Jacek Sieka 8d465a7d8c
vmon: Missed block metric (#5913)
Validator monitoring gained 2 new metrics for tracking when blocks are
included or not on the head chain.

Similar to attestations, if the block is produced in epoch N, reporting
will use the state when switching to epoch N+2 to do the reporting (so
as to reasonably stabilise the block inclusion in the face of reorgs).
2024-02-20 06:40:18 +02:00

2859 lines
108 KiB
Nim

# beacon_chain
# Copyright (c) 2018-2024 Status Research & Development GmbH
# Licensed and distributed under either of
# * MIT license (license terms in the root directory or at https://opensource.org/licenses/MIT).
# * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0).
# at your option. This file may not be copied, modified, or distributed except according to those terms.
{.push raises: [].}
import
std/[algorithm, sequtils, tables, sets],
stew/[arrayops, assign2, byteutils],
metrics, results, snappy, chronicles,
../spec/[beaconstate, eth2_merkleization, eth2_ssz_serialization, helpers,
state_transition, validator],
../spec/forks,
../spec/datatypes/[phase0, altair, bellatrix, capella],
".."/[beacon_chain_db, beacon_clock, era_db],
"."/[block_pools_types, block_quarantine]
from ../spec/datatypes/deneb import shortLog
export
eth2_merkleization, eth2_ssz_serialization,
block_pools_types, results, beacon_chain_db
logScope: topics = "chaindag"
# https://github.com/ethereum/beacon-metrics/blob/master/metrics.md#interop-metrics
declareGauge beacon_head_root, "Root of the head block of the beacon chain"
declareGauge beacon_head_slot, "Slot of the head block of the beacon chain"
# https://github.com/ethereum/beacon-metrics/blob/master/metrics.md#interop-metrics
declareGauge beacon_finalized_epoch, "Current finalized epoch" # On epoch transition
declareGauge beacon_finalized_root, "Current finalized root" # On epoch transition
declareGauge beacon_current_justified_epoch, "Current justified epoch" # On epoch transition
declareGauge beacon_current_justified_root, "Current justified root" # On epoch transition
declareGauge beacon_previous_justified_epoch, "Current previously justified epoch" # On epoch transition
declareGauge beacon_previous_justified_root, "Current previously justified root" # On epoch transition
declareGauge beacon_reorgs_total_total, "Total occurrences of reorganizations of the chain" # On fork choice; backwards-compat name (used to be a counter)
declareGauge beacon_reorgs_total, "Total occurrences of reorganizations of the chain" # Interop copy
declareCounter beacon_state_data_cache_hits, "EpochRef hits"
declareCounter beacon_state_data_cache_misses, "EpochRef misses"
declareCounter beacon_state_rewinds, "State database rewinds"
declareGauge beacon_active_validators, "Number of validators in the active validator set"
declareGauge beacon_current_active_validators, "Number of validators in the active validator set" # Interop copy
declareGauge beacon_pending_deposits, "Number of pending deposits (state.eth1_data.deposit_count - state.eth1_deposit_index)" # On block
declareGauge beacon_processed_deposits_total, "Number of total deposits included on chain" # On block
declareCounter total_state_replay_seconds, "Total time spent replaying states"
const
EPOCHS_PER_STATE_SNAPSHOT* = 32
## When finality happens, we prune historical states from the database except
## for a snapshot every 32 epochs from which replays can happen - there's a
## balance here between making long replays and saving on disk space
MAX_SLOTS_PER_PRUNE* = SLOTS_PER_EPOCH
## We prune the database incrementally so as not to introduce long
## processing breaks - this number is the maximum number of blocks we allow
## to be pruned every time the prune call is made (once per slot typically)
## unless head is moving faster (ie during sync)
proc putBlock*(
dag: ChainDAGRef, signedBlock: ForkyTrustedSignedBeaconBlock) =
dag.db.putBlock(signedBlock)
proc updateState*(
dag: ChainDAGRef, state: var ForkedHashedBeaconState, bsi: BlockSlotId,
save: bool, cache: var StateCache): bool {.gcsafe.}
template withUpdatedState*(
dag: ChainDAGRef, stateParam: var ForkedHashedBeaconState,
bsiParam: BlockSlotId, okBody: untyped, failureBody: untyped): untyped =
## Helper template that updates stateData to a particular BlockSlot - usage of
## stateData is unsafe outside of block, or across `await` boundaries
block:
let bsi {.inject.} = bsiParam
var cache {.inject.} = StateCache()
if updateState(dag, stateParam, bsi, false, cache):
template bid(): BlockId {.inject, used.} = bsi.bid
template updatedState(): ForkedHashedBeaconState {.inject, used.} = stateParam
okBody
else:
failureBody
func get_effective_balances(
validators: openArray[Validator], epoch: Epoch): seq[Gwei] =
## Get the balances from a state as counted for fork choice
result.newSeq(validators.len) # zero-init
for i in 0 ..< result.len:
# All non-active validators have a 0 balance
let validator = unsafeAddr validators[i]
if validator[].is_active_validator(epoch) and not validator[].slashed:
result[i] = validator[].effective_balance
proc updateValidatorKeys*(dag: ChainDAGRef, validators: openArray[Validator]) =
# Update validator key cache - must be called every time a valid block is
# applied to the state - this is important to ensure that when we sync blocks
# without storing a state (non-epoch blocks essentially), the deposits from
# those blocks are persisted to the in-database cache of immutable validator
# data (but no earlier than that the whole block as been validated)
dag.db.updateImmutableValidators(validators)
proc updateFinalizedBlocks*(db: BeaconChainDB, newFinalized: openArray[BlockId]) =
if db.db.readOnly: return # TODO abstraction leak - where to put this?
db.withManyWrites:
for bid in newFinalized:
db.finalizedBlocks.insert(bid.slot, bid.root)
proc updateFrontfillBlocks*(dag: ChainDAGRef) =
# When backfilling is done and manages to reach the frontfill point, we can
# write the frontfill index knowing that the block information in the
# era files match the chain
if dag.db.db.readOnly: return # TODO abstraction leak - where to put this?
if dag.frontfillBlocks.len == 0 or dag.backfill.slot > GENESIS_SLOT:
return
info "Writing frontfill index", slots = dag.frontfillBlocks.len
dag.db.withManyWrites:
let low = dag.db.finalizedBlocks.low.expect(
"wrote at least tailRef during init")
let blocks = min(low.int, dag.frontfillBlocks.len - 1)
var parent: Eth2Digest
for i in 0..blocks:
let root = dag.frontfillBlocks[i]
if not isZero(root):
dag.db.finalizedBlocks.insert(Slot(i), root)
dag.db.putBeaconBlockSummary(
root, BeaconBlockSummary(slot: Slot(i), parent_root: parent))
parent = root
reset(dag.frontfillBlocks)
func validatorKey*(
dag: ChainDAGRef, index: ValidatorIndex or uint64): Opt[CookedPubKey] =
## Returns the validator pubkey for the index, assuming it's been observed
## at any point in time - this function may return pubkeys for indicies that
## are not (yet) part of the head state (if the key has been observed on a
## non-head branch)!
dag.db.immutableValidators.load(index)
template is_merge_transition_complete*(
stateParam: ForkedHashedBeaconState): bool =
withState(stateParam):
when consensusFork >= ConsensusFork.Bellatrix:
is_merge_transition_complete(forkyState.data)
else:
false
func effective_balances*(epochRef: EpochRef): seq[Gwei] =
try:
SSZ.decode(snappy.decode(epochRef.effective_balances_bytes, uint32.high),
List[Gwei, Limit VALIDATOR_REGISTRY_LIMIT]).toSeq()
except CatchableError as exc:
raiseAssert exc.msg
func getBlockRef*(dag: ChainDAGRef, root: Eth2Digest): Opt[BlockRef] =
## Retrieve a resolved block reference, if available - this function does
## not return historical finalized blocks, see `getBlockIdAtSlot` for a
## function that covers the entire known history
let key = KeyedBlockRef.asLookupKey(root)
# HashSet lacks the api to do check-and-get in one lookup - `[]` will return
# the copy of the instance in the set which has more fields than `root` set!
if key in dag.forkBlocks:
try: ok(dag.forkBlocks[key].blockRef())
except KeyError: raiseAssert "contains"
else:
err()
func getBlockIdAtSlot*(
state: ForkyHashedBeaconState, slot: Slot): Opt[BlockSlotId] =
## Use given state to attempt to find a historical `BlockSlotId`.
if slot > state.data.slot:
return Opt.none(BlockSlotId) # State does not know about requested slot
if state.data.slot > slot + SLOTS_PER_HISTORICAL_ROOT:
return Opt.none(BlockSlotId) # Cache has expired
var idx = slot mod SLOTS_PER_HISTORICAL_ROOT
let root =
if slot == state.data.slot:
state.latest_block_root
else:
state.data.block_roots[idx]
var bid = BlockId(slot: slot, root: root)
let availableSlots =
min(slot.uint64, slot + SLOTS_PER_HISTORICAL_ROOT - state.data.slot)
for i in 0 ..< availableSlots:
if idx == 0:
idx = SLOTS_PER_HISTORICAL_ROOT
dec idx
if state.data.block_roots[idx] != root:
return Opt.some BlockSlotId.init(bid, slot)
dec bid.slot
if bid.slot == GENESIS_SLOT:
return Opt.some BlockSlotId.init(bid, slot)
Opt.none(BlockSlotId) # Unknown if there are more empty slots before
func getBlockIdAtSlot*(dag: ChainDAGRef, slot: Slot): Opt[BlockSlotId] =
## Retrieve the canonical block at the given slot, or the last block that
## comes before - similar to atSlot, but without the linear scan - may hit
## the database to look up early indices.
if slot > dag.finalizedHead.slot:
return dag.head.atSlot(slot).toBlockSlotId() # iterate to the given slot
if dag.finalizedHead.blck == nil:
# Not initialized yet (in init)
return Opt.none(BlockSlotId)
if slot >= dag.finalizedHead.blck.slot:
# finalized head is still in memory
return dag.finalizedHead.blck.atSlot(slot).toBlockSlotId()
# Load from memory, if the block ID is sufficiently recent.
# For checkpoint sync, this is the only available of historical block IDs
# until sufficient blocks have been backfilled.
template tryWithState(state: ForkedHashedBeaconState) =
block:
withState(state):
# State must be a descendent of the finalized chain to be viable
let finBsi = forkyState.getBlockIdAtSlot(dag.finalizedHead.slot)
if finBsi.isSome and # DAG finalized bid slot wrong if CP not @ epoch
finBsi.unsafeGet.bid.root == dag.finalizedHead.blck.bid.root:
let bsi = forkyState.getBlockIdAtSlot(slot)
if bsi.isSome:
return bsi
tryWithState dag.headState
tryWithState dag.epochRefState
tryWithState dag.clearanceState
# Fallback to database, this only works for backfilled blocks
let finlow = dag.db.finalizedBlocks.low.expect("at least tailRef written")
if slot >= finlow:
var pos = slot
while true:
let root = dag.db.finalizedBlocks.get(pos)
if root.isSome():
return ok BlockSlotId.init(
BlockId(root: root.get(), slot: pos), slot)
doAssert pos > finlow, "We should have returned the finlow"
pos = pos - 1
if slot == GENESIS_SLOT and dag.genesis.isSome():
return ok dag.genesis.get().atSlot()
err() # not backfilled yet
proc containsBlock(
cfg: RuntimeConfig, db: BeaconChainDB, slot: Slot, root: Eth2Digest): bool =
db.containsBlock(root, cfg.consensusForkAtEpoch(slot.epoch))
proc containsBlock*(dag: ChainDAGRef, bid: BlockId): bool =
dag.cfg.containsBlock(dag.db, bid.slot, bid.root)
proc getForkedBlock*(db: BeaconChainDB, root: Eth2Digest):
Opt[ForkedTrustedSignedBeaconBlock] =
# When we only have a digest, we don't know which fork it's from so we try
# them one by one - this should be used sparingly
static: doAssert high(ConsensusFork) == ConsensusFork.Deneb
if (let blck = db.getBlock(root, deneb.TrustedSignedBeaconBlock);
blck.isSome()):
ok(ForkedTrustedSignedBeaconBlock.init(blck.get()))
elif (let blck = db.getBlock(root, capella.TrustedSignedBeaconBlock);
blck.isSome()):
ok(ForkedTrustedSignedBeaconBlock.init(blck.get()))
elif (let blck = db.getBlock(root, bellatrix.TrustedSignedBeaconBlock);
blck.isSome()):
ok(ForkedTrustedSignedBeaconBlock.init(blck.get()))
elif (let blck = db.getBlock(root, altair.TrustedSignedBeaconBlock);
blck.isSome()):
ok(ForkedTrustedSignedBeaconBlock.init(blck.get()))
elif (let blck = db.getBlock(root, phase0.TrustedSignedBeaconBlock);
blck.isSome()):
ok(ForkedTrustedSignedBeaconBlock.init(blck.get()))
else:
err()
proc getBlock*(
dag: ChainDAGRef, bid: BlockId,
T: type ForkyTrustedSignedBeaconBlock): Opt[T] =
dag.db.getBlock(bid.root, T) or
getBlock(
dag.era, getStateField(dag.headState, historical_roots).asSeq,
dag.headState.historical_summaries().asSeq,
bid.slot, Opt[Eth2Digest].ok(bid.root), T)
proc getBlockSSZ*(dag: ChainDAGRef, bid: BlockId, bytes: var seq[byte]): bool =
# Load the SSZ-encoded data of a block into `bytes`, overwriting the existing
# content
let fork = dag.cfg.consensusForkAtEpoch(bid.slot.epoch)
dag.db.getBlockSSZ(bid.root, bytes, fork) or
(bid.slot <= dag.finalizedHead.slot and
getBlockSSZ(
dag.era, getStateField(dag.headState, historical_roots).asSeq,
dag.headState.historical_summaries().asSeq,
bid.slot, bytes).isOk() and bytes.len > 0)
