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](de2b2801c8/data/beaconrestapi/src/main/java/tech/pegasys/teku/beaconrestapi/handlers/v1/events/EventSubscriptionManager.java (L171-L182)
) it uses [`getStateRootFromBlockRoot`](de2b2801c8/data/provider/src/main/java/tech/pegasys/teku/api/ChainDataProvider.java (L336-L341)
) which uses (1). I have switched Lighthouse from (2) to (1). I think it's a somewhat arbitrary choice between the two, where (1) is easier to compute and is consistent with Teku. ## Notes for Reviewers I've renamed `BeaconChain::fork_choice` to `BeaconChain::recompute_head`. Doing this helped ensure I broke all previous uses of fork choice and I also find it more descriptive. It describes an action and can't be confused with trying to get a reference to the `ForkChoice` struct. I've changed the ordering of SSE events when a block is received. It used to be `[block, finalized, head]` and now it's `[block, head, finalized]`. It was easier this way and I don't think we were making any promises about SSE event ordering so it's not "breaking". I've made it so fork choice will run when it's first constructed. I did this because I wanted to have a cached version of the last call to `get_head`. Ensuring `get_head` has been run *at least once* means that the cached values doesn't need to wrapped in an `Option`. This was fairly simple, it just involved passing a `slot` to the constructor so it knows *when* it's being run. When loading a fork choice from the store and a slot clock isn't handy I've just used the `slot` that was saved in the `fork_choice_store`. That seems like it would be a faithful representation of the slot when we saved it. I added the `genesis_time: u64` to the `BeaconChain`. It's small, constant and nice to have around. Since we're using FC for the fin/just checkpoints, we no longer get the `0x00..00` roots at genesis. You can see I had to remove a work-around in `ef-tests` here: b56be3bc2. I can't find any reason why this would be an issue, if anything I think it'll be better since the genesis-alias has caught us out a few times (0x00..00 isn't actually a real root). Edit: I did find a case where the `network` expected the 0x00..00 alias and patched it here: 3f26ac3e2. You'll notice a lot of changes in tests. Generally, tests should be functionally equivalent. Here are the things creating the most diff-noise in tests: - Changing tests to be `tokio::async` tests. - Adding `.await` to fork choice, block processing and block production functions. - Refactor of the `canonical_head` "API" provided by the `BeaconChain`. E.g., `chain.canonical_head.cached_head()` instead of `chain.canonical_head.read()`. - Wrapping `SignedBeaconBlock` in an `Arc`. - In the `beacon_chain/tests/block_verification`, we can't use the `lazy_static` `CHAIN_SEGMENT` variable anymore since it's generated with an async function. We just generate it in each test, not so efficient but hopefully insignificant. I had to disable `rayon` concurrent tests in the `fork_choice` tests. This is because the use of `rayon` and `block_on` was causing a panic. Co-authored-by: Mac L <mjladson@pm.me>
133 lines
4.5 KiB
Rust
133 lines
4.5 KiB
Rust
//! Generic tests that make use of the (newer) `InteractiveApiTester`
|
|
use crate::common::*;
|
|
use beacon_chain::test_utils::{AttestationStrategy, BlockStrategy};
|
|
use eth2::types::DepositContractData;
|
|
use tree_hash::TreeHash;
|
|
use types::{EthSpec, FullPayload, MainnetEthSpec, Slot};
|
|
|
|
type E = MainnetEthSpec;
|
|
|
|
// Test that the deposit_contract endpoint returns the correct chain_id and address.
|
|
// Regression test for https://github.com/sigp/lighthouse/issues/2657
|
|
#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
|
|
async fn deposit_contract_custom_network() {
|
|
let validator_count = 24;
|
|
let mut spec = E::default_spec();
|
|
|
|
// Rinkeby, which we don't use elsewhere.
|
|
spec.deposit_chain_id = 4;
|
|
spec.deposit_network_id = 4;
|
|
// Arbitrary contract address.
