be4e261e74
## Overview
This rather extensive PR achieves two primary goals:
1. Uses the finalized/justified checkpoints of fork choice (FC), rather than that of the head state.
2. Refactors fork choice, block production and block processing to `async` functions.
Additionally, it achieves:
- Concurrent forkchoice updates to the EL and cache pruning after a new head is selected.
- Concurrent "block packing" (attestations, etc) and execution payload retrieval during block production.
- Concurrent per-block-processing and execution payload verification during block processing.
- The `Arc`-ification of `SignedBeaconBlock` during block processing (it's never mutated, so why not?):
- I had to do this to deal with sending blocks into spawned tasks.
- Previously we were cloning the beacon block at least 2 times during each block processing, these clones are either removed or turned into cheaper `Arc` clones.
- We were also `Box`-ing and un-`Box`-ing beacon blocks as they moved throughout the networking crate. This is not a big deal, but it's nice to avoid shifting things between the stack and heap.
- Avoids cloning *all the blocks* in *every chain segment* during sync.
- It also has the potential to clean up our code where we need to pass an *owned* block around so we can send it back in the case of an error (I didn't do much of this, my PR is already big enough 😅)
- The `BeaconChain::HeadSafetyStatus` struct was removed. It was an old relic from prior merge specs.
For motivation for this change, see https://github.com/sigp/lighthouse/pull/3244#issuecomment-1160963273
## Changes to `canonical_head` and `fork_choice`
Previously, the `BeaconChain` had two separate fields:
```
canonical_head: RwLock<Snapshot>,
fork_choice: RwLock<BeaconForkChoice>
```
Now, we have grouped these values under a single struct:
```
canonical_head: CanonicalHead {
cached_head: RwLock<Arc<Snapshot>>,
fork_choice: RwLock<BeaconForkChoice>
}
```
Apart from ergonomics, the only *actual* change here is wrapping the canonical head snapshot in an `Arc`. This means that we no longer need to hold the `cached_head` (`canonical_head`, in old terms) lock when we want to pull some values from it. This was done to avoid deadlock risks by preventing functions from acquiring (and holding) the `cached_head` and `fork_choice` locks simultaneously.
## Breaking Changes
### The `state` (root) field in the `finalized_checkpoint` SSE event
Consider the scenario where epoch `n` is just finalized, but `start_slot(n)` is skipped. There are two state roots we might in the `finalized_checkpoint` SSE event:
1. The state root of the finalized block, which is `get_block(finalized_checkpoint.root).state_root`.
4. The state root at slot of `start_slot(n)`, which would be the state from (1), but "skipped forward" through any skip slots.
Previously, Lighthouse would choose (2). However, we can see that when [Teku generates that event](
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| src | ||
| tests | ||
| .gitignore | ||
| Cargo.toml | ||
| check_all_files_accessed.py | ||
| Makefile | ||
| README.md | ||
Consensus Specification Tests
This crate parses and executes the test vectors at ethereum/consensus-spec-tests.
Functionality is achieved only via the $ cargo test --features ef_tests command.
Running the Tests
Because the test vectors are very large, we do not download or run them by default. To download them, run (in this directory):
$ make
Note: this may download hundreds of MB of compressed archives from the ethereum/consensus-spec-tests, which may expand into several GB of files.
If successful, you should now have the extracted tests in ./consensus-spec-tests.
Run them with:
$ cargo test --features ef_tests
The tests won't run without the ef_tests feature enabled (this is to ensure that a top-level
cargo test --all won't fail on missing files).
Saving Space
When you download the tests, the downloaded archives will be kept in addition to the extracted files. You have several options for saving space:
- Delete the archives (
make clean-archives), and keep the extracted files. Suitable for everyday use, just don't re-runmakeor it will redownload the archives. - Delete the extracted files (
make clean-test-files), and keep the archives. Suitable for CI, or temporarily saving space. If you re-runmakeit will extract the archives rather than redownloading them. - Delete everything (
make clean). Good for updating to a new version, or if you no longer wish to run the EF tests.