Geth has two independent snapshot tiers, each with its own disable
mechanism:
1. In-memory snapshot cache: controlled by SnapshotLimit (derived from
ethconfig.SnapshotCache). Setting SnapshotCache=0 disables it.
2. On-disk snapshot generator: a background goroutine in pathdb that
iterates the entire state trie to build flat key-value snapshots.
Controlled by pathdb.Config.SnapshotNoBuild.
The partial state configuration (cmd/utils/flags.go) already set
SnapshotCache=0 to disable the in-memory cache. However, SnapshotNoBuild
was never set, so pathdb.Enable() — called after snap sync completes —
still launched the background generator goroutine.
This generator immediately hits missing storage tries for untracked
contracts (whose storage was intentionally skipped during partial sync),
logs "Trie missing, snapshotting paused", and blocks forever on its
abort channel — a permanent goroutine leak with no recovery path.
Additionally, BlockChainConfig.SnapshotNoBuild was never propagated to
pathdb.Config.SnapshotNoBuild in the triedbConfig() conversion. The
field only reached the hash-scheme snapshot module (core/blockchain.go
setupSnapshot), which is already skipped for path-scheme databases. This
plumbing gap meant pathdb.Config.SnapshotNoBuild was never set in
production code — only in tests.
Fix both issues:
- Set SnapshotNoBuild=true when partial state is enabled
- Propagate BlockChainConfig.SnapshotNoBuild into pathdb.Config
The statelessPeers map permanently blacklists peers that return empty
responses for the entire Sync() cycle. In partial state mode, the faster
account advancement (due to skipping storage/code for non-tracked
contracts) creates bursty request patterns that can trigger transient
empty responses. Combined with the permanent blacklist, this causes a
cascade where all peers get banned and sync stalls permanently.
Replace the permanent map[string]struct{} with map[string]time.Time to
track when each peer was marked. For partial state mode, peers are given
a 30-second cooldown instead of permanent banishment. After the cooldown
expires, the peer is eligible for task assignment again. Full sync mode
behavior is unchanged (permanent blacklist preserved).
Freeze the pivot header for partial state nodes to ensure stable state
sync progress:
- Suppress pivot movement in fetchHeaders() (beaconsync.go)
- Suppress pivot movement in processSnapSyncContent() (downloader.go)
- Reuse existing pivot across sync cycle restarts in syncToHead()
After initial snap sync completes, bridge the gap from pivot to HEAD:
- Import post-pivot blocks with receipts (no execution needed since
untracked contracts have empty storage tries)
- Run second state sync to download HEAD state root
- Add AdvancePartialHead to update currentBlock without re-execution
Guard the backfiller for partial state mode:
- suspend() skips Cancel() during active snap sync to prevent
constant cancel/restart cycles from beacon head updates
- resume() skips new sync cycles after partial sync completes
Refactor partial state filter from DB skip markers to direct filter
checks via shouldSyncStorage()/shouldSyncCode(), avoiding stale marker
issues across sync cycles.
Additional fixes:
- Skip WriteAccountSnapshot/WriteStorageSnapshot in partial mode
(forwardAccountTask, processStorageResponse, onHealState)
- Guard against negative ETA in reportSyncProgress when sync restarts
with persisted progress counters
- Add break after forwardAccountTask in cleanStorageTasks to prevent
nil pointer when task.res is cleared
- Add diagnostic log in assignAccountTasks when no idle peers available
Partial state nodes don't need snapshots since account data is read
directly from the trie (which is small enough for fast lookups) and
BAL-based block processing never uses snapshots.
- Set SnapshotCache to 0 when partial state is enabled (flags.go)
- Allow snap sync without snapshots for partial state mode (handler.go)
- Add nil-check for Snapshots() in snap request handlers to prevent
panics when serving HashScheme peers (snap/handler.go)
After an unclean shutdown, Disable() is called twice which is expected
behavior. The second call was logging at ERROR level, which was
misleading. Downgrade to INFO since this is a normal occurrence.
