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.
---
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.
---------
Co-authored-by: Zsolt Felfoldi <zsfelfoldi@gmail.com>
This pull request refactors the genesis setup function, the major
changes are highlighted here:
**(a) Triedb is opened in verkle mode if `EnableVerkleAtGenesis` is
configured in chainConfig or the database has been initialized previously with
`EnableVerkleAtGenesis` configured**.
A new config field `EnableVerkleAtGenesis` has been added in the
chainConfig. This field must be configured with True if Geth wants to initialize
the genesis in Verkle mode.
In the verkle devnet-7, the verkle transition is activated at genesis.
Therefore, the verkle rules should be used since the genesis. In production
networks (mainnet and public testnets), verkle activation always occurs after
the genesis block. Therefore, this flag is only made for devnet and should be
deprecated later. Besides, verkle transition at non-genesis block hasn't been
implemented yet, it should be done in the following PRs.
**(b) The genesis initialization condition has been simplified**
There is a special mode supported by the Geth is that: Geth can be
initialized with an existing chain segment, which can fasten the node sync
process by retaining the chain freezer folder.
Originally, if the triedb is regarded as uninitialized and the genesis block can
be found in the chain freezer, the genesis block along with genesis state will be
committed. This condition has been simplified to checking the presence of chain
config in key-value store. The existence of chain config can represent the genesis
has been committed.
As the node hash scheme in verkle and merkle are totally different, the
original default node hasher in pathdb is no longer suitable. Therefore,
this pull request configures different node hasher respectively.
This change fixes is a rare bug in test generator: If the run is very unlucky it
can use `modifyAccountOp` / `deleteAccountOp` without creating any
account, leading to have a trie root same as the parent.
This change makes the first operation always be a creation.
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 PR modifies how the metrics library handles `Enabled`: previously,
the package `init` decided whether to serve real metrics or just
dummy-types.
This has several drawbacks:
- During pkg init, we need to determine whether metrics are enabled or
not. So we first hacked in a check if certain geth-specific
commandline-flags were enabled. Then we added a similar check for
geth-env-vars. Then we almost added a very elaborate check for
toml-config-file, plus toml parsing.
- Using "real" types and dummy types interchangeably means that
everything is hidden behind interfaces. This has a performance penalty,
and also it just adds a lot of code.
This PR removes the interface stuff, uses concrete types, and allows for
the setting of Enabled to happen later. It is still assumed that
`metrics.Enable()` is invoked early on.
The somewhat 'heavy' operations, such as ticking meters and exp-decay,
now checks the enable-flag to prevent resource leak.
The change may be large, but it's mostly pretty trivial, and from the
last time I gutted the metrics, I ensured that we have fairly good test
coverage.
---------
Co-authored-by: Felix Lange <fjl@twurst.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.
This PR fixes some issues with benchmarks
- [x] Removes log output from a log-test
- [x] Avoids a `nil`-defer in `triedb/pathdb`
- [x] Fixes some crashes re tracers
- [x] Refactors a very resource-expensive benchmark for blobpol.
**NOTE**: this rewrite touches live production code (a little bit), as
it makes the validator-function used by the blobpool configurable.
- [x] Switch some benches over to use pebble over leveldb
- [x] reduce mem overhead in the setup-phase of some tests
- [x] Marks some tests with a long setup-phase to be skipped if `-short`
is specified (where long is on the order of tens of seconds). Ideally,
in my opinion, one should be able to run with `-benchtime 10ms -short`
and sanity-check all tests very quickly.
- [x] Drops some metrics-bechmark which times the speed of `copy`.
---------
Co-authored-by: Sina Mahmoodi <itz.s1na@gmail.com>
This pull request removes the `fsync` of index files in freezer.ModifyAncients function for
performance gain.
Originally, fsync is added after each freezer write operation to ensure
the written data is truly transferred into disk. Unfortunately, it turns
out `fsync` can be relatively slow, especially on
macOS (see https://github.com/ethereum/go-ethereum/issues/28754 for more
information).
In this pull request, fsync for index file is removed as it turns out
index file can be recovered even after a unclean shutdown. But fsync for data file is still kept, as
we have no meaningful way to validate the data correctness after unclean shutdown.
---
**But why do we need the `fsync` in the first place?**
As it's necessary for freezer to survive/recover after the machine crash
(e.g. power failure).
In linux, whenever the file write is performed, the file metadata update
and data update are
not necessarily performed at the same time. Typically, the metadata will
be flushed/journalled
ahead of the file data. Therefore, we make the pessimistic assumption
that the file is first
extended with invalid "garbage" data (normally zero bytes) and that
afterwards the correct
data replaces the garbage.
We have observed that the index file of the freezer often contain
garbage entry with zero value
(filenumber = 0, offset = 0) after a machine power failure. It proves
that the index file is extended
without the data being flushed. And this corruption can destroy the
whole freezer data eventually.
Performing fsync after each write operation can reduce the time window
for data to be transferred
to the disk and ensure the correctness of the data in the disk to the
greatest extent.
---
**How can we maintain this guarantee without relying on fsync?**
Because the items in the index file are strictly in order, we can
leverage this characteristic to
detect the corruption and truncate them when freezer is opened.
Specifically these validation
rules are performed for each index file:
For two consecutive index items:
- If their file numbers are the same, then the offset of the latter one
MUST not be less than that of the former.
- If the file number of the latter one is equal to that of the former
plus one, then the offset of the latter one MUST not be 0.
- If their file numbers are not equal, and the latter's file number is
not equal to the former plus 1, the latter one is valid
And also, for the first non-head item, it must refer to the earliest
data file, or the next file if the
earliest file is not sufficient to place the first item(very special
case, only theoretical possible
in tests)
With these validation rules, we can detect the invalid item in index
file with greatest possibility.
---
But unfortunately, these scenarios are not covered and could still lead
to a freezer corruption if it occurs:
**All items in index file are in zero value**
It's impossible to distinguish if they are truly zero (e.g. all the data
entries maintained in freezer
are zero size) or just the garbage left by OS. In this case, these index
items will be kept by truncating
the entire data file, namely the freezer is corrupted.
However, we can consider that the probability of this situation
occurring is quite low, and even
if it occurs, the freezer can be considered to be close to an empty
state. Rerun the state sync
should be acceptable.
**Index file is integral while relative data file is corrupted**
It might be possible the data file is corrupted whose file size is
extended correctly with garbage
filled (e.g. zero bytes). In this case, it's impossible to detect the
corruption by index validation.
We can either choose to `fsync` the data file, or blindly believe that
if index file is integral then
the data file could be integral with very high chance. In this pull
request, the first option is taken.
This pull request introduces a state.Reader interface for state
accessing.
The interface could be implemented in various ways. It can be pure trie
only reader, or the combination of trie and state snapshot. What's more,
this interface allows us to have more flexibility in the future, e.g.
the
archive reader (for accessing archive state).
Additionally, this pull request removes the following metrics
- `chain/snapshot/account/reads`
- `chain/snapshot/storage/reads`
This pull request adds a few more performance metrics, specifically:
- The average time cost of an account read
- The average time cost of a storage read
- The rate of account reads
- The rate of storage reads
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.