proc getBlockSZ*(dag: ChainDAGRef, bid: BlockId, bytes: var seq[byte]): bool =
# Load the snappy-frame-compressed ("SZ") SSZ-encoded data of a block into
# `bytes`, overwriting the existing content
# careful: there are two snappy encodings in use, with and without framing!
# Returns true if the block is found, false if not
let fork = dag.cfg.consensusForkAtEpoch(bid.slot.epoch)
dag.db.getBlockSZ(bid.root, bytes, fork) or
(bid.slot <= dag.finalizedHead.slot and
getBlockSZ(
dag.era, getStateField(dag.headState, historical_roots).asSeq,
dag.headState.historical_summaries().asSeq,
bid.slot, bytes).isOk and bytes.len > 0)
proc getForkedBlock*(
dag: ChainDAGRef, bid: BlockId): Opt[ForkedTrustedSignedBeaconBlock] =
let fork = dag.cfg.consensusForkAtEpoch(bid.slot.epoch)
result.ok(ForkedTrustedSignedBeaconBlock(kind: fork))
withBlck(result.get()):
type T = type(forkyBlck)
forkyBlck = getBlock(dag, bid, T).valueOr:
getBlock(
dag.era, getStateField(dag.headState, historical_roots).asSeq,
dag.headState.historical_summaries().asSeq,
bid.slot, Opt[Eth2Digest].ok(bid.root), T).valueOr:
result.err()
return
proc getBlockId*(db: BeaconChainDB, root: Eth2Digest): Opt[BlockId] =
block: # We might have a summary in the database
let summary = db.getBeaconBlockSummary(root)
if summary.isOk():
return ok(BlockId(root: root, slot: summary.get().slot))
block:
# We might have a block without having written a summary - this can happen
# if there was a crash between writing the block and writing the summary,
# specially in databases written by older nimbus versions
let forked = db.getForkedBlock(root)
if forked.isSome():
# Shouldn't happen too often but..
let
blck = forked.get()
summary = withBlck(blck): forkyBlck.message.toBeaconBlockSummary()
debug "Writing summary", blck = shortLog(blck)
db.putBeaconBlockSummary(root, summary)
return ok(BlockId(root: root, slot: summary.slot))
err()
proc getBlockId*(dag: ChainDAGRef, root: Eth2Digest): Opt[BlockId] =
## Look up block id by root in history - useful for turning a root into a
## slot - may hit the database, may return blocks that have since become
## unviable - use `getBlockIdAtSlot` to check that the block is still viable
## if used in a sensitive context
block: # If we have a BlockRef, this is the fastest way to get a block id
let blck = dag.getBlockRef(root)
if blck.isOk():
return ok(blck.get().bid)
dag.db.getBlockId(root)
proc getForkedBlock*(
dag: ChainDAGRef, root: Eth2Digest): Opt[ForkedTrustedSignedBeaconBlock] =
let bid = dag.getBlockId(root)
if bid.isSome():
dag.getForkedBlock(bid.get())
else:
# In case we didn't have a summary - should be rare, but ..
dag.db.getForkedBlock(root)
func isCanonical*(dag: ChainDAGRef, bid: BlockId): bool =
## Returns `true` if the given `bid` is part of the history selected by
## `dag.head`.
let current = dag.getBlockIdAtSlot(bid.slot).valueOr:
return false # We don't know, so ..
return current.bid == bid
func isFinalized*(dag: ChainDAGRef, bid: BlockId): bool =
## Returns `true` if the given `bid` is part of the finalized history
## selected by `dag.finalizedHead`.
dag.isCanonical(bid) and (bid.slot <= dag.finalizedHead.slot)
func parent*(dag: ChainDAGRef, bid: BlockId): Opt[BlockId] =
if bid.slot == 0:
return err()
if bid.slot > dag.finalizedHead.slot:
# Make sure we follow the correct history as there may be forks
let blck = ? dag.getBlockRef(bid.root)
doAssert not isNil(blck.parent), "should reach finalized head"
return ok blck.parent.bid
let bids = ? dag.getBlockIdAtSlot(bid.slot - 1)
ok(bids.bid)
func parentOrSlot*(dag: ChainDAGRef, bsi: BlockSlotId): Opt[BlockSlotId] =
if bsi.slot == 0:
return err()
if bsi.isProposed:
let parent = ? dag.parent(bsi.bid)
ok BlockSlotId.init(parent, bsi.slot)
else:
ok BlockSlotId.init(bsi.bid, bsi.slot - 1)
func atSlot*(dag: ChainDAGRef, bid: BlockId, slot: Slot): Opt[BlockSlotId] =
if bid.slot > dag.finalizedHead.slot:
let blck = ? dag.getBlockRef(bid.root)
if slot > dag.finalizedHead.slot:
return blck.atSlot(slot).toBlockSlotId()
else:
# Check if the given `bid` is still part of history - it might hail from an
# orphaned fork
let existing = ? dag.getBlockIdAtSlot(bid.slot)
if existing.bid != bid:
return err() # Not part of known / relevant history
if existing.slot == slot: # and bid.slot == slot
return ok existing
if bid.slot <= slot:
ok BlockSlotId.init(bid, slot)
else:
dag.getBlockIdAtSlot(slot)
func nextTimestamp[I, T](cache: var LRUCache[I, T]): uint32 =
if cache.timestamp == uint32.high:
for i in 0 ..< I:
template e: untyped = cache.entries[i]
if e.lastUsed != 0:
e.lastUsed = 1
cache.timestamp = 1
inc cache.timestamp
cache.timestamp
template peekIt[I, T](cache: var LRUCache[I, T], predicate: untyped): Opt[T] =
block:
var res: Opt[T]
for i in 0 ..< I:
template e: untyped = cache.entries[i]
template it: untyped {.inject, used.} = e.value
if e.lastUsed != 0 and predicate:
res.ok it
break
res
template findIt[I, T](cache: var LRUCache[I, T], predicate: untyped): Opt[T] =
block:
var res: Opt[T]
for i in 0 ..< I:
template e: untyped = cache.entries[i]
template it: untyped {.inject, used.} = e.value
if e.lastUsed != 0 and predicate:
e.lastUsed = cache.nextTimestamp
res.ok it
break
res
template delIt[I, T](cache: var LRUCache[I, T], predicate: untyped) =
block:
for i in 0 ..< I:
template e: untyped = cache.entries[i]
template it: untyped {.inject, used.} = e.value
if e.lastUsed != 0 and predicate:
e.reset()
func put[I, T](cache: var LRUCache[I, T], value: T) =
var lru = 0
block:
var min = uint32.high
for i in 0 ..< I:
template e: untyped = cache.entries[i]
if e.lastUsed < min:
min = e.lastUsed
lru = i
if min == 0:
break
template e: untyped = cache.entries[lru]
e.value = value
e.lastUsed = cache.nextTimestamp
func epochAncestor(dag: ChainDAGRef, bid: BlockId, epoch: Epoch):
Opt[BlockSlotId] =
## The epoch ancestor is the last block that has an effect on the epoch-
## related state data, as updated in `process_epoch` - this block determines
## effective balances, validator addtions and removals etc and serves as a
## base for `EpochRef` construction.
if epoch < dag.tail.slot.epoch or bid.slot < dag.tail.slot:
# Not enough information in database to meaningfully process pre-tail epochs
return Opt.none BlockSlotId
let
dependentSlot =
if epoch == dag.tail.slot.epoch:
# Use the tail as "dependent block" - this may be the genesis block, or,
# in the case of checkpoint sync, the checkpoint block
dag.tail.slot
else:
epoch.start_slot() - 1
bsi = ? dag.atSlot(bid, dependentSlot)
epochSlot =
if epoch == dag.tail.slot.epoch:
dag.tail.slot
else:
epoch.start_slot()
ok BlockSlotId(bid: bsi.bid, slot: epochSlot)
func epochKey(dag: ChainDAGRef, bid: BlockId, epoch: Epoch): Opt[EpochKey] =
## The state transition works by storing information from blocks in a
## "working" area until the epoch transition, then batching work collected
## during the epoch. Thus, last block in the ancestor epochs is the block
## that has an impact on epoch currently considered.
##
## This function returns an epoch key pointing to that epoch boundary, i.e. the
## boundary where the last block has been applied to the state and epoch
## processing has been done.
let bsi = dag.epochAncestor(bid, epoch).valueOr:
return Opt.none(EpochKey)
Opt.some(EpochKey(bid: bsi.bid, epoch: epoch))
func putShufflingRef*(dag: ChainDAGRef, shufflingRef: ShufflingRef) =
## Store shuffling in the cache
if shufflingRef.epoch < dag.finalizedHead.slot.epoch():
# Only cache epoch information for unfinalized blocks - earlier states
# are seldomly used (ie RPC), so no need to cache
return
dag.shufflingRefs.put shufflingRef
func findShufflingRef*(
dag: ChainDAGRef, bid: BlockId, epoch: Epoch): Opt[ShufflingRef] =
## Lookup a shuffling in the cache, returning `none` if it's not present - see
## `getShufflingRef` for a version that creates a new instance if it's missing
let
dependent_slot = epoch.attester_dependent_slot()
dependent_bsi = ? dag.atSlot(bid, dependent_slot)
# Check `ShufflingRef` cache
let shufflingRef = dag.shufflingRefs.findIt(
it.epoch == epoch and it.attester_dependent_root == dependent_bsi.bid.root)
if shufflingRef.isOk:
return shufflingRef
# Check `EpochRef` cache
let epochRef = dag.epochRefs.peekIt(
it.shufflingRef.epoch == epoch and
it.shufflingRef.attester_dependent_root == dependent_bsi.bid.root)
if epochRef.isOk:
dag.putShufflingRef(epochRef.get.shufflingRef)
return ok epochRef.get.shufflingRef
err()
func findEpochRef*(
dag: ChainDAGRef, bid: BlockId, epoch: Epoch): Opt[EpochRef] =
## Lookup an EpochRef in the cache, returning `none` if it's not present - see
## `getEpochRef` for a version that creates a new instance if it's missing
let key = ? dag.epochKey(bid, epoch)
dag.epochRefs.findIt(it.key == key)
func putEpochRef(dag: ChainDAGRef, epochRef: EpochRef) =
if epochRef.epoch < dag.finalizedHead.slot.epoch():
# Only cache epoch information for unfinalized blocks - earlier states
# are seldomly used (ie RPC), so no need to cache
return
dag.epochRefs.put epochRef
func init*(
T: type ShufflingRef, state: ForkedHashedBeaconState,
cache: var StateCache, epoch: Epoch): T =
let attester_dependent_root =
withState(state): forkyState.dependent_root(epoch.get_previous_epoch)
ShufflingRef(
epoch: epoch,
attester_dependent_root: attester_dependent_root,
shuffled_active_validator_indices:
cache.get_shuffled_active_validator_indices(state, epoch),
)
func init*(
T: type EpochRef, dag: ChainDAGRef, state: ForkedHashedBeaconState,
cache: var StateCache): T =
let
epoch = state.get_current_epoch()
proposer_dependent_root = withState(state):
forkyState.proposer_dependent_root
shufflingRef = dag.findShufflingRef(state.latest_block_id, epoch).valueOr:
let tmp = ShufflingRef.init(state, cache, epoch)
dag.putShufflingRef(tmp)
tmp
total_active_balance = withState(state):
get_total_active_balance(forkyState.data, cache)
epochRef = EpochRef(
key: dag.epochKey(state.latest_block_id, epoch).expect(
"Valid epoch ancestor when processing state"),
eth1_data:
getStateField(state, eth1_data),
eth1_deposit_index:
getStateField(state, eth1_deposit_index),
checkpoints:
FinalityCheckpoints(
justified: getStateField(state, current_justified_checkpoint),
finalized: getStateField(state, finalized_checkpoint)),
# beacon_proposers: Separately filled below
proposer_dependent_root: proposer_dependent_root,
shufflingRef: shufflingRef,
total_active_balance: total_active_balance
)
epochStart = epoch.start_slot()
for i in 0'u64..<SLOTS_PER_EPOCH:
epochRef.beacon_proposers[i] =
get_beacon_proposer_index(state, cache, epochStart + i)
# When fork choice runs, it will need the effective balance of the justified
# checkpoint - we pre-load the balances here to avoid rewinding the justified
# state later and compress them because not all checkpoints end up being used
# for fork choice - specially during long periods of non-finalization
func snappyEncode(inp: openArray[byte]): seq[byte] =
try:
snappy.encode(inp)
except CatchableError as err:
raiseAssert err.msg
epochRef.effective_balances_bytes =
snappyEncode(SSZ.encode(
List[Gwei, Limit VALIDATOR_REGISTRY_LIMIT](
get_effective_balances(getStateField(state, validators).asSeq, epoch))))
epochRef
func loadStateCache(
dag: ChainDAGRef, cache: var StateCache, bid: BlockId, epoch: Epoch) =
# When creating a state cache, we want the current and the previous epoch
# information to be preloaded as both of these are used in state transition
# functions
template load(e: Epoch) =
block:
let epoch = e
if epoch notin cache.shuffled_active_validator_indices:
let shufflingRef = dag.findShufflingRef(bid, epoch)
if shufflingRef.isSome():
cache.shuffled_active_validator_indices[epoch] =
shufflingRef[][].shuffled_active_validator_indices
let epochRef = dag.findEpochRef(bid, epoch)
if epochRef.isSome():
let start_slot = epoch.start_slot()
for i, idx in epochRef[][].beacon_proposers:
cache.beacon_proposer_indices[start_slot + i] = idx
cache.total_active_balance[epoch] = epochRef[][].total_active_balance
load(epoch)
if epoch > 0:
load(epoch - 1)
if dag.head != nil: # nil during init.. sigh
let period = dag.head.slot.sync_committee_period
if period == epoch.sync_committee_period and
period notin cache.sync_committees and
period > dag.cfg.ALTAIR_FORK_EPOCH.sync_committee_period():
# If the block we're aiming for shares ancestry with head, we can reuse
# the cached head committee - this accounts for most "live" cases like
# syncing and checking blocks since the committees rarely change
let periodBsi = dag.atSlot(bid, period.start_slot)
if periodBsi.isSome and periodBsi ==
dag.atSlot(dag.head.bid, period.start_slot):
