gnosis/lighthouse
1
0
Fork 0
mirror of https://github.com/sigp/lighthouse.git synced 2026-03-11 18:04:18 +00:00
Code Issues Packages Projects Releases Wiki Activity

Use async code when interacting with EL (#3244)

Browse Source 
## 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>
This commit is contained in:
Paul Hauner
2022-07-03 05:36:50 +00:00
parent e5212f1320
commit be4e261e74
106 changed files with 6515 additions and 4538 deletions
Download Patch File Download Diff File Expand all files Collapse all files

72
beacon_node/lighthouse_network/src/rpc/codec/ssz_snappy.rs
View File

@@ -532,10 +532,10 @@ fn handle_v1_response<T: EthSpec>(
Protocol::Goodbye => Err(RPCError::InvalidData(
"Goodbye RPC message has no valid response".to_string(),
)),
Protocol::BlocksByRange => Ok(Some(RPCResponse::BlocksByRange(Box::new(
Protocol::BlocksByRange => Ok(Some(RPCResponse::BlocksByRange(Arc::new(
SignedBeaconBlock::Base(SignedBeaconBlockBase::from_ssz_bytes(decoded_buffer)?),
)))),
Protocol::BlocksByRoot => Ok(Some(RPCResponse::BlocksByRoot(Box::new(
Protocol::BlocksByRoot => Ok(Some(RPCResponse::BlocksByRoot(Arc::new(
SignedBeaconBlock::Base(SignedBeaconBlockBase::from_ssz_bytes(decoded_buffer)?),
)))),
Protocol::Ping => Ok(Some(RPCResponse::Pong(Ping {
@@ -572,31 +572,31 @@ fn handle_v2_response<T: EthSpec>(
})?;
match protocol {
Protocol::BlocksByRange => match fork_name {
ForkName::Altair => Ok(Some(RPCResponse::BlocksByRange(Box::new(
ForkName::Altair => Ok(Some(RPCResponse::BlocksByRange(Arc::new(
SignedBeaconBlock::Altair(SignedBeaconBlockAltair::from_ssz_bytes(
decoded_buffer,
)?),
)))),
ForkName::Base => Ok(Some(RPCResponse::BlocksByRange(Box::new(
ForkName::Base => Ok(Some(RPCResponse::BlocksByRange(Arc::new(
SignedBeaconBlock::Base(SignedBeaconBlockBase::from_ssz_bytes(decoded_buffer)?),
)))),
ForkName::Merge => Ok(Some(RPCResponse::BlocksByRange(Box::new(
ForkName::Merge => Ok(Some(RPCResponse::BlocksByRange(Arc::new(
SignedBeaconBlock::Merge(SignedBeaconBlockMerge::from_ssz_bytes(
decoded_buffer,
)?),
)))),
},
Protocol::BlocksByRoot => match fork_name {
ForkName::Altair => Ok(Some(RPCResponse::BlocksByRoot(Box::new(
ForkName::Altair => Ok(Some(RPCResponse::BlocksByRoot(Arc::new(
SignedBeaconBlock::Altair(SignedBeaconBlockAltair::from_ssz_bytes(
decoded_buffer,
)?),
)))),
ForkName::Base => Ok(Some(RPCResponse::BlocksByRoot(Box::new(
ForkName::Base => Ok(Some(RPCResponse::BlocksByRoot(Arc::new(
SignedBeaconBlock::Base(SignedBeaconBlockBase::from_ssz_bytes(decoded_buffer)?),
)))),
ForkName::Merge => Ok(Some(RPCResponse::BlocksByRoot(Box::new(
ForkName::Merge => Ok(Some(RPCResponse::BlocksByRoot(Arc::new(
SignedBeaconBlock::Merge(SignedBeaconBlockMerge::from_ssz_bytes(
decoded_buffer,
)?),
@@ -898,10 +898,10 @@ mod tests {
encode_then_decode_response(
Protocol::BlocksByRange,
Version::V1,
RPCCodedResponse::Success(RPCResponse::BlocksByRange(Box::new(empty_base_block()))),
RPCCodedResponse::Success(RPCResponse::BlocksByRange(Arc::new(empty_base_block()))),
ForkName::Base,
),
Ok(Some(RPCResponse::BlocksByRange(Box::new(
Ok(Some(RPCResponse::BlocksByRange(Arc::new(
empty_base_block()
))))
);
@@ -911,7 +911,7 @@ mod tests {
encode_then_decode_response(
Protocol::BlocksByRange,
Version::V1,
RPCCodedResponse::Success(RPCResponse::BlocksByRange(Box::new(altair_block()))),
RPCCodedResponse::Success(RPCResponse::BlocksByRange(Arc::new(altair_block()))),
ForkName::Altair,
)
.unwrap_err(),
@@ -924,11 +924,11 @@ mod tests {
encode_then_decode_response(
Protocol::BlocksByRoot,
Version::V1,
RPCCodedResponse::Success(RPCResponse::BlocksByRoot(Box::new(empty_base_block()))),
RPCCodedResponse::Success(RPCResponse::BlocksByRoot(Arc::new(empty_base_block()))),
ForkName::Base,
),
Ok(Some(RPCResponse::BlocksByRoot(
Box::new(empty_base_block())
Arc::new(empty_base_block())
)))
);
@@ -937,7 +937,7 @@ mod tests {
encode_then_decode_response(
Protocol::BlocksByRoot,
Version::V1,
RPCCodedResponse::Success(RPCResponse::BlocksByRoot(Box::new(altair_block()))),
RPCCodedResponse::Success(RPCResponse::BlocksByRoot(Arc::new(altair_block()))),
ForkName::Altair,
)
.unwrap_err(),
@@ -1013,10 +1013,10 @@ mod tests {