LoadPartialStateContracts() was only called from Validate() which was
never invoked, causing the contracts file to never be loaded. Call it
directly during Ethereum node initialization when partial state is
enabled.
Add chain retention for partial state mode: only the most recent N blocks
(default 1024) retain bodies and receipts. During sync, older blocks are
skipped entirely. After sync, the freezer enforces a rolling window.
Add engine API support for Block Access Lists (EIP-7928): NewPayloadV5
accepts BAL data alongside execution payloads, enabling partial state
nodes to receive per-block storage access information from the CL.
Fix beacon backfilling failure caused by dynamic chain cutoff not
clearing the cutoff hash (which remained at the genesis hash).
Add partial state awareness to eth_call/eth_estimateGas to return clear
errors when accessing untracked contract storage.
Add partial state mode support to the RPC API. In partial state mode:
- Account queries (balance, nonce, account proofs) work for ALL accounts
- Storage/code queries only work for tracked contracts
- Clear error codes help clients understand limitations
Changes:
- New error types: StorageNotTrackedError (-32001), CodeNotTrackedError (-32002)
- Backend interface: PartialStateEnabled(), IsContractTracked()
- Modified RPCs: GetStorageAt, GetCode, GetProof check tracked status
- 7 new tests verify correct behavior for tracked/untracked contracts
Implement Block Access List (BAL) processing for partial statefulness
per EIP-7928. This enables nodes to update state without re-executing
transactions by applying BAL diffs directly to the trie.
Key additions:
- ApplyBALAndComputeRoot: Core BAL processing with correct commit ordering
(storage trie → account Root → account trie)
- ProcessBlockWithBAL: Blockchain-level entry point for BAL processing
- HandlePartialReorg: Chain reorganization support using BAL history
- Comprehensive test coverage (31 tests):
* Unit tests for edge cases (storage deletion, EIP-161, buildStateSet)
* Blockchain integration tests (ProcessBlockWithBAL, HandlePartialReorg)
* Both HashScheme and PathScheme coverage
Devnet Testing (2-node setup):
- Full node: dev mode with --dev.period 2, creates blocks
- Partial node: --partial-state mode, syncs via P2P
- Test results: Block sync verified, balance queries match between nodes,
state roots consistent. Database size reduction observed for partial node.
Comprehensive integration tests using mock peers that verify partial
sync behavior end-to-end:
- TestPartialSyncIntegration: Full sync with 20 accounts, 2 tracked
- TestPartialSyncAllAccounts: Verifies complete account trie synced
- TestPartialSyncSkipMarkers: Verifies skip markers written correctly
- TestPartialSyncNoStorageForUntracked: No storage for skipped accounts
- TestPartialSyncRequestCount: Diagnostic showing request filtering
- TestPartialSyncVsFullSync: Compares full vs partial, shows 83% reduction
Level 2 validation was also performed using a two-node local devnet
(full node + partial node) to verify database size reduction and
correct RPC responses. The mock peer tests provide equivalent coverage
with faster execution and CI compatibility.
Part of partial statefulness Phase 2.
Adds partial sync mode to the snap syncer that filters which contracts
have their storage and bytecode synced based on the configured filter.
Key changes:
- Syncer accepts optional ContractFilter for partial mode
- Skip markers (SnapSkipped prefix) track intentionally skipped accounts
- processAccountResponse checks filter before requesting storage/code
- Healing phase uses NewPartialStateSync to respect skip markers
- Helper functions for skip marker persistence (mark/check/delete)
When partial sync is active, only tracked contracts have their storage
synced, reducing sync size from ~1TB+ to ~30-40GB while maintaining
a complete account trie for balance queries.
Part of partial statefulness Phase 2.
Passes the partial statefulness filter from Ethereum backend through
the handler config and into the downloader. The filter is then passed
to the snap syncer to enable selective storage/code syncing.
Updates downloader tests to accommodate the new filter parameter.
Part of partial statefulness Phase 2.