# We often end up sharing sync committees with head during sync / gossip
# validation / head updates
cache.sync_committees[period] = dag.headSyncCommittees
func containsForkBlock*(dag: ChainDAGRef, root: Eth2Digest): bool =
## Checks for blocks at the finalized checkpoint or newer
KeyedBlockRef.asLookupKey(root) in dag.forkBlocks
func isFinalizedStateSnapshot(slot: Slot): bool =
slot.is_epoch and slot.epoch mod EPOCHS_PER_STATE_SNAPSHOT == 0
func isStateCheckpoint(dag: ChainDAGRef, bsi: BlockSlotId): bool =
## State checkpoints are the points in time for which we store full state
## snapshots, which later serve as rewind starting points when replaying state
## transitions from database, for example during reorgs.
##
# As a policy, we only store epoch boundary states without the epoch block
# (if it exists) applied - the rest can be reconstructed by loading an epoch
# boundary state and applying the missing blocks.
# We also avoid states that were produced with empty slots only - as such,
# there is only a checkpoint for the first epoch after a block.
# The tail block also counts as a state checkpoint!
(bsi.isProposed and bsi.bid == dag.tail) or
(bsi.slot.is_epoch and bsi.slot.epoch == (bsi.bid.slot.epoch + 1))
proc getState(
db: BeaconChainDB, cfg: RuntimeConfig, block_root: Eth2Digest, slot: Slot,
state: var ForkedHashedBeaconState, rollback: RollbackProc): bool =
let state_root = db.getStateRoot(block_root, slot).valueOr:
return false
db.getState(cfg.consensusForkAtEpoch(slot.epoch), state_root, state, rollback)
proc containsState*(
db: BeaconChainDB, cfg: RuntimeConfig, block_root: Eth2Digest,
slots: Slice[Slot], legacy = true): bool =
var slot = slots.b
while slot >= slots.a:
let state_root = db.getStateRoot(block_root, slot)
if state_root.isSome() and
db.containsState(
cfg.consensusForkAtEpoch(slot.epoch), state_root.get(), legacy):
return true
if slot == slots.a: # avoid underflow at genesis
break
slot -= 1
false
proc getState*(
db: BeaconChainDB, cfg: RuntimeConfig, block_root: Eth2Digest,
slots: Slice[Slot], state: var ForkedHashedBeaconState,
rollback: RollbackProc): bool =
var slot = slots.b
while slot >= slots.a:
let state_root = db.getStateRoot(block_root, slot)
if state_root.isSome() and
db.getState(
cfg.consensusForkAtEpoch(slot.epoch), state_root.get(), state,
rollback):
return true
if slot == slots.a: # avoid underflow at genesis
break
slot -= 1
false
proc getState(
dag: ChainDAGRef, bsi: BlockSlotId, state: var ForkedHashedBeaconState): bool =
## Load a state from the database given a block and a slot - this will first
## lookup the state root in the state root table then load the corresponding
## state, if it exists
if not dag.isStateCheckpoint(bsi):
return false
let rollbackAddr =
# Any restore point will do as long as it's not the object being updated
if unsafeAddr(state) == unsafeAddr(dag.headState):
unsafeAddr dag.clearanceState
else:
unsafeAddr dag.headState
let v = addr state
func rollback() =
assign(v[], rollbackAddr[])
dag.db.getState(dag.cfg, bsi.bid.root, bsi.slot, state, rollback)
proc getStateByParent(
dag: ChainDAGRef, bid: BlockId, state: var ForkedHashedBeaconState): bool =
## Try to load the state referenced by the parent of the given `bid` - this
## state can be used to advance to the `bid` state itself.
let slot = bid.slot
let
summary = dag.db.getBeaconBlockSummary(bid.root).valueOr:
return false
parentMinSlot =
dag.db.getBeaconBlockSummary(summary.parent_root).
map(proc(x: auto): auto = x.slot).valueOr:
# in the cases that we don't have slot information, we'll search for the
# state for a few back from the `bid` slot - if there are gaps of empty
# slots larger than this, we will not be able to load the state using this
# trick
if slot.uint64 >= (EPOCHS_PER_STATE_SNAPSHOT * 2) * SLOTS_PER_EPOCH:
slot - (EPOCHS_PER_STATE_SNAPSHOT * 2) * SLOTS_PER_EPOCH
else:
Slot(0)
let rollbackAddr =
# Any restore point will do as long as it's not the object being updated
if unsafeAddr(state) == unsafeAddr(dag.headState):
unsafeAddr dag.clearanceState
else:
unsafeAddr dag.headState
let v = addr state
func rollback() =
assign(v[], rollbackAddr[])
dag.db.getState(
dag.cfg, summary.parent_root, parentMinSlot..slot, state, rollback)
proc getNearbyState(
dag: ChainDAGRef, state: var ForkedHashedBeaconState, bid: BlockId,
lowSlot: Slot): Opt[void] =
## Load state from DB that is close to `bid` and has at least slot `lowSlot`.
var
e = bid.slot.epoch
b = bid
while true:
let stateSlot = e.start_slot
if stateSlot < lowSlot:
return err()
b = (? dag.atSlot(b, max(stateSlot, 1.Slot) - 1)).bid
let bsi = BlockSlotId.init(b, stateSlot)
if not dag.getState(bsi, state):
if e == GENESIS_EPOCH:
return err()
dec e
continue
return ok()
proc currentSyncCommitteeForPeriod*(
dag: ChainDAGRef,
tmpState: var ForkedHashedBeaconState,
period: SyncCommitteePeriod): Opt[SyncCommittee] =
## Fetch a `SyncCommittee` for a given sync committee period.
## For non-finalized periods, follow the chain as selected by fork choice.
let lowSlot = max(dag.tail.slot, dag.cfg.ALTAIR_FORK_EPOCH.start_slot)
if period < lowSlot.sync_committee_period:
return err()
let
periodStartSlot = period.start_slot
syncCommitteeSlot = max(periodStartSlot, lowSlot)
bsi = ? dag.getBlockIdAtSlot(syncCommitteeSlot)
dag.withUpdatedState(tmpState, bsi) do:
withState(updatedState):
when consensusFork >= ConsensusFork.Altair:
ok forkyState.data.current_sync_committee
else: err()
do: err()
proc getBlockIdAtSlot*(
dag: ChainDAGRef, state: ForkyHashedBeaconState, slot: Slot): Opt[BlockId] =
if slot >= state.data.slot:
Opt.some state.latest_block_id
elif state.data.slot <= slot + SLOTS_PER_HISTORICAL_ROOT:
dag.getBlockId(state.data.get_block_root_at_slot(slot))
else:
Opt.none(BlockId)
proc updateBeaconMetrics(
state: ForkedHashedBeaconState, bid: BlockId, cache: var StateCache) =
# https://github.com/ethereum/beacon-metrics/blob/master/metrics.md#additional-metrics
# both non-negative, so difference can't overflow or underflow int64
beacon_head_root.set(bid.root.toGaugeValue)
beacon_head_slot.set(bid.slot.toGaugeValue)
withState(state):
beacon_pending_deposits.set(
(forkyState.data.eth1_data.deposit_count -
forkyState.data.eth1_deposit_index).toGaugeValue)
beacon_processed_deposits_total.set(
forkyState.data.eth1_deposit_index.toGaugeValue)
beacon_current_justified_epoch.set(
forkyState.data.current_justified_checkpoint.epoch.toGaugeValue)
beacon_current_justified_root.set(
forkyState.data.current_justified_checkpoint.root.toGaugeValue)
beacon_previous_justified_epoch.set(
forkyState.data.previous_justified_checkpoint.epoch.toGaugeValue)
beacon_previous_justified_root.set(
forkyState.data.previous_justified_checkpoint.root.toGaugeValue)
beacon_finalized_epoch.set(
forkyState.data.finalized_checkpoint.epoch.toGaugeValue)
beacon_finalized_root.set(
forkyState.data.finalized_checkpoint.root.toGaugeValue)
let active_validators = count_active_validators(
forkyState.data, forkyState.data.slot.epoch, cache).toGaugeValue
beacon_active_validators.set(active_validators)
beacon_current_active_validators.set(active_validators)
import blockchain_dag_light_client
export
blockchain_dag_light_client.getLightClientBootstrap,
blockchain_dag_light_client.getLightClientUpdateForPeriod,
blockchain_dag_light_client.getLightClientFinalityUpdate,
blockchain_dag_light_client.getLightClientOptimisticUpdate
proc putState(dag: ChainDAGRef, state: ForkedHashedBeaconState, bid: BlockId) =
# Store a state and its root
let slot = getStateField(state, slot)
logScope:
blck = shortLog(bid)
stateSlot = shortLog(slot)
stateRoot = shortLog(getStateRoot(state))
if not dag.isStateCheckpoint(BlockSlotId.init(bid, slot)):
return
# Don't consider legacy tables here, they are slow to read so we'll want to
# rewrite things in the new table anyway.
if dag.db.containsState(
dag.cfg.consensusForkAtEpoch(slot.epoch), getStateRoot(state),
legacy = false):
return
let startTick = Moment.now()
# Ideally we would save the state and the root lookup cache in a single
# transaction to prevent database inconsistencies, but the state loading code
# is resilient against one or the other going missing
withState(state):
dag.db.putState(forkyState)
debug "Stored state", putStateDur = Moment.now() - startTick
proc advanceSlots*(
dag: ChainDAGRef, state: var ForkedHashedBeaconState, slot: Slot, save: bool,
cache: var StateCache, info: var ForkedEpochInfo) =
# Given a state, advance it zero or more slots by applying empty slot
# processing - the state must be positioned at or before `slot`
doAssert getStateField(state, slot) <= slot
let stateBid = state.latest_block_id
while getStateField(state, slot) < slot:
let
preEpoch = getStateField(state, slot).epoch
loadStateCache(dag, cache, stateBid, getStateField(state, slot).epoch)
process_slots(
dag.cfg, state, getStateField(state, slot) + 1, cache, info,
dag.updateFlags).expect("process_slots shouldn't fail when state slot is correct")
if save:
dag.putState(state, stateBid)
# The reward information in the state transition is computed for epoch
# transitions - when transitioning into epoch N, the activities in epoch
# N-2 are translated into balance updates, and this is what we capture
# in the monitor. This may be inaccurate during a deep reorg (>1 epoch)
# which is an acceptable tradeoff for monitoring.
withState(state):
let postEpoch = forkyState.data.slot.epoch
if preEpoch != postEpoch and postEpoch >= 2:
var proposers: array[SLOTS_PER_EPOCH, Opt[ValidatorIndex]]
let epochRef = dag.findEpochRef(stateBid, postEpoch - 2)
if epochRef.isSome():
proposers = epochRef[][].beacon_proposers
dag.validatorMonitor[].registerEpochInfo(
forkyState.data, proposers, info)
proc applyBlock(
dag: ChainDAGRef, state: var ForkedHashedBeaconState, bid: BlockId,
cache: var StateCache, info: var ForkedEpochInfo): Result[void, cstring] =
loadStateCache(dag, cache, bid, getStateField(state, slot).epoch)
case dag.cfg.consensusForkAtEpoch(bid.slot.epoch)
of ConsensusFork.Phase0:
let data = getBlock(dag, bid, phase0.TrustedSignedBeaconBlock).valueOr:
return err("Block load failed")
state_transition(
dag.cfg, state, data, cache, info,
dag.updateFlags + {slotProcessed}, noRollback)
of ConsensusFork.Altair:
let data = getBlock(dag, bid, altair.TrustedSignedBeaconBlock).valueOr:
return err("Block load failed")
state_transition(
dag.cfg, state, data, cache, info,
dag.updateFlags + {slotProcessed}, noRollback)
of ConsensusFork.Bellatrix:
let data = getBlock(dag, bid, bellatrix.TrustedSignedBeaconBlock).valueOr:
return err("Block load failed")
state_transition(
dag.cfg, state, data, cache, info,
dag.updateFlags + {slotProcessed}, noRollback)
of ConsensusFork.Capella:
let data = getBlock(dag, bid, capella.TrustedSignedBeaconBlock).valueOr:
return err("Block load failed")
state_transition(
dag.cfg, state, data, cache, info,
dag.updateFlags + {slotProcessed}, noRollback)
of ConsensusFork.Deneb:
let data = getBlock(dag, bid, deneb.TrustedSignedBeaconBlock).valueOr:
return err("Block load failed")
state_transition(
dag.cfg, state, data, cache, info,
dag.updateFlags + {slotProcessed}, noRollback)
proc init*(T: type ChainDAGRef, cfg: RuntimeConfig, db: BeaconChainDB,
validatorMonitor: ref ValidatorMonitor, updateFlags: UpdateFlags,
eraPath = ".",
onBlockCb: OnBlockCallback = nil, onHeadCb: OnHeadCallback = nil,
onReorgCb: OnReorgCallback = nil, onFinCb: OnFinalizedCallback = nil,
vanityLogs = default(VanityLogs),
lcDataConfig = default(LightClientDataConfig)): ChainDAGRef =
cfg.checkForkConsistency()
doAssert updateFlags - {strictVerification} == {},
"Other flags not supported in ChainDAG"
# TODO we require that the db contains both a head and a tail block -
# asserting here doesn't seem like the right way to go about it however..
# Tail is the first block for which we can construct a state - either
# genesis or a checkpoint
let
startTick = Moment.now()
genesisRoot = db.getGenesisBlock()
tailRoot = db.getTailBlock().expect(
"preInit should have initialized the database with a tail block root")
tail = db.getBlockId(tailRoot).expect(
"tail block summary in database, database corrupt?")
headRoot = db.getHeadBlock().expect("head root, database corrupt?")
head = db.getBlockId(headRoot).expect("head block id, database corrupt?")
