path database), the callback can operate as follows:
```go
func(hash common.Hash) ([]byte, error) {
dl.lock.RLock()
defer dl.lock.RUnlock()
if dl.stale {
return nil, errSnapshotStale
}
return dl.buffer.states.mustAccount(hash)
}
```
The callback solution can eliminate the complexity for managing
concurrency with the read lock for atomic operation.
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 change fixes three flaky tests `TestEth2AssembleBlock`,`TestEth2NewBlock`, `TestEth2PrepareAndGetPayload` and `TestDisable`.
---------
Co-authored-by: Gary Rong <garyrong0905@gmail.com>
This pull request introduces a database tool for inspecting the state history.
It can be used for either account history or storage slot history, within a
specific block range.
The state output format can be chosen either with
- the "rlp-encoded" values (those inserted into the merkle trie)
- the "rlp-decoded" value (the raw state value)
The latter one needs --raw flag.
As SELF-DESTRUCT opcode is disabled in the cancun fork(unless the
account is created within the same transaction, nothing to delete
in this case). The account will only be deleted in the following
cases:
- The account is created within the same transaction. In this case
the original storage was empty.
- The account is empty(zero nonce, zero balance, zero code) and
is touched within the transaction. Fortunately this kind of accounts
are not-existent on ethereum-mainnet.
All in all, after cancun, we are pretty sure there is no large contract
deletion and we don't need this mechanism for oom protection.
rjl493456442
Martin HS
Guillaume Ballet
Péter Szilágyi