* remove option to select Capella fork choice algo
With Deneb having run stable for quite a while now, it's time to remove
the option to select the prior fork choice algo from Capella.
* also remove usage from test
On `ELECTRA_FORK_EPOCH`, PeerDAS is not yet activated, hence the current
mechanism based on `BlobSidecar` is still in use. With EIP-7688, the
generalized indices of `BeaconBlockBody` get reindexed, changing the
length of the inclusion proof within the `BlobSidecar`. Because network
Req/Resp operations allow responses across fork boundaries, this creates
the need for a `ForkedBlobSidecar` in that layer, same as already done
for `ForkedSignedBeaconBock` for similar reasons.
Note: This PR is only needed if PeerDAS is adopted _after_ EIP-7688.
If PeerDAS is adopted _before_ EIP-7688, a similar PR may be needed for
forked columns. Coincidental `Forked` jank can only be fully avoided if
both features activate at the same epoch, actual changes to blobs aside.
Delaying EIP-7688 for sole purpose of epoch alignemnt is not worth it.
To avoid "forked" types creeping into `BlobSidecar`, move the reduction
to `BlobSidecarInfoObject` to the sole caller. The info object is fork
agnostic, so does not need "forked" if `BlobSidecar` ever updates.
Bellatrix light client data does not contain the EL block hash, so we
had to follow blocks gossip to learn the EL `block_hash` of such blocks.
Now that Bellatrix is obsolete, we can simplify EL syncing logic under
light client scenarios. Bellatrix light client data can still be used
to advance the light client sync itself, but will no longer result in
`engine_forkchoiceUpdated` calls until the sync reaches Capella. This
also frees up some memory as we no longer have to retain blocks.
* Beacon node side implementation.
* Validator client side implementation.
* Address review comments and fix the test.
* Only 400 errors could be IndexedErrorMessage, 500 errors are always ErrorMessage.
* Remove VC shutdown functionality.
* Remove magic constants.
* Make arguments more visible and disable default values.
* Address review comments.
Using a dedicated branch for researching the effectiveness of split view
scenario handling simplifies testing and avoids having partial work on
`unstable`. If we want, we can reintroduce it under a `--debug` flag at
a later time. But for now, Goerli is a rare opoprtunity to test this,
maybe just for another week or so.
- https://github.com/status-im/infra-nimbus/pull/179
In split view situation, the canonical chain may only be served by a
tiny amount of peers, and branches may span long durations. Minority
branches may still have a large weight from attestations and should
be discovered. To assist with that, add a branch discovery module that
assists in such a situation by specifically targeting peers with unknown
histories and downloading from them, in addition to sync manager work
which handles popular branches.
There are situations where all states in the `blockchain_dag` are
occupied and cannot be borrowed.
- headState: Many assumptions in the code that it cannot be advanced
- clearanceState: Resets every time a new block gets imported, including
blocks from non-canonical branches
- epochRefState: Used even more frequently than clearanceState
This means that during the catch-up mechanic where the head state is
slowly advanced to wall clock to catch up on validator duties in the
situation where the canonical head is way behind non-canonical heads,
we cannot use any of the three existing states. In that situation,
Nimbus already consumes an increased amount of memory due to all the
`BlockRef`, fork choice states and so on, so experience is degraded.
It seems reasonable to allocate a fourth state temporarily during that
mechanic, until a new proposal could be made on the canonical chain.
Note that currently, on `unstable`, proposals _do_ happen every couple
hours because sync manager doesn't manage to discover additional heads
in a split-view scenario on Goerli. However, with the branch discovery
module, new blocks are discovered all the time, and the clearanceState
may no longer be borrowed as it is reset to different branch too often.
The extra state could also find other uses in the future, e.g., for
incremental computations as in reindexing the database, or online
collection of historical light client data.
When restarting beacon node, orphaned blocks remain in the database but
on startup, only the canonical chain as selected by fork choice loads.
When a new block is discovered that builds on top of an orphaned block,
the orphaned block is re-downloaded using sync/request manager, despite
it already being present on disk. Such queries can be answered locally
to improve discovery speed of alternate forks.
Etan Kissling
tersec
Agnish Ghosh
Eugene Kabanov
Etan Kissling
Kim De Mey