# Have to be careful with this instance, it is not yet fully initialized so
# as to avoid having to allocate a separate "init" state
dag = ChainDAGRef(
db: db,
validatorMonitor: validatorMonitor,
genesis: genesisRoot.map(
proc(x: auto): auto = BlockId(root: x, slot: GENESIS_SLOT)),
tail: tail,
# The only allowed flag right now is strictVerification, as the others all
# allow skipping some validation.
updateFlags: updateFlags * {strictVerification},
cfg: cfg,
vanityLogs: vanityLogs,
lcDataStore: initLightClientDataStore(
lcDataConfig, cfg, db.getLightClientDataDB()),
onBlockAdded: onBlockCb,
onHeadChanged: onHeadCb,
onReorgHappened: onReorgCb,
onFinHappened: onFinCb,
)
loadTick = Moment.now()
var
headRef, curRef: BlockRef
# When starting from a checkpoint with an empty block, we'll store the state
# "ahead" of the head slot - this slot would be considered finalized
slot = max(head.slot, (tail.slot.epoch + 1).start_slot)
# To know the finalized checkpoint of the head, we need to recreate its
# state - the tail is implicitly finalized, and if we have a finalized block
# table, that provides another hint
finalizedSlot = db.finalizedBlocks.high.get(tail.slot)
cache: StateCache
foundHeadState = false
headBlocks: seq[BlockRef]
# Load head -> finalized, or all summaries in case the finalized block table
# hasn't been written yet
for blck in db.getAncestorSummaries(head.root):
# The execution block root gets filled in as needed. Nonfinalized Bellatrix
# and later blocks are loaded as optimistic, which gets adjusted that first
# `VALID` fcU from an EL plus markBlockVerified. Pre-merge blocks still get
# marked as `VALID`.
let newRef = BlockRef.init(
blck.root, Opt.none Eth2Digest, executionValid = false,
blck.summary.slot)
if headRef == nil:
headRef = newRef
if curRef != nil:
link(newRef, curRef)
curRef = newRef
dag.forkBlocks.incl(KeyedBlockRef.init(curRef))
if not foundHeadState:
foundHeadState = db.getState(
cfg, blck.root, blck.summary.slot..slot, dag.headState, noRollback)
slot = blck.summary.slot
if not foundHeadState:
# When the database has been written with a pre-fork version of the
# software, it may happen that blocks produced using an "unforked"
# chain get written to the database - we need to skip such blocks
# when loading the database with a fork-compatible version
if containsBlock(cfg, db, curRef.slot, curRef.root):
headBlocks.add curRef
else:
if headBlocks.len > 0:
fatal "Missing block needed to create head state, database corrupt?",
curRef = shortLog(curRef)
quit 1
# Without the block data we can't form a state for this root, so
# we'll need to move the head back
headRef = nil
dag.forkBlocks.excl(KeyedBlockRef.init(curRef))
if curRef.slot <= finalizedSlot:
# Only non-finalized slots get a `BlockRef`
break
let summariesTick = Moment.now()
if not foundHeadState:
if not dag.getStateByParent(curRef.bid, dag.headState):
fatal "Could not load head state, database corrupt?",
head = shortLog(head), tail = shortLog(dag.tail)
quit 1
withState(dag.headState):
when consensusFork >= ConsensusFork.Altair:
dag.headSyncCommittees = forkyState.data.get_sync_committee_cache(cache)
block:
# EpochRef needs an epoch boundary state
assign(dag.epochRefState, dag.headState)
var info: ForkedEpochInfo
while headBlocks.len > 0:
dag.applyBlock(
dag.headState, headBlocks.pop().bid, cache,
info).expect("head blocks should apply")
dag.head = headRef
dag.heads = @[headRef]
assign(dag.clearanceState, dag.headState)
if dag.headState.latest_block_root == tail.root:
# In case we started from a checkpoint with an empty slot
finalizedSlot = getStateField(dag.headState, slot)
finalizedSlot =
max(
finalizedSlot,
getStateField(dag.headState, finalized_checkpoint).epoch.start_slot)
let
configFork = case dag.headState.kind
of ConsensusFork.Phase0: genesisFork(cfg)
of ConsensusFork.Altair: altairFork(cfg)
of ConsensusFork.Bellatrix: bellatrixFork(cfg)
of ConsensusFork.Capella: capellaFork(cfg)
of ConsensusFork.Deneb: denebFork(cfg)
stateFork = getStateField(dag.headState, fork)
# Here, we check only the `current_version` field because the spec
# mandates that testnets starting directly from a particular fork
# should have `previous_version` set to `current_version` while
# this doesn't happen to be the case in network that go through
# regular hard-fork upgrades. See for example:
# https://github.com/ethereum/consensus-specs/blob/v1.4.0-beta.6/specs/bellatrix/beacon-chain.md#testing
if stateFork.current_version != configFork.current_version:
error "State from database does not match network, check --network parameter",
tail = dag.tail, headRef, stateFork, configFork
quit 1
# Need to load state to find genesis validators root, before loading era db
dag.era = EraDB.new(
cfg, eraPath, getStateField(dag.headState, genesis_validators_root))
# We used an interim finalizedHead while loading the head state above - now
# that we have loaded the dag up to the finalized slot, we can also set
# finalizedHead to its real value
dag.finalizedHead = headRef.atSlot(finalizedSlot)
dag.lastPrunePoint = dag.finalizedHead.toBlockSlotId().expect("not nil")
doAssert dag.finalizedHead.blck != nil,
"The finalized head should exist at the slot"
block: # Top up finalized blocks
if db.finalizedBlocks.high.isNone or
db.finalizedBlocks.high.get() < dag.finalizedHead.blck.slot:
# Versions prior to 1.7.0 did not store finalized blocks in the
# database, and / or the application might have crashed between the head
# and finalized blocks updates.
info "Loading finalized blocks",
finHigh = db.finalizedBlocks.high,
finalizedHead = shortLog(dag.finalizedHead)
var
newFinalized: seq[BlockId]
tmp = dag.finalizedHead.blck
while tmp.parent != nil:
newFinalized.add(tmp.bid)
let p = tmp.parent
tmp.parent = nil
tmp = p
for blck in db.getAncestorSummaries(tmp.root):
if db.finalizedBlocks.high.isSome and
blck.summary.slot <= db.finalizedBlocks.high.get:
break
newFinalized.add(BlockId(slot: blck.summary.slot, root: blck.root))
db.updateFinalizedBlocks(newFinalized)
doAssert dag.finalizedHead.blck.parent == nil,
"The finalized head is the last BlockRef with a parent"
block:
let finalized = db.finalizedBlocks.get(db.finalizedBlocks.high.get()).expect(
"tail at least")
if finalized != dag.finalizedHead.blck.root:
error "Head does not lead to finalized block, database corrupt?",
head = shortLog(head), finalizedHead = shortLog(dag.finalizedHead),
tail = shortLog(dag.tail), finalized = shortLog(finalized)
quit 1
dag.backfill = block:
let backfillSlot = db.finalizedBlocks.low.expect("tail at least")
if backfillSlot <= dag.horizon:
# Backfill done, no need to load anything
BeaconBlockSummary()
elif backfillSlot < dag.tail.slot:
let backfillRoot = db.finalizedBlocks.get(backfillSlot).expect(
"low to be loadable")
db.getBeaconBlockSummary(backfillRoot).expect(
"Backfill block must have a summary: " & $backfillRoot)
elif dag.containsBlock(dag.tail):
db.getBeaconBlockSummary(dag.tail.root).expect(
"Tail block must have a summary: " & $dag.tail.root)
else:
# Checkpoint sync, checkpoint block unavailable
BeaconBlockSummary(
slot: dag.tail.slot + 1,
parent_root: dag.tail.root)
dag.forkDigests = newClone ForkDigests.init(
cfg, getStateField(dag.headState, genesis_validators_root))
withState(dag.headState):
dag.validatorMonitor[].registerState(forkyState.data)
updateBeaconMetrics(dag.headState, dag.head.bid, cache)
let finalizedTick = Moment.now()
if dag.backfill.slot > GENESIS_SLOT: # Try frontfill from era files
let backfillSlot = dag.backfill.slot - 1
dag.frontfillBlocks = newSeqOfCap[Eth2Digest](backfillSlot.int)
let
historical_roots = getStateField(dag.headState, historical_roots).asSeq()
historical_summaries = dag.headState.historical_summaries.asSeq()
var
blocks = 0
# Here, we'll build up the slot->root mapping in memory for the range of
# blocks from genesis to backfill, if possible.
for bid in dag.era.getBlockIds(
historical_roots, historical_summaries, Slot(0), Eth2Digest()):
if bid.slot >= backfillSlot:
# If we end up in here, we failed the root comparison just below in
# an earlier iteration
fatal "Era summaries don't lead up to backfill, database or era files corrupt?",
bid
quit 1
# In BeaconState.block_roots, empty slots are filled with the root of
# the previous block - in our data structure, we use a zero hash instead
dag.frontfillBlocks.setLen(bid.slot.int + 1)
dag.frontfillBlocks[bid.slot.int] = bid.root
if bid.root == dag.backfill.parent_root:
# We've reached the backfill point, meaning blocks are available
# in the sqlite database from here onwards - remember this point in
# time so that we can write summaries to the database - it's a lot
# faster to load from database than to iterate over era files with
# the current naive era file reader.
reset(dag.backfill)
dag.updateFrontfillBlocks()
break
blocks += 1
if blocks > 0:
info "Front-filled blocks from era files", blocks
let frontfillTick = Moment.now()
# Fill validator key cache in case we're loading an old database that doesn't
# have a cache
dag.updateValidatorKeys(getStateField(dag.headState, validators).asSeq())
# Initialize pruning such that when starting with a database that hasn't been
# pruned, we work our way from the tail to the horizon in incremental steps
dag.lastHistoryPruneHorizon = dag.horizon()
dag.lastHistoryPruneBlockHorizon = block:
let boundary = min(dag.tail.slot, dag.horizon())
if boundary.epoch() >= EPOCHS_PER_STATE_SNAPSHOT:
start_slot(boundary.epoch() - EPOCHS_PER_STATE_SNAPSHOT)
else:
Slot(0)
info "Block DAG initialized",
head = shortLog(dag.head),
finalizedHead = shortLog(dag.finalizedHead),
tail = shortLog(dag.tail),
backfill = shortLog(dag.backfill),
loadDur = loadTick - startTick,
summariesDur = summariesTick - loadTick,
finalizedDur = finalizedTick - summariesTick,
frontfillDur = frontfillTick - finalizedTick,
keysDur = Moment.now() - frontfillTick
dag.initLightClientDataCache()
dag
template genesis_validators_root*(dag: ChainDAGRef): Eth2Digest =
getStateField(dag.headState, genesis_validators_root)
proc genesisBlockRoot*(dag: ChainDAGRef): Eth2Digest =
dag.db.getGenesisBlock().expect("DB must be initialized with genesis block")
func getEpochRef*(
dag: ChainDAGRef, state: ForkedHashedBeaconState, cache: var StateCache): EpochRef =
## Get a cached `EpochRef` or construct one based on the given state - always
## returns an EpochRef instance
let
bid = state.latest_block_id
epoch = state.get_current_epoch()
dag.findEpochRef(bid, epoch).valueOr:
let res = EpochRef.init(dag, state, cache)
dag.putEpochRef(res)
res
proc getEpochRef*(
dag: ChainDAGRef, bid: BlockId, epoch: Epoch,
preFinalized: bool): Result[EpochRef, cstring] =
## Return a cached EpochRef or construct one from the database, if possible -
## returns `none` on failure.
##
## When `preFinalized` is true, include epochs from before the finalized
## checkpoint in the search - this potentially can result in long processing
## times due to state replays.
##
## Requests for epochs >= dag.finalizedHead.slot.epoch always return an
## instance. One must be careful to avoid race conditions in `async` code
## where the finalized head might change during an `await`.
##
## Requests for epochs < dag.finalizedHead.slot.epoch may fail, either because
## the search was limited by the `preFinalized` flag or because state history
## has been pruned - `none` will be returned in this case.
if not preFinalized and epoch < dag.finalizedHead.slot.epoch:
return err("Requesting pre-finalized EpochRef")
if bid.slot < dag.tail.slot or epoch < dag.tail.slot.epoch:
return err("Requesting EpochRef for pruned state")
let epochRef = dag.findEpochRef(bid, epoch)
if epochRef.isOk():
beacon_state_data_cache_hits.inc
return ok epochRef.get()
beacon_state_data_cache_misses.inc
let
ancestor = dag.epochAncestor(bid, epoch).valueOr:
# If we got in here, the bid must be unknown or we would have gotten
# _some_ ancestor (like the tail)
return err("Requesting EpochRef for non-canonical block")
var cache: StateCache
if not updateState(dag, dag.epochRefState, ancestor, false, cache):
return err("Could not load requested state")
ok(dag.getEpochRef(dag.epochRefState, cache))
proc getEpochRef*(
dag: ChainDAGRef, blck: BlockRef, epoch: Epoch,
preFinalized: bool): Result[EpochRef, cstring] =
dag.getEpochRef(blck.bid, epoch, preFinalized)
proc getFinalizedEpochRef*(dag: ChainDAGRef): EpochRef =
dag.getEpochRef(
dag.finalizedHead.blck, dag.finalizedHead.slot.epoch, false).expect(
"getEpochRef for finalized head should always succeed")