|
|
spec.deposit_contract_address = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa".parse().unwrap();
|
|
|
|
let tester = InteractiveTester::<E>::new(Some(spec.clone()), validator_count).await;
|
|
let client = &tester.client;
|
|
|
|
let result = client.get_config_deposit_contract().await.unwrap().data;
|
|
|
|
let expected = DepositContractData {
|
|
address: spec.deposit_contract_address,
|
|
chain_id: spec.deposit_chain_id,
|
|
};
|
|
|
|
assert_eq!(result, expected);
|
|
}
|
|
|
|
// Test that running fork choice before proposing results in selection of the correct head.
|
|
#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
|
|
pub async fn fork_choice_before_proposal() {
|
|
// Validator count needs to be at least 32 or proposer boost gets set to 0 when computing
|
|
// `validator_count // 32`.
|
|
let validator_count = 32;
|
|
let all_validators = (0..validator_count).collect::<Vec<_>>();
|
|
let num_initial: u64 = 31;
|
|
|
|
let tester = InteractiveTester::<E>::new(None, validator_count).await;
|
|
let harness = &tester.harness;
|
|
|
|
// Create some chain depth.
|
|
harness.advance_slot();
|
|
harness
|
|
.extend_chain(
|
|
num_initial as usize,
|
|
BlockStrategy::OnCanonicalHead,
|
|
AttestationStrategy::AllValidators,
|
|
)
|
|
.await;
|
|
|
|
// We set up the following block graph, where B is a block that is temporarily orphaned by C,
|
|
// but is then reinstated and built upon by D.
|
|
//
|
|
// A | B | - | D |
|
|
// ^ | - | C |
|
|
let slot_a = Slot::new(num_initial);
|
|
let slot_b = slot_a + 1;
|
|
let slot_c = slot_a + 2;
|
|
let slot_d = slot_a + 3;
|
|
|
|
let state_a = harness.get_current_state();
|
|
let (block_b, state_b) = harness.make_block(state_a.clone(), slot_b).await;
|
|
let block_root_b = harness.process_block(slot_b, block_b).await.unwrap();
|
|
|
|
// Create attestations to B but keep them in reserve until after C has been processed.
|
|
let attestations_b = harness.make_attestations(
|
|
&all_validators,
|
|
&state_b,
|
|
state_b.tree_hash_root(),
|
|
block_root_b,
|
|
slot_b,
|
|
);
|
|
|
|
let (block_c, state_c) = harness.make_block(state_a, slot_c).await;
|
|
let block_root_c = harness
|
|
.process_block(slot_c, block_c.clone())
|
|
.await
|
|
.unwrap();
|
|
|
|
// Create attestations to C from a small number of validators and process them immediately.
|
|
let attestations_c = harness.make_attestations(
|
|
&all_validators[..validator_count / 2],
|
|
&state_c,
|
|
state_c.tree_hash_root(),
|
|
block_root_c,
|
|
slot_c,
|
|
);
|
|
harness.process_attestations(attestations_c);
|
|
|
|
// Apply the attestations to B, but don't re-run fork choice.
|
|
harness.process_attestations(attestations_b);
|
|
|
|
// Due to proposer boost, the head should be C during slot C.
|
|
assert_eq!(
|
|
harness.chain.canonical_head.cached_head().head_block_root(),
|
|
block_root_c.into()
|
|
);
|
|
|
|
// Ensure that building a block via the HTTP API re-runs fork choice and builds block D upon B.
|
|
// Manually prod the per-slot task, because the slot timer doesn't run in the background in
|
|
// these tests.
|
|
harness.advance_slot();
|
|
harness.chain.per_slot_task().await;
|
|
|
|
let proposer_index = state_b
|
|
.get_beacon_proposer_index(slot_d, &harness.chain.spec)
|
|
.unwrap();
|
|
let randao_reveal = harness
|
|
.sign_randao_reveal(&state_b, proposer_index, slot_d)
|
|
.into();
|
|
let block_d = tester
|
|
.client
|
|
.get_validator_blocks::<E, FullPayload<E>>(slot_d, &randao_reveal, None)
|
|
.await
|
|
.unwrap()
|
|
.data;
|
|
|
|
// Head is now B.
|
|
assert_eq!(
|
|
harness.chain.canonical_head.cached_head().head_block_root(),
|
|
block_root_b.into()
|
|
);
|
|
// D's parent is B.
|
|
assert_eq!(block_d.parent_root(), block_root_b.into());
|
|
}
|