status-im
/
eth2.0-specs
mirror of https://github.com/status-im/eth2.0-specs.git
2
0
Fork 0
Code Issues Projects Releases Wiki Activity

update pending header weights after epoch transition, fix committee index loop, fix header processing status assert, add todos for Altair-like shard attestation rewards

This commit is contained in:
protolambda 2021-05-31 18:55:08 +02:00
parent 5a235d0251
commit 2545c3e2d0
No known key found for this signature in database
GPG Key ID: EC89FDBB2B4C7623
1 changed files with 42 additions and 32 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

74
specs/sharding/beacon-chain.md
View File

@ -251,6 +251,8 @@ class PendingShardHeader(Container):
votes: Bitlist[MAX_VALIDATORS_PER_COMMITTEE] votes: Bitlist[MAX_VALIDATORS_PER_COMMITTEE]
# Sum of effective balances of votes # Sum of effective balances of votes
weight: Gwei weight: Gwei
# When the header was last updated, as reference for weight accuracy
update_slot: Slot
``` ```
### `ShardBlobReference` ### `ShardBlobReference`
@ -538,32 +540,39 @@ def update_pending_shard_work(state: BeaconState, attestation: Attestation) -> N
buffer_index = attestation.data.slot % SHARD_STATE_MEMORY_SLOTS buffer_index = attestation.data.slot % SHARD_STATE_MEMORY_SLOTS
committee_work = state.shard_buffer[buffer_index][attestation_shard] committee_work = state.shard_buffer[buffer_index][attestation_shard]
# Skip attestation vote accounting if the header is already confirmed # Skip attestation vote accounting if the header is not pending
if committee_work.status.selector == CONFIRMED_SHARD_DATA: if committee_work.status.selector != PENDING_SHARD_DATA:
# TODO In Altair: set participation bit flag, if attestation matches winning header.
return return
# Note that shard-slot combinations without an assigned committee do not have a pending state
assert shard_info.status.selector == PENDING_SHARD_DATA
current_headers: Sequence[PendingShardHeader] = committee_work.status.value current_headers: Sequence[PendingShardHeader] = committee_work.status.value
# Find the corresponding header, abort if it cannot be found # Find the corresponding header, abort if it cannot be found
header_index = [header.root for header in current_headers].index(attestation.data.shard_header_root) header_index = [header.root for header in current_headers].index(attestation.data.shard_header_root)
# Update votes bitfield in the state
pending_header: PendingShardHeader = current_headers[header_index] pending_header: PendingShardHeader = current_headers[header_index]
full_committee = get_beacon_committee(state, attestation.data.slot, attestation.data.index) full_committee = get_beacon_committee(state, attestation.data.slot, attestation.data.index)
participants_balance = Gwei(0) full_committee_balance = Gwei(0)
# The weight may be outdated if it is not the initial weight, and from a previous epoch
if pending_header.weight != 0 and compute_epoch_at_slot(pending_header.update_slot) < get_current_epoch(state):
pending_header.weight = sum(state.validators[index].effective_balance for index, bit
in zip(full_committee, pending_header.votes) if bit)
pending_header.update_slot = state.slot
# Update votes bitfield in the state, update weights
for i, bit in enumerate(attestation.aggregation_bits): for i, bit in enumerate(attestation.aggregation_bits):
weight = state.validators[full_committee[i]].effective_balance weight = state.validators[full_committee[i]].effective_balance
full_committee_balance += weight
if bit: if bit:
if not pending_header.votes[i]: if not pending_header.votes[i]:
pending_header.weight += weight pending_header.weight += weight
pending_header.votes[i] = True pending_header.votes[i] = True
participants_balance += weight
# Check if the PendingShardHeader is eligible for expedited confirmation, requiring 2/3 of balance attesting # Check if the PendingShardHeader is eligible for expedited confirmation, requiring 2/3 of balance attesting
full_committee_balance = get_total_balance(state, set(full_committee)) if pending_header.weight * 3 >= full_committee_balance * 2:
if participants_balance * 3 >= full_committee_balance * 2: # TODO In Altair: set participation bit flag for voters of this early winning header
