* fix replays stalling processing
Occasionally, attestations will arrive that vote for a target derived
either from the finalized block or earlier. In these cases, Nimbus would
replay the state transition of up to 32 epochs worth of blocks because
the finalized state has been pruned, delaying other processing and
leading to poor inclusion distance.
* put cheap attestation checks before forming EpochRef
* check that attestation target is not from an unviable history with
regards to finalization
* fix overly aggressive state pruning removing the state close to the
finalized checkpoint resulting in rare long replays for valid
attestations
* log long replays
* harden logging and traversal of nil BlockSlot
* simplify target check
no need to lookup target in chain dag again
* fixup
* fixup
* use IntSet rather than HashSet[ValidatorIndex]
* add bounds check before uint64 -> int conversion
* use intsets in block transitions
* remove superfluous Nim issue explanation/reference
* performance fixes
* don't mark tree cache as dirty on read-only List accesses
* store only blob in memory for keys and signatures, parse blob lazily
* compare public keys by blob instead of parsing / converting to raw
* compare Eth2Digest using non-constant-time comparison
* avoid some unnecessary validator copying
This branch will in particular speed up deposit processing which has
been slowing down block replay.
Pre (mainnet, 1600 blocks):
```
All time are ms
Average, StdDev, Min, Max, Samples, Test
Validation is turned off meaning that no BLS operations are performed
3450.269, 0.000, 3450.269, 3450.269, 1, Initialize DB
0.417, 0.822, 0.036, 21.098, 1400, Load block from database
16.521, 0.000, 16.521, 16.521, 1, Load state from database
27.906, 50.846, 8.104, 1507.633, 1350, Apply block
52.617, 37.029, 20.640, 135.938, 50, Apply epoch block
```
Post:
```
3502.715, 0.000, 3502.715, 3502.715, 1, Initialize DB
0.080, 0.560, 0.035, 21.015, 1400, Load block from database
17.595, 0.000, 17.595, 17.595, 1, Load state from database
15.706, 11.028, 8.300, 107.537, 1350, Apply block
33.217, 12.622, 17.331, 60.580, 50, Apply epoch block
```
* more perf fixes
* load EpochRef cache into StateCache more aggressively
* point out security concern with public key cache
* reuse proposer index from state when processing block
* avoid genericAssign in a few more places
* don't parse key when signature is unparseable
* fix `==` overload for Eth2Digest
* preallocate validator list when getting active validators
* speed up proposer index calculation a little bit
* reuse cache when replaying blocks in ncli_db
* avoid a few more copying loops
```
Average, StdDev, Min, Max, Samples, Test
Validation is turned off meaning that no BLS operations are performed
3279.158, 0.000, 3279.158, 3279.158, 1, Initialize DB
0.072, 0.357, 0.035, 13.400, 1400, Load block from database
17.295, 0.000, 17.295, 17.295, 1, Load state from database
5.918, 9.896, 0.198, 98.028, 1350, Apply block
15.888, 10.951, 7.902, 39.535, 50, Apply epoch block
0.000, 0.000, 0.000, 0.000, 0, Database block store
```
* clear full balance cache before processing rewards and penalties
```
All time are ms
Average, StdDev, Min, Max, Samples, Test
Validation is turned off meaning that no BLS operations are performed
3947.901, 0.000, 3947.901, 3947.901, 1, Initialize DB
0.124, 0.506, 0.026, 202.370, 363345, Load block from database
97.614, 0.000, 97.614, 97.614, 1, Load state from database
0.186, 0.188, 0.012, 99.561, 357262, Advance slot, non-epoch
14.161, 5.966, 1.099, 395.511, 11524, Advance slot, epoch
1.372, 4.170, 0.017, 276.401, 363345, Apply block, no slot processing
0.000, 0.000, 0.000, 0.000, 0, Database block store
```
* detect already-aggregate-voted condition before attestation pool; add is_aggregator tests
* replace pair of attestation-per-epoch tracking lists with single list and remove Option use
* fix attestation condition
* use safer type conversions; add more is_aggregator tests
* Handle some web3 timeouts better
* Add support for developer .env files
* Eth1 improvements; Mainnet genesis state
Notable changes:
* The deposits table have been removed from the database. The client
will no longer process all deposits on start-up.
* The network metadata now includes a "state snapshot" of the deposit
contract. This allows the client to skip syncing deposits made prior
to the snapshot (i.e. genesis). Suitable metadata added for Pyrmont
and Mainnet.
* The Eth1 monitor won't be started unless there are validators attached
to the node.
* The genesis detection code is now optional and disabled by default
* Bugfix: The client should not produce blocks that will fail validation
when it hasn't downloaded the latest deposits yet
* Bugfix: Work around the database corruption affecting Pyrmont nodes
* Remove metadata for Toledo and Medalla
* log when database is loading (to avoid confusion)
* generate network keys later during startup
* fix quarantine not scheduling chain of parents for download and
increase size to one epoch
* log validator count, enr and peerid more clearly on startup
This introcudes a cache for block summaries, useful for instantiating
the block dag on startup, bringing medalla startup times down from
minutes to seconds.
This is something of a temporary band-aid that would be obsoleted by a
finalized block store.
Validators exiting is normal, no need to scream about it
* avoid reallocating seq on big exit queue
* avoid fetching state cache when updating head (it's rarely needed)
* remove incorrectly implemented live validator counts (avoids memory
allocs)
* misc memory and perf fixes
* use EpochRef for attestation aggregation
* compress effective balances in memory (medalla unfinalized: 4gb ->
1gb)
* avoid hitting db when rewinding to head or clearance state
* avoid hitting db when blocks can be applied to in-memory state -
speeds up startup considerably
* avoid storing epochref in fork choice
* simplify and speed up beacon block creation flow - avoids state reload
thanks to head rewind optimization
* iterator-based committee and attestation participation help avoid lots
of small memory allocations throughout epoch transition (40% speedup on
epoch processing, for example during startup)
* add constant for threshold
* update attestation extended validation to v1.0.0-rc.0
* attestation block and target must be within same epoch
* remove duplicate attestation epoch/target epoch check
* in spec now
It turns out that we often save lots of states in the database that are
the result of empty slot processing only - here, we make sure to only
save a state if a block follows - this fixes several issues:
* empty slot states are not always pruned leading to state database size
explosion
* storing states is (very) slow which slows down processing in general,
so we should only do it when it's likely to be useful
* attestation processing doesn't get stuck on saving random states that
won't appear in the chain history
* remove some superfluous gcsafes
* remove getTailState (unused)
* don't store old epochrefs in blocks
* document attestation pool a bit
* remove `pcs =` cruft from log
* add ncli_db subcommand to prune database of unnecessary blocks, states, and state roots
* tweak comments
* reduce default aggressiveness in pruning old states
* move copyPrunedDatabase() to ncli_db, as it's not generally useful as part of beacon_chain_db and doesn't use any internal interfaces
* Quick fix to prune some states, pending smarter state storage
Adverse effects might include slow rewinds - typically the protocol
doesn't ask for pre-finalized states but RPC might
* document issue, add test
* fix cache miss log
* stop discarding non-existent future epochs during epoch state transitions; remove a pointless StateCache() construction in advance_slots()
* update nbench to pass StateCache to process_slots()