proc ancestorSlot*(
dag: ChainDAGRef, state: ForkyHashedBeaconState, bid: BlockId,
lowSlot: Slot): Opt[Slot] =
## Return common ancestor slot of `bid` and `state`, if at least `lowSlot`.
## Return `none` if no common ancestor is found with slot >= `lowSlot`.
if state.data.slot < lowSlot or bid.slot < lowSlot:
return Opt.none(Slot)
var stateBid = ? dag.getBlockIdAtSlot(state, bid.slot)
if stateBid.slot < lowSlot:
return Opt.none(Slot)
var blockBid = (? dag.atSlot(bid, stateBid.slot)).bid
if blockBid.slot < lowSlot:
return Opt.none(Slot)
while stateBid != blockBid:
if stateBid.slot >= blockBid.slot:
stateBid = ? dag.getBlockIdAtSlot(
state, min(blockBid.slot, stateBid.slot - 1))
if stateBid.slot < lowSlot:
return Opt.none(Slot)
else:
blockBid = ? dag.parent(blockBid)
if blockBid.slot < lowSlot:
return Opt.none(Slot)
Opt.some stateBid.slot
proc computeRandaoMix(
bdata: ForkedTrustedSignedBeaconBlock): Opt[Eth2Digest] =
## Compute the requested RANDAO mix for `bdata` without `state`, if possible.
withBlck(bdata):
when consensusFork >= ConsensusFork.Bellatrix:
if forkyBlck.message.is_execution_block:
var mix = eth2digest(forkyBlck.message.body.randao_reveal.toRaw())
mix.data.mxor forkyBlck.message.body.execution_payload.prev_randao.data
return ok mix
Opt.none(Eth2Digest)
proc computeRandaoMix*(
dag: ChainDAGRef, state: ForkyHashedBeaconState, bid: BlockId,
lowSlot: Slot): Opt[Eth2Digest] =
## Compute the requested RANDAO mix for `bid` based on `state`.
## Return `none` if `state` and `bid` do not share a common ancestor
## with slot >= `lowSlot`.
let ancestorSlot = ? dag.ancestorSlot(state, bid, lowSlot)
doAssert ancestorSlot <= state.data.slot
doAssert ancestorSlot <= bid.slot
# If `blck` is post merge, RANDAO information is immediately available
let
bdata = ? dag.getForkedBlock(bid)
fullMix = computeRandaoMix(bdata)
if fullMix.isSome:
return fullMix
# RANDAO mix has to be recomputed from `bid` and `state`
var mix {.noinit.}: Eth2Digest
proc mixToAncestor(highBid: BlockId): Opt[void] =
## Mix in/out RANDAO reveals back to `ancestorSlot`
var bid = highBid
while bid.slot > ancestorSlot:
let bdata = ? dag.getForkedBlock(bid)
withBlck(bdata): # See `process_randao` / `process_randao_mixes_reset`
mix.data.mxor eth2digest(
forkyBlck.message.body.randao_reveal.toRaw()).data
bid = ? dag.parent(bid)
ok()
# Mix in RANDAO from `bid`
if ancestorSlot < bid.slot:
withBlck(bdata):
mix = eth2digest(forkyBlck.message.body.randao_reveal.toRaw())
? mixToAncestor(? dag.parent(bid))
else:
mix.reset()
# Mix in RANDAO from `state`
let ancestorEpoch = ancestorSlot.epoch
if ancestorEpoch + EPOCHS_PER_HISTORICAL_VECTOR <= state.data.slot.epoch:
return Opt.none(Eth2Digest)
let mixRoot = state.dependent_root(ancestorEpoch + 1)
if mixRoot.isZero:
return Opt.none(Eth2Digest)
? mixToAncestor(? dag.getBlockId(mixRoot))
mix.data.mxor state.data.get_randao_mix(ancestorEpoch).data
ok mix
proc computeRandaoMixFromMemory*(
dag: ChainDAGRef, bid: BlockId, lowSlot: Slot): Opt[Eth2Digest] =
## Compute requested RANDAO mix for `bid` from available states (~5 ms).
template tryWithState(state: ForkedHashedBeaconState) =
block:
withState(state):
let mix = dag.computeRandaoMix(forkyState, bid, lowSlot)
if mix.isSome:
return mix
tryWithState dag.headState
tryWithState dag.epochRefState
tryWithState dag.clearanceState
proc computeRandaoMixFromDatabase*(
dag: ChainDAGRef, bid: BlockId, lowSlot: Slot): Opt[Eth2Digest] =
## Compute requested RANDAO mix for `bid` using closest DB state (~500 ms).
let state = assignClone(dag.headState)
? dag.getNearbyState(state[], bid, lowSlot)
withState(state[]):
dag.computeRandaoMix(forkyState, bid, lowSlot)
proc computeRandaoMix(
dag: ChainDAGRef, bid: BlockId, lowSlot: Slot): Opt[Eth2Digest] =
# Try to compute from states available in memory
let mix = dag.computeRandaoMixFromMemory(bid, lowSlot)
if mix.isSome:
return mix
# If `blck` is post merge, RANDAO information is immediately available
let
bdata = ? dag.getForkedBlock(bid)
fullMix = computeRandaoMix(bdata)
if fullMix.isSome:
return fullMix
# Fall back to database
dag.computeRandaoMixFromDatabase(bid, lowSlot)
proc computeRandaoMix*(dag: ChainDAGRef, bid: BlockId): Opt[Eth2Digest] =
## Compute requested RANDAO mix for `bid`.
const maxSlotDistance = SLOTS_PER_HISTORICAL_ROOT
let lowSlot = max(bid.slot, maxSlotDistance.Slot) - maxSlotDistance
dag.computeRandaoMix(bid, lowSlot)
proc lowSlotForAttesterShuffling*(epoch: Epoch): Slot =
## Return minimum slot that a state must share ancestry with a block history
## so that RANDAO at `epoch.attester_dependent_slot` can be computed.
# A state must be somewhat recent so that `get_active_validator_indices`
# for the queried `epoch` cannot be affected by any such skipped processing.
const numDelayEpochs = compute_activation_exit_epoch(GENESIS_EPOCH).uint64
let lowEpoch = max(epoch, (numDelayEpochs - 1).Epoch) - (numDelayEpochs - 1)
lowEpoch.start_slot
proc computeShufflingRef*(
dag: ChainDAGRef, state: ForkyHashedBeaconState,
blck: BlockRef, epoch: Epoch): Opt[ShufflingRef] =
## Compute `ShufflingRef` for `blck@epoch` based on `state`.
## If `state` has unviable `get_active_validator_indices`, return `none`.
let
dependentBid = (? dag.atSlot(blck.bid, epoch.attester_dependent_slot)).bid
lowSlot = epoch.lowSlotForAttesterShuffling
mix = ? dag.computeRandaoMix(state, dependentBid, lowSlot)
return ok ShufflingRef(
epoch: epoch,
attester_dependent_root: dependentBid.root,
shuffled_active_validator_indices:
state.data.get_shuffled_active_validator_indices(epoch, mix))
proc computeShufflingRefFromMemory*(
dag: ChainDAGRef, blck: BlockRef, epoch: Epoch): Opt[ShufflingRef] =
## Compute `ShufflingRef` from available states (~5 ms).
template tryWithState(state: ForkedHashedBeaconState) =
block:
withState(state):
let shufflingRef = dag.computeShufflingRef(forkyState, blck, epoch)
if shufflingRef.isOk:
return shufflingRef
tryWithState dag.headState
tryWithState dag.epochRefState
tryWithState dag.clearanceState
proc getShufflingRef*(
dag: ChainDAGRef, blck: BlockRef, epoch: Epoch,
preFinalized: bool): Opt[ShufflingRef] =
## Return the shuffling in the given history and epoch - this potentially is
## faster than returning a full EpochRef because the shuffling is determined
## an epoch in advance and therefore is less sensitive to reorgs
var shufflingRef = dag.findShufflingRef(blck.bid, epoch)
if shufflingRef.isSome:
return shufflingRef
# Use existing states to quickly compute the shuffling
shufflingRef = dag.computeShufflingRefFromMemory(blck, epoch)
if shufflingRef.isSome:
dag.putShufflingRef(shufflingRef.get)
return shufflingRef
# Last resort, this can take several seconds as this may replay states
let epochRef = dag.getEpochRef(blck, epoch, preFinalized).valueOr:
return Opt.none ShufflingRef
dag.putShufflingRef(epochRef.shufflingRef)
Opt.some epochRef.shufflingRef
func stateCheckpoint*(dag: ChainDAGRef, bsi: BlockSlotId): BlockSlotId =
## The first ancestor BlockSlot that is a state checkpoint
var bsi = bsi
while not dag.isStateCheckpoint(bsi):
if bsi.isProposed:
bsi.bid = dag.parent(bsi.bid).valueOr:
break
else:
bsi.slot = bsi.slot - 1
bsi
template forkAtEpoch*(dag: ChainDAGRef, epoch: Epoch): Fork =
forkAtEpoch(dag.cfg, epoch)
proc getBlockRange*(
dag: ChainDAGRef, startSlot: Slot, skipStep: uint64,
output: var openArray[BlockId]): Natural =
## This function populates an `output` buffer of blocks
## with a slots ranging from `startSlot` up to, but not including,
## `startSlot + skipStep * output.len`, skipping any slots that don't have
## a block.
##
## Blocks will be written to `output` from the end without gaps, even if
## a block is missing in a particular slot. The return value shows how
## many slots were missing blocks - to iterate over the result, start
## at this index.
##
## If there were no blocks in the range, `output.len` will be returned.
let
requestedCount = output.lenu64
headSlot = dag.head.slot
trace "getBlockRange entered",
head = shortLog(dag.head.root), requestedCount, startSlot, skipStep, headSlot
if startSlot < dag.backfill.slot:
debug "Got request for pre-backfill slot",
startSlot, backfillSlot = dag.backfill.slot, horizonSlot = dag.horizon
return output.len
if headSlot <= startSlot or requestedCount == 0:
return output.len # Identical to returning an empty set of block as indicated above
let
runway = uint64(headSlot - startSlot)
# This is the number of blocks that will follow the start block
extraSlots = min(runway div skipStep, requestedCount - 1)
# If `skipStep` is very large, `extraSlots` should be 0 from
# the previous line, so `endSlot` will be equal to `startSlot`:
endSlot = startSlot + extraSlots * skipStep
var
curSlot = endSlot
o = output.len
# Process all blocks that follow the start block (may be zero blocks)
while curSlot > startSlot:
let bs = dag.getBlockIdAtSlot(curSlot)
if bs.isSome and bs.get().isProposed():
o -= 1
output[o] = bs.get().bid
curSlot -= skipStep
# Handle start slot separately (to avoid underflow when computing curSlot)
let bs = dag.getBlockIdAtSlot(startSlot)
if bs.isSome and bs.get().isProposed():
o -= 1
output[o] = bs.get().bid
o # Return the index of the first non-nil item in the output
proc updateState*(
dag: ChainDAGRef, state: var ForkedHashedBeaconState, bsi: BlockSlotId,
save: bool, cache: var StateCache): bool =
## Rewind or advance state such that it matches the given block and slot -
## this may include replaying from an earlier snapshot if blck is on a
## different branch or has advanced to a higher slot number than slot
## If `bs.slot` is higher than `bs.blck.slot`, `updateState` will fill in
## with empty/non-block slots
# First, see if we're already at the requested block. If we are, also check
# that the state has not been advanced past the desired block - if it has,
# an earlier state must be loaded since there's no way to undo the slot
# transitions
let
startTick = Moment.now()
current {.used.} = withState(state):
BlockSlotId.init(forkyState.latest_block_id, forkyState.data.slot)
var
ancestors: seq[BlockId]
found = false
template exactMatch(state: ForkedHashedBeaconState, bsi: BlockSlotId): bool =
# The block is the same and we're at an early enough slot - the state can
# be used to arrive at the desired blockslot
state.matches_block_slot(bsi.bid.root, bsi.slot)
template canAdvance(state: ForkedHashedBeaconState, bsi: BlockSlotId): bool =
# The block is the same and we're at an early enough slot - the state can
# be used to arrive at the desired blockslot
state.can_advance_slots(bsi.bid.root, bsi.slot)
# Fast path: check all caches for an exact match - this is faster than
# advancing a state where there's epoch processing to do, by a wide margin -
# it also avoids `hash_tree_root` for slot processing
if exactMatch(state, bsi):
found = true
elif not save:
# When required to save states, we cannot rely on the caches because that
# would skip the extra processing that save does - not all information that
# goes into the database is cached
if exactMatch(dag.headState, bsi):
assign(state, dag.headState)
found = true
elif exactMatch(dag.clearanceState, bsi):
assign(state, dag.clearanceState)
found = true
elif exactMatch(dag.epochRefState, bsi):
assign(state, dag.epochRefState)
found = true
const RewindBlockThreshold = 64
if not found:
# No exact match found - see if any in-memory state can be used as a base
# onto which we can apply a few blocks - there's a tradeoff here between
# loading the state from disk and performing the block applications
var cur = bsi
while ancestors.len < RewindBlockThreshold:
if isZero(cur.bid.root): # tail reached
break
if canAdvance(state, cur): # Typical case / fast path when there's no reorg
found = true
break
if not save: # see above
if canAdvance(dag.headState, cur):
assign(state, dag.headState)
found = true
break
if canAdvance(dag.clearanceState, cur):
assign(state, dag.clearanceState)
found = true
break
if canAdvance(dag.epochRefState, cur):
assign(state, dag.epochRefState)
found = true
break
if cur.isProposed():
# This is not an empty slot, so the block will need to be applied to
# eventually reach bs
ancestors.add(cur.bid)
# Move slot by slot to capture epoch boundary states
cur = dag.parentOrSlot(cur).valueOr:
break
if not found:
debug "UpdateStateData cache miss",
current = shortLog(current), target = shortLog(bsi)