if pending_header.commitment == DataCommitment(): if pending_header.commitment == DataCommitment():
# The committee voted to not confirm anything # The committee voted to not confirm anything
state.shard_buffer[buffer_index][attestation_shard].change( state.shard_buffer[buffer_index][attestation_shard].change(
@ -625,6 +634,7 @@ def process_shard_header(state: BeaconState, signed_header: SignedShardBlobHeade
root=header_root, root=header_root,
votes=initial_votes, votes=initial_votes,
weight=0, weight=0,
update_slot=state.slot,
) )
# Include it in the pending list # Include it in the pending list
@ -669,19 +679,18 @@ This epoch transition overrides the Merge epoch transition:
```python ```python
def process_epoch(state: BeaconState) -> None: def process_epoch(state: BeaconState) -> None:
process_justification_and_finalization(state)
process_rewards_and_penalties(state)
process_registry_updates(state)
process_slashings(state)
# Sharding # Sharding
process_pending_shard_confirmations(state) process_pending_shard_confirmations(state)
charge_confirmed_shard_fees(state) charge_confirmed_shard_fees(state)
reset_pending_shard_work(state) reset_pending_shard_work(state)
# Phase0
process_justification_and_finalization(state)
process_rewards_and_penalties(state)
process_registry_updates(state)
process_slashings(state)
# Final updates # Final updates
# Phase 0
process_eth1_data_reset(state) process_eth1_data_reset(state)
process_effective_balance_updates(state) process_effective_balance_updates(state)
process_slashings_reset(state) process_slashings_reset(state)
@ -711,6 +720,7 @@ def process_pending_shard_confirmations(state: BeaconState) -> None:
committee_work = state.shard_buffer[buffer_index][shard_index] committee_work = state.shard_buffer[buffer_index][shard_index]
if committee_work.selector == PENDING_SHARD_DATA: if committee_work.selector == PENDING_SHARD_DATA:
winning_header = max(committee_work.value, key=lambda header: header.weight) winning_header = max(committee_work.value, key=lambda header: header.weight)
# TODO In Altair: set participation bit flag of voters for winning header
if winning_header.commitment == DataCommitment(): if winning_header.commitment == DataCommitment():
committee_work.change(selector=UNCONFIRMED_SHARD_DATA, value=None) committee_work.change(selector=UNCONFIRMED_SHARD_DATA, value=None)
else: else:
@ -768,23 +778,23 @@ def reset_pending_shard_work(state: BeaconState) -> None:
state.shard_buffer[buffer_index] = [ShardWork() for _ in range(active_shards)] state.shard_buffer[buffer_index] = [ShardWork() for _ in range(active_shards)]
start_shard = get_start_shard(state, slot) start_shard = get_start_shard(state, slot)
for shard_index in range(state.shard_buffer[buffer_index]): for committee_index in range(committees_per_slot):
if start_shard <= shard_index < start_shard + committees_per_slot: shard = (start_shard + committee_index) % active_shards
# a committee is available, initialize a pending shard-header list # a committee is available, initialize a pending shard-header list
committee_index = CommitteeIndex(shard_index - start_shard) committee_length = len(get_beacon_committee(state, slot, committee_index))
committee_length = len(get_beacon_committee(state, slot, committee_index)) state.shard_buffer[buffer_index][shard].change(
state.shard_buffer[buffer_index][shard_index].change( selector=PENDING_SHARD_DATA,
selector=PENDING_SHARD_DATA, value=List[PendingShardHeader, MAX_SHARD_HEADERS_PER_SHARD](
value=List[PendingShardHeader, MAX_SHARD_HEADERS_PER_SHARD]( PendingShardHeader(
PendingShardHeader( commitment=DataCommitment(),
commitment=DataCommitment(), root=Root(),
root=Root(), votes=Bitlist[MAX_VALIDATORS_PER_COMMITTEE]([0] * committee_length),
votes=Bitlist[MAX_VALIDATORS_PER_COMMITTEE]([0] * committee_length), weight=0,
weight=0, update_slot=slot,
)
) )
) )
# the shard is inactive for this slot otherwise, no committee available, default to UNCONFIRMED_SHARD_DATA. )
# a shard without committee available defaults to UNCONFIRMED_SHARD_DATA.
``` ```
#### `process_shard_epoch_increment` #### `process_shard_epoch_increment`