When the network is partitioned for a long time, e.g., Goerli, branches
start forming where different peers have distinct views about the chain
state. The current syncing solution with sync manager doesn't handle the
case well, as it is optimized for a healthy network where syncing can be
parallelized across different peers. To support sync manager discovering
additional branches, a new module is added that pulls in histories from
peers on unknown branches in a backwards manner.
There can be situations where proposals need to be made on top of stale
parent state. Because the distance to the wall slot is big, the proposal
state (`getProposalState`) has to be computed incrementally to avoid lag
spikes. Proposals have to be timely to have a chance to propagate on the
network. Peak memory requirements don't change, but the proposal state
needs to be allocated for a longer duration than usual.
The `syncHorizon` describes the number of empty slots before the beacon
node considers itself to be out of sync. There are two places where we
currently set this to 50 slots, but it makes more sense to base it on
wall time, e.g., the 10 minutes that the default 50 are derived from.
Extend slot start message and default status bar with information about
current head fork and the next fork transition (corresponding to head).
This is useful to know whether a synced client is aware of a future fork
and can also be useful when syncing from old forks to follow progress
across the various forks.
```
peers: 8 ❯ finalized: 741c2ce2:230474 ❯ head: b330f58b:230477:20 ❯ fork: Capella (next: Deneb:231680) ❯ time: 230599:24 (7379192) ❯ sync: 00h24m (99.63%) 2.6492slots/s (QwQUwQPQDQ:7375263)/opt
```
```
INF 2024-01-12 12:18:00.001+01:00 Slot start topics="beacnde" slot=7379190 epoch=230599 fork="Capella (next: Deneb:231680)" sync="--h--m (99.62%) 0.0000slots/s (wwwwwwwwww:7375167)/opt" peers=0 head=741c2ce2:7375168 finalized=230472:723abe7e delay=1ms861us
```
Using trusted node sync currently requires to run two commands -
first the `trustedNodeSync` command to initialize the database,
followed by the regular startup command to continue syncing.
The `trustedNodeSync` options are now also available during regular
startup, and are used when the database is empty to simplify setting up
a new Nimbus beacon node. This also aligns behaviour closer with other
Ethereum consensus implementations.
The new logic only applies if the database has not yet been initialized;
same as before. Also, the database needs to be removed under the same
conditions as before when a fresh sync is desired.
`Eth2NetworkMetadata` has an `incompatible` case to hold an error string
in case the loaded file is not compatible with the compile-time config.
The same can be modeled with a `Result[Eth2NetworkMetadata, string]` and
avoids followup checks for the `incompatible` case.
To allow testing https://github.com/ethereum/consensus-specs/issues/3466
add support for selecting fork choice version at launch. This means we
can deploy a different logic when `DENEB_FORK_EPOCH != FAR_FUTURE_EPOCH`
that won't be used on Mainnet.
* Initial commit with both methods enabled: `poll` and `event`.
* Address review comments.
* Address review comments.
Fix copyright years.
* After bump fixes.
* use correct exception in `parseCmdArg(enr.Record)`
`parseCmdArg` is expected to raise `ValueError` but for `enr.Record` we
currently raise `ConfigurationError`. Change to `ValueError` instead.
* lint