# Either the state is too new or was created by applying a different block.
# We'll now resort to loading the state from the database then reapplying
# blocks until we reach the desired point in time.
var cur = bsi
ancestors.setLen(0)
# Look for a state in the database and load it - as long as it cannot be
# found, keep track of the blocks that are needed to reach it from the
# state that eventually will be found.
# If we hit the tail, it means that we've reached a point for which we can
# no longer recreate history - this happens for example when starting from
# a checkpoint block
let startEpoch = bsi.slot.epoch
while not canAdvance(state, cur) and
not dag.db.getState(dag.cfg, cur.bid.root, cur.slot, state, noRollback):
# There's no state saved for this particular BlockSlot combination, and
# the state we have can't trivially be advanced (in case it was older than
# RewindBlockThreshold), keep looking..
if cur.isProposed():
# This is not an empty slot, so the block will need to be applied to
# eventually reach bs
ancestors.add(cur.bid)
if cur.slot == GENESIS_SLOT or
(cur.slot.epoch + uint64(EPOCHS_PER_STATE_SNAPSHOT) * 2 < startEpoch):
# We've either walked two full state snapshot lengths or hit the tail
# and still can't find a matching state: this can happen when
# starting the node from an arbitrary finalized checkpoint and not
# backfilling the states
notice "Request for pruned historical state",
request = shortLog(bsi), tail = shortLog(dag.tail),
cur = shortLog(cur)
return false
# Move slot by slot to capture epoch boundary states
cur = dag.parentOrSlot(cur).valueOr:
if not dag.getStateByParent(cur.bid, state):
notice "Request for pruned historical state",
request = shortLog(bsi), tail = shortLog(dag.tail),
cur = shortLog(cur)
return false
break
beacon_state_rewinds.inc()
# Starting state has been assigned, either from memory or database
let
assignTick = Moment.now()
ancestor {.used.} = withState(state):
BlockSlotId.init(forkyState.latest_block_id, forkyState.data.slot)
ancestorRoot {.used.} = getStateRoot(state)
var info: ForkedEpochInfo
# Time to replay all the blocks between then and now
for i in countdown(ancestors.len - 1, 0):
# Because the ancestors are in the database, there's no need to persist them
# again. Also, because we're applying blocks that were loaded from the
# database, we can skip certain checks that have already been performed
# before adding the block to the database.
if (let res = dag.applyBlock(state, ancestors[i], cache, info); res.isErr):
warn "Failed to apply block from database",
blck = shortLog(ancestors[i]),
state_bid = shortLog(state.latest_block_id),
error = res.error()
return false
# ...and make sure to process empty slots as requested
dag.advanceSlots(state, bsi.slot, save, cache, info)
# ...and make sure to load the state cache, if it exists
loadStateCache(dag, cache, bsi.bid, getStateField(state, slot).epoch)
let
assignDur = assignTick - startTick
replayDur = Moment.now() - assignTick
total_state_replay_seconds.inc(replayDur.toFloatSeconds)
# TODO https://github.com/status-im/nim-chronicles/issues/108
if (assignDur + replayDur) >= MinSignificantProcessingDuration:
# This might indicate there's a cache that's not in order or a disk that is
# too slow - for now, it's here for investigative purposes and the cutoff
# time might need tuning
info "State replayed",
blocks = ancestors.len,
slots = getStateField(state, slot) - ancestor.slot,
current = shortLog(current),
ancestor = shortLog(ancestor),
target = shortLog(bsi),
ancestorStateRoot = shortLog(ancestorRoot),
targetStateRoot = shortLog(getStateRoot(state)),
found,
assignDur,
replayDur
elif ancestors.len > 0:
debug "State replayed",
blocks = ancestors.len,
slots = getStateField(state, slot) - ancestor.slot,
current = shortLog(current),
ancestor = shortLog(ancestor),
target = shortLog(bsi),
ancestorStateRoot = shortLog(ancestorRoot),
targetStateRoot = shortLog(getStateRoot(state)),
found,
assignDur,
replayDur
else: # Normal case!
trace "State advanced",
blocks = ancestors.len,
slots = getStateField(state, slot) - ancestor.slot,
current = shortLog(current),
ancestor = shortLog(ancestor),
target = shortLog(bsi),
ancestorStateRoot = shortLog(ancestorRoot),
targetStateRoot = shortLog(getStateRoot(state)),
found,
assignDur,
replayDur
true
proc delState(dag: ChainDAGRef, bsi: BlockSlotId) =
# Delete state and mapping for a particular block+slot
if not dag.isStateCheckpoint(bsi):
return # We only ever save epoch states
if (let root = dag.db.getStateRoot(bsi.bid.root, bsi.slot); root.isSome()):
dag.db.withManyWrites:
dag.db.delStateRoot(bsi.bid.root, bsi.slot)
dag.db.delState(
dag.cfg.consensusForkAtEpoch(bsi.slot.epoch), root.get())
proc pruneBlockSlot(dag: ChainDAGRef, bs: BlockSlot) =
# TODO: should we move that disk I/O to `onSlotEnd`
dag.delState(bs.toBlockSlotId().expect("not nil"))
if bs.isProposed():
# Update light client data
dag.deleteLightClientData(bs.blck.bid)
bs.blck.executionValid = true
dag.forkBlocks.excl(KeyedBlockRef.init(bs.blck))
discard dag.db.delBlock(
dag.cfg.consensusForkAtEpoch(bs.blck.slot.epoch), bs.blck.root)
proc pruneBlocksDAG(dag: ChainDAGRef) =
## This prunes the block DAG
## This does NOT prune the cached state checkpoints and EpochRef
## This must be done after a new finalization point is reached
## to invalidate pending blocks or attestations referring
## to a now invalid fork.
##
## This does NOT update the `dag.lastPrunePoint` field.
## as the caches and fork choice can be pruned at a later time.
# Clean up block refs, walking block by block
let startTick = Moment.now()
# Finalization means that we choose a single chain as the canonical one -
# it also means we're no longer interested in any branches from that chain
# up to the finalization point
let hlen = dag.heads.len
for i in 0..<hlen:
let n = hlen - i - 1
let head = dag.heads[n]
if dag.finalizedHead.blck.isAncestorOf(head):
continue
var cur = head.atSlot()
# The block whose parent is nil is the `BlockRef` that's part of the
# canonical chain but has now been finalized - in theory there could be
# states at empty slot iff the fork had epoch-long gaps where the epoch
# transition was not on the canonical chain - these will not properly get
# cleaned up by the current logic - but they should also be rare
# TODO clean up the above as well
doAssert dag.finalizedHead.blck.parent == nil,
"finalizedHead parent should have been pruned from memory already"
while cur.blck.parent != nil:
dag.pruneBlockSlot(cur)
cur = cur.parentOrSlot
dag.heads.del(n)
debug "Pruned the blockchain DAG",
currentCandidateHeads = dag.heads.len,
prunedHeads = hlen - dag.heads.len,
dagPruneDur = Moment.now() - startTick
# https://github.com/ethereum/consensus-specs/blob/v1.4.0-beta.6/sync/optimistic.md#helpers
template is_optimistic*(dag: ChainDAGRef, bid: BlockId): bool =
let blck =
if bid.slot <= dag.finalizedHead.slot:
dag.finalizedHead.blck
else:
dag.getBlockRef(bid.root).expect("Non-finalized block is known")
not blck.executionValid
proc markBlockVerified*(dag: ChainDAGRef, blck: BlockRef) =
var cur = blck
while true:
cur.executionValid = true
debug "markBlockVerified", blck = shortLog(cur)
if cur.parent.isNil:
break
cur = cur.parent
# Always check at least as far back as the parent so that when a new block
# is added with executionValid already set, it stil sets the ancestors, to
# the next valid in the chain.
if cur.executionValid:
return
iterator syncSubcommittee*(
syncCommittee: openArray[ValidatorIndex],
subcommitteeIdx: SyncSubcommitteeIndex): ValidatorIndex =
var i = subcommitteeIdx.asInt * SYNC_SUBCOMMITTEE_SIZE
let onePastEndIdx = min(syncCommittee.len, i + SYNC_SUBCOMMITTEE_SIZE)
while i < onePastEndIdx:
yield syncCommittee[i]
inc i
iterator syncSubcommitteePairs*(
syncCommittee: openArray[ValidatorIndex],
subcommitteeIdx: SyncSubcommitteeIndex): tuple[validatorIdx: ValidatorIndex,
subcommitteeIdx: int] =
var i = subcommitteeIdx.asInt * SYNC_SUBCOMMITTEE_SIZE
let onePastEndIdx = min(syncCommittee.len, i + SYNC_SUBCOMMITTEE_SIZE)
while i < onePastEndIdx:
yield (syncCommittee[i], i)
inc i
func syncCommitteeParticipants*(dag: ChainDAGRef,
slot: Slot): seq[ValidatorIndex] =
withState(dag.headState):
when consensusFork >= ConsensusFork.Altair:
let
period = sync_committee_period(slot)
curPeriod = sync_committee_period(forkyState.data.slot)
if period == curPeriod:
@(dag.headSyncCommittees.current_sync_committee)
elif period == curPeriod + 1:
@(dag.headSyncCommittees.next_sync_committee)
else: @[]
else:
@[]
func getSubcommitteePositionsAux(
dag: ChainDAGRef,
syncCommittee: openArray[ValidatorIndex],
subcommitteeIdx: SyncSubcommitteeIndex,
validatorIdx: uint64): seq[uint64] =
var pos = 0'u64
for valIdx in syncCommittee.syncSubcommittee(subcommitteeIdx):
if validatorIdx == uint64(valIdx):
result.add pos
inc pos
func getSubcommitteePositions*(
dag: ChainDAGRef,
slot: Slot,
subcommitteeIdx: SyncSubcommitteeIndex,
validatorIdx: uint64): seq[uint64] =
withState(dag.headState):
when consensusFork >= ConsensusFork.Altair:
let
period = sync_committee_period(slot)
curPeriod = sync_committee_period(forkyState.data.slot)
template search(syncCommittee: openArray[ValidatorIndex]): seq[uint64] =
dag.getSubcommitteePositionsAux(
syncCommittee, subcommitteeIdx, validatorIdx)
if period == curPeriod:
search(dag.headSyncCommittees.current_sync_committee)
elif period == curPeriod + 1:
search(dag.headSyncCommittees.next_sync_committee)
else: @[]
else:
@[]
template syncCommitteeParticipants*(
dag: ChainDAGRef,
slot: Slot,
subcommitteeIdx: SyncSubcommitteeIndex): seq[ValidatorIndex] =
toSeq(syncSubcommittee(dag.syncCommitteeParticipants(slot), subcommitteeIdx))
iterator syncCommitteeParticipants*(
dag: ChainDAGRef,
slot: Slot,
subcommitteeIdx: SyncSubcommitteeIndex,
aggregationBits: SyncCommitteeAggregationBits): ValidatorIndex =
for pos, valIdx in dag.syncCommitteeParticipants(slot, subcommitteeIdx):
if pos < aggregationBits.bits and aggregationBits[pos]:
yield valIdx
func needStateCachesAndForkChoicePruning*(dag: ChainDAGRef): bool =
dag.lastPrunePoint != dag.finalizedHead.toBlockSlotId().expect("not nil")
proc pruneStateCachesDAG*(dag: ChainDAGRef) =
## This prunes the cached state checkpoints and EpochRef
## This does NOT prune the state associated with invalidated blocks on a fork
## They are pruned via `pruneBlocksDAG`
##
## This updates the `dag.lastPrunePoint` variable
doAssert dag.needStateCachesAndForkChoicePruning()
let startTick = Moment.now()
block: # Remove states, walking slot by slot
# We remove all state checkpoints that come _before_ the current finalized
# head, as we might frequently be asked to replay states from the
# finalized checkpoint and onwards (for example when validating blocks and
# attestations)
var
finPoint = dag.finalizedHead.toBlockSlotId().expect("not nil")
cur = dag.parentOrSlot(dag.stateCheckpoint(finPoint))
prev = dag.parentOrSlot(dag.stateCheckpoint(dag.lastPrunePoint))
while cur.isSome and prev.isSome and cur.get() != prev.get():
let bs = cur.get()
if not isFinalizedStateSnapshot(bs.slot) and
bs.slot != dag.tail.slot:
dag.delState(bs)
let tmp = cur.get()
cur = dag.parentOrSlot(tmp)
let statePruneTick = Moment.now()
block: # Clean up old EpochRef instances
# After finalization, we can clear up the epoch cache and save memory -
# it will be recomputed if needed
dag.epochRefs.delIt(it.epoch < dag.finalizedHead.slot.epoch)
dag.shufflingRefs.delIt(it.epoch < dag.finalizedHead.slot.epoch)
let epochRefPruneTick = Moment.now()
dag.lastPrunePoint = dag.finalizedHead.toBlockSlotId().expect("not nil")
debug "Pruned the state checkpoints and DAG caches.",
statePruneDur = statePruneTick - startTick,
epochRefPruneDur = epochRefPruneTick - statePruneTick
func pruneStep(horizon, lastHorizon, lastBlockHorizon: Slot):