Extends ContractFilter interface with hash-based methods (ShouldSyncStorageByHash,
ShouldSyncCodeByHash) for efficient filtering during snap sync when only account
hashes are available.
Adds NewPartialStateSync() function that accepts filter callbacks to control which
accounts have their storage/code synced during healing. This prevents the healing
phase from re-syncing storage for accounts that were intentionally skipped during
initial sync.
Part of partial statefulness Phase 2.
Implements EIP-7928 BAL-based partial statefulness infrastructure:
- Add PartialStateConfig to eth/ethconfig with CLI flags
- Add ContractFilter interface in core/state/partial/
- Add BAL history database accessors in core/rawdb/
- Add PartialState and BALHistory managers
This enables nodes to track only configured contracts' storage
while maintaining full account trie integrity.
Wire up slotnum for `testing_buildBlockV1` for `bal-devnet-3` branch
We are experimenting testing block building through hive via EELS (PR
[here](https://github.com/ethereum/execution-specs/pull/2679)). This is
the only change needed to test against `bal-devnet-3` - missing slotnum.
The BAL reader tracker captures access list reads at the reader level.
When statedb has an account cached the BAL tracker is not informed of
the access. This is ok during the lifetime of a transaction because you
only need to record the access the first time. It is also ok during the
lifetime of a block because BAL reads are block-level (same as statedb
caches).
Where I think the issue can rise is in the miner. Namely when building a
block, if the miner picks up a tx which fails, it drops it and picks up
another tx to include. There might be some edge case here where the
failed tx which is not included poisons the cache and a future block
which is included omits an account because it wasn't aware of the
access.
To check whether a transaction can be applied, we validate that
`blockGasLimit > txGasLimit + (cumulativeRegularGasUsed +
cumulativeStateGasUsed)`. However, the check should only be applied to
the bottleneck resource, i.e. `blockGasLimit >
max(txRegularGasUsed+cumulativeRegularGasUsed, txStateGasUsed+
cumulativeStateGasUsed)`.
The changes here break multiple tests. I am trying to determine why.
---------
Co-authored-by: qu0b <stefan@starflinger.eu>
## Summary
- The BAL refactoring in 5808d212b removed the line `env.header.GasUsed
= env.gasPool.Used()` from `applyTransaction()`, causing all
geth-proposed blocks to have `GasUsed=0` in the header
- Every other client rejects these blocks during validation, so geth can
never successfully propose on the network
- Restores the single line that was present in upstream master
## Test plan
- [x] Verified line exists in upstream/master at miner/worker.go:409
- [x] Confirmed all 34 geth-proposed blocks on a 4-client devnet had
`GasUsed=0` via `debug_getBadBlocks` on besu
- [ ] Build local image and verify geth proposals are accepted in a
multi-client Kurtosis network
* add method on StateReaderTracker to clear the accumulated reads
* don't factor the BAL size into the payload size during construction in the miner
* simplify miner code for constructing payloads-with-BALs via the use of aformentioned StateReaderTracker clear method
* clean up the configuration of the BAL execution mode based on the preset flag specified
Adds support for returning `blockAccessListHash` in the RPC block header
response.
This change includes `blockAccessListHash` in `RPCMarshalHeader` when
`head.BlockAccessListHash` is not nil, aligning the RPC output with the
Header struct which already contains this field.
CopyHeader copies all pointer-typed header fields (WithdrawalsHash,
RequestsHash, SlotNumber, etc.) but was missing the deep copy for
BlockAccessListHash added by EIP-7928. This caused the BAL hash
to be silently shared between the original and the copy, leading
to potential data races and incorrect nil-checks on copied headers.
This is a breaking change in the opcode (structLog) tracer. Several fields
will have a slight formatting difference to conform to the newly established
spec at: https://github.com/ethereum/execution-apis/pull/762. The differences
include:
- `memory`: words will have the 0x prefix. Also last word of memory will be padded to 32-bytes.
- `storage`: keys and values will have the 0x prefix.
---------
Co-authored-by: Sina M <1591639+s1na@users.noreply.github.com>