tuple[stateHorizon, blockHorizon: Slot] =
## Compute a reasonable incremental pruning step considering the current
## horizon, how far the database has been pruned already and where we want the
## tail to be - the return value shows the first state and block that we
## should _keep_ (inclusive).
const SLOTS_PER_STATE_SNAPSHOT =
uint64(EPOCHS_PER_STATE_SNAPSHOT * SLOTS_PER_EPOCH)
let
blockHorizon = block:
let
# Keep up with horizon if it's moving fast, ie if we're syncing
maxSlots = max(horizon - lastHorizon, MAX_SLOTS_PER_PRUNE)
# Move the block horizon cap with a lag so that it moves slot-by-slot
# instead of a big jump every time we prune a state - assuming we
# prune every slot, this makes us prune one slot at a time instead of
# a burst of prunes (as computed by maxSlots) around every snapshot
# change followed by no pruning for the rest of the period
maxBlockHorizon =
if horizon + 1 >= SLOTS_PER_STATE_SNAPSHOT:
horizon + 1 - SLOTS_PER_STATE_SNAPSHOT
else:
Slot(0)
# `lastBlockHorizon` captures the case where we're incrementally
# pruning a database that hasn't been pruned for a while: it's
# initialized to a pre-tail value on startup and moves to approach
# `maxBlockHorizon`.
min(maxBlockHorizon, lastBlockHorizon + maxSlots)
# Round up such that we remove state only once blocks have been removed
stateHorizon =
((blockHorizon + SLOTS_PER_STATE_SNAPSHOT - 1) div
SLOTS_PER_STATE_SNAPSHOT) * SLOTS_PER_STATE_SNAPSHOT
(Slot(stateHorizon), blockHorizon)
proc pruneHistory*(dag: ChainDAGRef, startup = false) =
## Perform an incremental pruning step of the history
if dag.db.db.readOnly:
return
let
horizon = dag.horizon()
(stateHorizon, blockHorizon) = pruneStep(
horizon, dag.lastHistoryPruneHorizon, dag.lastHistoryPruneBlockHorizon)
doAssert blockHorizon <= stateHorizon,
"we must never prune blocks while leaving the state"
debug "Pruning history",
horizon, blockHorizon, stateHorizon,
lastHorizon = dag.lastHistoryPruneHorizon,
lastBlockHorizon = dag.lastHistoryPruneBlockHorizon,
tail = dag.tail, head = dag.head
dag.lastHistoryPruneHorizon = horizon
dag.lastHistoryPruneBlockHorizon = blockHorizon
dag.db.withManyWrites:
if stateHorizon > dag.tail.slot:
# First, we want to see if it's possible to prune any states - we store one
# state every EPOCHS_PER_STATE_SNAPSHOT, so this happens infrequently.
var
cur = dag.getBlockIdAtSlot(stateHorizon)
var first = true
while cur.isSome():
let bs = cur.get()
# We don't delete legacy states because the legacy database is openend
# in read-only and slow to delete from due to its sub-optimal structure
if dag.db.containsState(
dag.cfg, bs.bid.root, bs.slot..bs.slot, legacy = first):
if first:
# We leave the state on the prune horizon intact and update the tail
# to point to this state, indicating the new point in time from
# which we can load states in general.
debug "Updating tail", bs
dag.db.putTailBlock(bs.bid.root)
dag.tail = bs.bid
first = false
else:
debug "Pruning historical state", bs
dag.delState(bs)
elif not bs.isProposed:
trace "Reached already-pruned slot, done pruning states", bs
break
if bs.isProposed:
# We store states either at the same slot at the block (checkpoint) or
# by advancing the slot to the nearest epoch start - check both when
# pruning
cur = dag.parentOrSlot(bs)
elif bs.slot.epoch > EPOCHS_PER_STATE_SNAPSHOT:
# Jump one snapshot interval at a time, but don't prune genesis
cur = dag.getBlockIdAtSlot(start_slot(bs.slot.epoch() - EPOCHS_PER_STATE_SNAPSHOT))
else:
break
# Prune blocks after sanity-checking that we don't prune post-tail blocks -
# this could happen if a state is missing at the expected state horizon and
# would indicate a partially inconsistent database since the base
# invariant is that there exists a state at the snapshot slot - better not
# further mess things up regardless
if blockHorizon > GENESIS_SLOT and blockHorizon <= dag.tail.slot:
var
# Leave the horizon block itself
cur = dag.getBlockIdAtSlot(blockHorizon - 1).map(proc(x: auto): auto = x.bid)
while cur.isSome:
let
bid = cur.get()
fork = dag.cfg.consensusForkAtEpoch(bid.slot.epoch)
if bid.slot == GENESIS_SLOT:
# Leave genesis block for nostalgia and the REST API
break
if not dag.db.delBlock(fork, bid.root):
# Stop at the first gap - this is typically the pruning point of the
# previous call to pruneHistory. An inconsistent DB might have more
# blocks beyond that point but we have no efficient way of detecting
# that.
break
cur = dag.parent(bid)
# TODO There have been varied reports of startup pruning causing long
# startup times - an incremental approach would be needed here also
if false and
startup and
dag.cfg.consensusForkAtEpoch(blockHorizon.epoch) > ConsensusFork.Phase0:
# Once during start, we'll clear all "old fork" data - this ensures we get
# rid of any leftover junk in the tables - we do so after linear pruning
# so as to "mostly" clean up the phase0 tables as well (which cannot be
# pruned easily by fork) - one fork at a time, so as not to take too long
let stateFork = dag.cfg.consensusForkAtEpoch(dag.tail.slot.epoch)
var clearedStates = false
if stateFork > ConsensusFork.Phase0:
for fork in ConsensusFork.Phase0..<stateFork:
if dag.db.clearStates(fork):
clearedStates = true
break
let blockFork = dag.cfg.consensusForkAtEpoch(blockHorizon.epoch)
if not clearedStates and blockFork > ConsensusFork.Phase0:
for fork in ConsensusFork.Phase0..<blockFork:
if dag.db.clearBlocks(fork):
break
proc loadExecutionBlockHash*(
dag: ChainDAGRef, bid: BlockId): Opt[Eth2Digest] =
let blockData = dag.getForkedBlock(bid).valueOr:
# Besides database inconsistency issues, this is hit with checkpoint sync.
# The initial `BlockRef` is creted before the checkpoint block is loaded.
# It is backfilled later, so return `none` and keep retrying.
return Opt.none(Eth2Digest)
withBlck(blockData):
when consensusFork >= ConsensusFork.Bellatrix:
Opt.some forkyBlck.message.body.execution_payload.block_hash
else:
Opt.some ZERO_HASH
proc loadExecutionBlockHash*(
dag: ChainDAGRef, blck: BlockRef): Opt[Eth2Digest] =
if blck.executionBlockHash.isNone:
blck.executionBlockHash = dag.loadExecutionBlockHash(blck.bid)
blck.executionBlockHash
from std/packedsets import PackedSet, incl, items
func getValidatorChangeStatuses(
state: ForkedHashedBeaconState, vis: openArray[ValidatorIndex]):
PackedSet[ValidatorIndex] =
var res: PackedSet[ValidatorIndex]
withState(state):
for vi in vis:
if forkyState.data.validators[vi].withdrawal_credentials.data[0] ==
BLS_WITHDRAWAL_PREFIX:
res.incl vi
res
func checkBlsToExecutionChanges(
state: ForkedHashedBeaconState, vis: PackedSet[ValidatorIndex]): bool =
# Within each fork, BLS_WITHDRAWAL_PREFIX to ETH1_ADDRESS_WITHDRAWAL_PREFIX
# and never ETH1_ADDRESS_WITHDRAWAL_PREFIX to BLS_WITHDRAWAL_PREFIX. Latter
# can still happen via reorgs.
# Cases:
# 1) unchanged (BLS_WITHDRAWAL_PREFIX or ETH1_ADDRESS_WITHDRAWAL_PREFIX) from
# old to new head.
# 2) ETH1_ADDRESS_WITHDRAWAL_PREFIX to BLS_WITHDRAWAL_PREFIX
# 3) BLS_WITHDRAWAL_PREFIX to ETH1_ADDRESS_WITHDRAWAL_PREFIX
#
# Only report (3), i.e. whether there were validator indices with withdrawal
# credentials previously using BLS_WITHDRAWAL_PREFIX now using, instead, the
# ETH1_ADDRESS_WITHDRAWAL_PREFIX prefix indicating a BLS to execution change
# went through.
#
# Since it tracks head, it's possible reorgs trigger reporting the same
# validator indices multiple times; this is fine.
withState(state):
anyIt( vis, forkyState.data.validators[it].has_eth1_withdrawal_credential)
proc updateHead*(
dag: ChainDAGRef, newHead: BlockRef, quarantine: var Quarantine,
knownValidators: openArray[ValidatorIndex]) =
## Update what we consider to be the current head, as given by the fork
## choice.
##
## The choice of head affects the choice of finalization point - the order
## of operations naturally becomes important here - after updating the head,
## blocks that were once considered potential candidates for a tree will
## now fall from grace, or no longer be considered resolved.
doAssert not newHead.isNil()
# Could happen if enough blocks get invalidated and would corrupt database -
# When finalized checkpoint is empty, the slot may also be smaller
doAssert newHead.slot >= dag.finalizedHead.slot or
newHead == dag.finalizedHead.blck
let lastHead = dag.head
logScope:
newHead = shortLog(newHead)
lastHead = shortLog(lastHead)
if lastHead == newHead:
trace "No head block update"
return
if newHead.parent.isNil:
# The new head should always have the finalizedHead as ancestor - thus,
# this should not happen except in a race condition where the selected
# `BlockRef` had its parent set to nil as happens during finalization -
# notably, resetting the head to be the finalizedHead is not allowed
error "Cannot update head to block without parent"
return
let
lastHeadStateRoot = getStateRoot(dag.headState)
lastHeadMergeComplete = dag.headState.is_merge_transition_complete()
lastHeadKind = dag.headState.kind
lastKnownValidatorsChangeStatuses = getValidatorChangeStatuses(
dag.headState, knownValidators)
# Start off by making sure we have the right state - updateState will try
# to use existing in-memory states to make this smooth
var cache: StateCache
if not updateState(
dag, dag.headState, newHead.bid.atSlot(), false, cache):
# Advancing the head state should never fail, given that the tail is
# implicitly finalised, the head is an ancestor of the tail and we always
# store the tail state in the database, as well as every epoch slot state in
# between
fatal "Unable to load head state during head update, database corrupt?",
lastHead = shortLog(lastHead)
quit 1
dag.head = newHead
if dag.headState.is_merge_transition_complete() and not
lastHeadMergeComplete and
dag.vanityLogs.onMergeTransitionBlock != nil:
dag.vanityLogs.onMergeTransitionBlock()
if dag.headState.kind > lastHeadKind:
case dag.headState.kind
of ConsensusFork.Phase0 .. ConsensusFork.Bellatrix:
discard
of ConsensusFork.Capella:
if dag.vanityLogs.onUpgradeToCapella != nil:
dag.vanityLogs.onUpgradeToCapella()
of ConsensusFork.Deneb:
if dag.vanityLogs.onUpgradeToDeneb != nil:
dag.vanityLogs.onUpgradeToDeneb()
if dag.vanityLogs.onKnownBlsToExecutionChange != nil and
checkBlsToExecutionChanges(
dag.headState, lastKnownValidatorsChangeStatuses):
dag.vanityLogs.onKnownBlsToExecutionChange()
dag.db.putHeadBlock(newHead.root)
updateBeaconMetrics(dag.headState, dag.head.bid, cache)
withState(dag.headState):
when consensusFork >= ConsensusFork.Altair:
dag.headSyncCommittees = forkyState.data.get_sync_committee_cache(cache)
let
finalized_checkpoint =
getStateField(dag.headState, finalized_checkpoint)
finalizedSlot =
# finalized checkpoint may move back in the head state compared to what
# we've seen in other forks - it does not move back in fork choice
# however, so we'll use the last-known-finalized in that case
max(finalized_checkpoint.epoch.start_slot(), dag.finalizedHead.slot)
finalizedHead = newHead.atSlot(finalizedSlot)
doAssert (not finalizedHead.blck.isNil),
"Block graph should always lead to a finalized block"
# Update light client data
dag.processHeadChangeForLightClient()
let (isAncestor, ancestorDepth) = lastHead.getDepth(newHead)
if not(isAncestor):
notice "Updated head block with chain reorg",
headParent = shortLog(newHead.parent),
stateRoot = shortLog(getStateRoot(dag.headState)),
justified = shortLog(getStateField(
dag.headState, current_justified_checkpoint)),
finalized = shortLog(getStateField(dag.headState, finalized_checkpoint)),
isOptHead = not newHead.executionValid
if not(isNil(dag.onReorgHappened)):
let
# TODO (cheatfate): Proper implementation required
data = ReorgInfoObject.init(dag.head.slot, uint64(ancestorDepth),
lastHead.root, newHead.root,
lastHeadStateRoot,
getStateRoot(dag.headState))
dag.onReorgHappened(data)
# A reasonable criterion for "reorganizations of the chain"
quarantine.clearAfterReorg()
beacon_reorgs_total_total.inc()
beacon_reorgs_total.inc()
else:
debug "Updated head block",
stateRoot = shortLog(getStateRoot(dag.headState)),
justified = shortLog(getStateField(
dag.headState, current_justified_checkpoint)),
finalized = shortLog(getStateField(dag.headState, finalized_checkpoint)),
isOptHead = not newHead.executionValid
if not(isNil(dag.onHeadChanged)):
let
depRoot = withState(dag.headState): forkyState.proposer_dependent_root
prevDepRoot = withState(dag.headState):
forkyState.attester_dependent_root
epochTransition = (finalizedHead != dag.finalizedHead)
# TODO (cheatfate): Proper implementation required
data = HeadChangeInfoObject.init(dag.head.slot, dag.head.root,
getStateRoot(dag.headState),
epochTransition, prevDepRoot,
depRoot)
dag.onHeadChanged(data)
withState(dag.headState):
# Every time the head changes, the "canonical" view of balances and other
# state-related metrics change - notify the validator monitor.
# Doing this update during head update ensures there's a reasonable number
# of such updates happening - at most once per valid block.
dag.validatorMonitor[].registerState(forkyState.data)
if finalizedHead != dag.finalizedHead:
debug "Reached new finalization checkpoint",
stateRoot = shortLog(getStateRoot(dag.headState)),
justified = shortLog(getStateField(
dag.headState, current_justified_checkpoint)),
finalized = shortLog(getStateField(dag.headState, finalized_checkpoint))
let oldFinalizedHead = dag.finalizedHead
block:
# Update `dag.finalizedBlocks` with all newly finalized blocks (those
# newer than the previous finalized head), then update `dag.finalizedHead`
var newFinalized: seq[BlockId]
var tmp = finalizedHead.blck
while not isNil(tmp) and tmp.slot >= dag.finalizedHead.slot:
newFinalized.add(tmp.bid)
if tmp != finalizedHead.blck:
# The newly finalized block itself should remain in here so that fork
# choice still can find it via root
dag.forkBlocks.excl(KeyedBlockRef.init(tmp))
let p = tmp.parent
tmp.parent = nil # Reset all parent links to release memory
tmp = p
dag.finalizedHead = finalizedHead
dag.db.updateFinalizedBlocks(newFinalized)
let oldBlockHash = dag.loadExecutionBlockHash(oldFinalizedHead.blck)
if oldBlockHash.isSome and oldBlockHash.unsafeGet.isZero:
let newBlockHash = dag.loadExecutionBlockHash(dag.finalizedHead.blck)
if newBlockHash.isSome and not newBlockHash.unsafeGet.isZero:
if dag.vanityLogs.onFinalizedMergeTransitionBlock != nil:
dag.vanityLogs.onFinalizedMergeTransitionBlock()
# Pruning the block dag is required every time the finalized head changes
# in order to clear out blocks that are no longer viable and should
# therefore no longer be considered as part of the chain we're following
dag.pruneBlocksDAG()
# Update light client data
dag.processFinalizationForLightClient(oldFinalizedHead)
# Send notification about new finalization point via callback.
if not(isNil(dag.onFinHappened)):
let stateRoot =
if dag.finalizedHead.slot == dag.head.slot: getStateRoot(dag.headState)
elif dag.finalizedHead.slot + SLOTS_PER_HISTORICAL_ROOT > dag.head.slot:
getStateField(dag.headState, state_roots).data[
int(dag.finalizedHead.slot mod SLOTS_PER_HISTORICAL_ROOT)]
else:
Eth2Digest() # The thing that finalized was >8192 blocks old?
# TODO (cheatfate): Proper implementation required
let data = FinalizationInfoObject.init(
dag.finalizedHead.blck.root, stateRoot, dag.finalizedHead.slot.epoch)
dag.onFinHappened(dag, data)
proc isInitialized*(T: type ChainDAGRef, db: BeaconChainDB): Result[void, cstring] =
## Lightweight check to see if it is likely that the given database has been
## initialized
let
tailBlockRoot = db.getTailBlock()
if not tailBlockRoot.isSome():
return err("Tail block root missing")
let
tailBlock = db.getBlockId(tailBlockRoot.get())
if not tailBlock.isSome():
return err("Tail block information missing")
ok()
proc preInit*(
T: type ChainDAGRef, db: BeaconChainDB, state: ForkedHashedBeaconState) =
## Initialize a database using the given state, which potentially may be a
## non-genesis state.
##
## When used with a non-genesis state, the resulting database will not be
## compatible with pre-22.11 versions.
logScope:
stateRoot = $getStateRoot(state)
stateSlot = getStateField(state, slot)
doAssert getStateField(state, slot).is_epoch,
"Can only initialize database from epoch states"
withState(state):
db.putState(forkyState)
if forkyState.data.slot == GENESIS_SLOT:
let blck = get_initial_beacon_block(forkyState)
db.putBlock(blck)
db.putGenesisBlock(blck.root)
db.putHeadBlock(blck.root)
db.putTailBlock(blck.root)
notice "Database initialized from genesis",
blockRoot = $blck.root
else:
let blockRoot = forkyState.latest_block_root()
# We write a summary but not the block contents - these will have to be
# backfilled from the network
db.putBeaconBlockSummary(blockRoot, BeaconBlockSummary(
slot: forkyState.data.latest_block_header.slot,
parent_root: forkyState.data.latest_block_header.parent_root
))
db.putHeadBlock(blockRoot)
db.putTailBlock(blockRoot)
if db.getGenesisBlock().isSome():
notice "Checkpoint written to database", blockRoot = $blockRoot
else:
notice "Database initialized from checkpoint", blockRoot = $blockRoot
proc getProposer*(
dag: ChainDAGRef, head: BlockRef, slot: Slot): Opt[ValidatorIndex] =
let
epochRef = dag.getEpochRef(head.bid, slot.epoch(), false).valueOr:
notice "Cannot load EpochRef for given head", head, slot, error
return Opt.none(ValidatorIndex)
slotInEpoch = slot.since_epoch_start()
let proposer = epochRef.beacon_proposers[slotInEpoch]
if proposer.isSome():
if proposer.get().uint64 >= dag.db.immutableValidators.lenu64():
# Sanity check - it should never happen that the key cache doesn't contain
# a key for the selected proposer - that would mean that we somehow
# created validators in the state without updating the cache!
warn "Proposer key not found",
keys = dag.db.immutableValidators.lenu64(), proposer = proposer.get()
return Opt.none(ValidatorIndex)
proposer
proc getProposalState*(
dag: ChainDAGRef, head: BlockRef, slot: Slot, cache: var StateCache):
Result[ref ForkedHashedBeaconState, cstring] =
## Return a state suitable for making proposals for the given head and slot -
## in particular, the state can be discarded after use and does not have a
## state root set
# Start with the clearance state, since this one typically has been advanced
# and thus has a hot hash tree cache
let state = assignClone(dag.clearanceState)
var
info = ForkedEpochInfo()
if not state[].can_advance_slots(head.root, slot):
# The last state root will be computed as part of block production, so skip
# it now
if not dag.updateState(
state[], head.atSlot(slot - 1).toBlockSlotId().expect("not nil"),
false, cache):
error "Cannot get proposal state - skipping block production, database corrupt?",
head = shortLog(head),
slot
return err("Cannot create proposal state")
else:
loadStateCache(dag, cache, head.bid, slot.epoch)
if getStateField(state[], slot) < slot:
process_slots(
dag.cfg, state[], slot, cache, info,
{skipLastStateRootCalculation}).expect("advancing 1 slot should not fail")
ok state
func aggregateAll*(
dag: ChainDAGRef,
validator_indices: openArray[ValidatorIndex]): Result[CookedPubKey, cstring] =
if validator_indices.len == 0:
# Aggregation spec requires non-empty collection
# - https://tools.ietf.org/html/draft-irtf-cfrg-bls-signature-04
# Consensus specs require at least one attesting index in attestation
# - https://github.com/ethereum/consensus-specs/blob/v1.4.0-beta.6/specs/phase0/beacon-chain.md#is_valid_indexed_attestation
return err("aggregate: no attesting keys")
let
firstKey = dag.validatorKey(validator_indices[0]).valueOr:
return err("aggregate: invalid validator index")
var aggregateKey{.noinit.}: AggregatePublicKey
aggregateKey.init(firstKey)
for i in 1 ..< validator_indices.len:
let key = dag.validatorKey(validator_indices[i]).valueOr:
return err("aggregate: invalid validator index")
aggregateKey.aggregate(key)
ok(finish(aggregateKey))
func aggregateAll*(
dag: ChainDAGRef,
validator_indices: openArray[ValidatorIndex|uint64],
bits: BitSeq | BitArray): Result[CookedPubKey, cstring] =
if validator_indices.len() != bits.len():
return err("aggregateAll: mismatch in bits length")
var
aggregateKey{.noinit.}: AggregatePublicKey
inited = false
for i in 0..<bits.len():
if bits[i]:
let key = dag.validatorKey(validator_indices[i]).valueOr:
return err("aggregate: invalid validator index")
if inited:
aggregateKey.aggregate(key)
else:
aggregateKey = AggregatePublicKey.init(key)
inited = true
if not inited:
err("aggregate: no attesting keys")
else:
ok(finish(aggregateKey))
func needsBackfill*(dag: ChainDAGRef): bool =
dag.backfill.slot > dag.horizon
proc rebuildIndex*(dag: ChainDAGRef) =
## After a checkpoint sync, we lack intermediate states to replay from - this
## function rebuilds them so that historical replay can take place again
## TODO the pruning of junk states could be moved to a separate function that
## runs either on startup
# First, we check what states we already have in the database - that allows
# resuming the operation at any time
let
roots = dag.db.loadStateRoots()
historicalRoots = getStateField(dag.headState, historical_roots).asSeq()
historicalSummaries = dag.headState.historical_summaries.asSeq()
var
canonical = newSeq[Eth2Digest](
(dag.finalizedHead.slot.epoch + EPOCHS_PER_STATE_SNAPSHOT - 1) div
EPOCHS_PER_STATE_SNAPSHOT)
# `junk` puts in place some infrastructure to prune unnecessary states - it
# will be more useful in the future as a base for pruning
junk: seq[((Slot, Eth2Digest), Eth2Digest)]
for k, v in roots:
if k[0] >= dag.finalizedHead.slot:
continue # skip newer stuff
if k[0] < dag.backfill.slot:
continue # skip stuff for which we have no blocks
if not isFinalizedStateSnapshot(k[0]):
# `tail` will move at the end of the process, so we won't need any
# intermediate states
junk.add((k, v))
continue # skip non-snapshot slots
if k[0] > 0:
let bs = dag.getBlockIdAtSlot(k[0] - 1)
if bs.isNone or bs.get().bid.root != k[1]:
# remove things that are no longer a canonical part of the chain or
# cannot be reached via a block
junk.add((k, v))
continue
if not dag.db.containsState(dag.cfg.consensusForkAtEpoch(k[0].epoch), v):
continue # If it's not in the database..
canonical[k[0].epoch div EPOCHS_PER_STATE_SNAPSHOT] = v
let
state = (ref ForkedHashedBeaconState)()
var
cache: StateCache
info: ForkedEpochInfo
tailBid: Opt[BlockId]
states: int
# `canonical` holds all slots at which a state is expected to appear, using a
# zero root whenever a particular state is missing - this way, if there's
# partial progress or gaps, they will be dealt with correctly
for i, state_root in canonical.mpairs():
let
slot = Epoch(i * EPOCHS_PER_STATE_SNAPSHOT).start_slot
if slot < dag.backfill.slot:
# TODO if we have era files, we could try to load blocks from them at
# this point
# TODO if we don't do the above, we can of course compute the starting `i`
continue
if tailBid.isNone():
if state_root.isZero:
# If we can find an era file with this state, use it as an alternative
# starting point - ignore failures for now
if dag.era.getState(
historicalRoots, historicalSummaries, slot, state[]).isOk():
state_root = getStateRoot(state[])
withState(state[]): dag.db.putState(forkyState)
tailBid = Opt.some state[].latest_block_id()
else:
if not dag.db.getState(
dag.cfg.consensusForkAtEpoch(slot.epoch), state_root, state[],
noRollback):
fatal "Cannot load state, database corrupt or created for a different network?",
state_root, slot
quit 1
tailBid = Opt.some state[].latest_block_id()
continue
if i == 0 or canonical[i - 1].isZero:
reset(tailBid) # No unbroken history!
continue
if not state_root.isZero:
states += 1
continue
let
startSlot = Epoch((i - 1) * EPOCHS_PER_STATE_SNAPSHOT).start_slot
info "Recreating state snapshot",
slot, startStateRoot = canonical[i - 1], startSlot
if getStateRoot(state[]) != canonical[i - 1]:
if not dag.db.getState(
dag.cfg.consensusForkAtEpoch(startSlot.epoch), canonical[i - 1],
state[], noRollback):
error "Can't load start state, database corrupt?",
startStateRoot = shortLog(canonical[i - 1]), slot = startSlot
return
for slot in startSlot..<startSlot + (EPOCHS_PER_STATE_SNAPSHOT * SLOTS_PER_EPOCH):
let bids = dag.getBlockIdAtSlot(slot).valueOr:
warn "Block id missing, cannot continue - database corrupt?", slot
return
# The slot check is needed to avoid re-applying a block
if bids.isProposed and getStateField(state[], latest_block_header).slot < bids.bid.slot:
let res = dag.applyBlock(state[], bids.bid, cache, info)
if res.isErr:
error "Failed to apply block while building index",
state_bid = shortLog(state[].latest_block_id()),
error = res.error()
return
if slot.is_epoch:
cache.prune(slot.epoch)
process_slots(
dag.cfg, state[], slot, cache, info,
dag.updateFlags).expect("process_slots shouldn't fail when state slot is correct")
withState(state[]):
dag.db.putState(forkyState)
dag.db.checkpoint()
state_root = forkyState.root
# Now that we've found a starting point and topped up with "intermediate"
# states, we can update the tail to start at the starting point of the
# first loadable state
if tailBid.isSome():
dag.tail = tailBid.get()
dag.db.putTailBlock(dag.tail.root)
if junk.len > 0:
info "Dropping redundant states", states, redundant = junk.len
for i in junk:
dag.db.delStateRoot(i[0][1], i[0][0])
dag.db.delState(dag.cfg.consensusForkAtEpoch(i[0][0].epoch), i[1])