encode_then_decode_response(
Protocol::BlocksByRange,
Version::V2,
RPCCodedResponse::Success(RPCResponse::BlocksByRange(Box::new(empty_base_block()))),
RPCCodedResponse::Success(RPCResponse::BlocksByRange(Arc::new(empty_base_block()))),
ForkName::Base,
),
Ok(Some(RPCResponse::BlocksByRange(Box::new(
Ok(Some(RPCResponse::BlocksByRange(Arc::new(
empty_base_block()
))))
);
@@ -1028,10 +1028,10 @@ mod tests {
encode_then_decode_response(
Protocol::BlocksByRange,
Version::V2,
RPCCodedResponse::Success(RPCResponse::BlocksByRange(Box::new(empty_base_block()))),
RPCCodedResponse::Success(RPCResponse::BlocksByRange(Arc::new(empty_base_block()))),
ForkName::Altair,
),
Ok(Some(RPCResponse::BlocksByRange(Box::new(
Ok(Some(RPCResponse::BlocksByRange(Arc::new(
empty_base_block()
))))
);
@@ -1040,10 +1040,10 @@ mod tests {
encode_then_decode_response(
Protocol::BlocksByRange,
Version::V2,
RPCCodedResponse::Success(RPCResponse::BlocksByRange(Box::new(altair_block()))),
RPCCodedResponse::Success(RPCResponse::BlocksByRange(Arc::new(altair_block()))),
ForkName::Altair,
),
Ok(Some(RPCResponse::BlocksByRange(Box::new(altair_block()))))
Ok(Some(RPCResponse::BlocksByRange(Arc::new(altair_block()))))
);
let merge_block_small = merge_block_small(&fork_context(ForkName::Merge));
@@ -1053,12 +1053,12 @@ mod tests {
encode_then_decode_response(
Protocol::BlocksByRange,
Version::V2,
RPCCodedResponse::Success(RPCResponse::BlocksByRange(Box::new(
RPCCodedResponse::Success(RPCResponse::BlocksByRange(Arc::new(
merge_block_small.clone()
))),
ForkName::Merge,
),
Ok(Some(RPCResponse::BlocksByRange(Box::new(
Ok(Some(RPCResponse::BlocksByRange(Arc::new(
merge_block_small.clone()
))))
);
@@ -1085,11 +1085,11 @@ mod tests {
encode_then_decode_response(
Protocol::BlocksByRoot,
Version::V2,
RPCCodedResponse::Success(RPCResponse::BlocksByRoot(Box::new(empty_base_block()))),
RPCCodedResponse::Success(RPCResponse::BlocksByRoot(Arc::new(empty_base_block()))),
ForkName::Base,
),
Ok(Some(RPCResponse::BlocksByRoot(
Box::new(empty_base_block())
Arc::new(empty_base_block())
))),
);
@@ -1100,11 +1100,11 @@ mod tests {
encode_then_decode_response(
Protocol::BlocksByRoot,
Version::V2,
RPCCodedResponse::Success(RPCResponse::BlocksByRoot(Box::new(empty_base_block()))),
RPCCodedResponse::Success(RPCResponse::BlocksByRoot(Arc::new(empty_base_block()))),
ForkName::Altair,
),
Ok(Some(RPCResponse::BlocksByRoot(
Box::new(empty_base_block())
Arc::new(empty_base_block())
)))
);
@@ -1112,22 +1112,22 @@ mod tests {
encode_then_decode_response(
Protocol::BlocksByRoot,
Version::V2,
RPCCodedResponse::Success(RPCResponse::BlocksByRoot(Box::new(altair_block()))),
RPCCodedResponse::Success(RPCResponse::BlocksByRoot(Arc::new(altair_block()))),
ForkName::Altair,
),
Ok(Some(RPCResponse::BlocksByRoot(Box::new(altair_block()))))
Ok(Some(RPCResponse::BlocksByRoot(Arc::new(altair_block()))))
);
assert_eq!(
encode_then_decode_response(
Protocol::BlocksByRoot,
Version::V2,
RPCCodedResponse::Success(RPCResponse::BlocksByRoot(Box::new(
RPCCodedResponse::Success(RPCResponse::BlocksByRoot(Arc::new(
merge_block_small.clone()
))),
ForkName::Merge,
),
Ok(Some(RPCResponse::BlocksByRoot(Box::new(merge_block_small))))
Ok(Some(RPCResponse::BlocksByRoot(Arc::new(merge_block_small))))
);
let mut encoded =
@@ -1179,7 +1179,7 @@ mod tests {
let mut encoded_bytes = encode_response(
Protocol::BlocksByRange,
Version::V2,
RPCCodedResponse::Success(RPCResponse::BlocksByRange(Box::new(empty_base_block()))),
RPCCodedResponse::Success(RPCResponse::BlocksByRange(Arc::new(empty_base_block()))),
ForkName::Base,
)
.unwrap();
@@ -1200,7 +1200,7 @@ mod tests {
let mut encoded_bytes = encode_response(
Protocol::BlocksByRoot,
Version::V2,
RPCCodedResponse::Success(RPCResponse::BlocksByRoot(Box::new(empty_base_block()))),
RPCCodedResponse::Success(RPCResponse::BlocksByRoot(Arc::new(empty_base_block()))),
ForkName::Base,
)
.unwrap();
@@ -1222,7 +1222,7 @@ mod tests {
let mut encoded_bytes = encode_response(
Protocol::BlocksByRange,
Version::V2,
RPCCodedResponse::Success(RPCResponse::BlocksByRange(Box::new(empty_base_block()))),
RPCCodedResponse::Success(RPCResponse::BlocksByRange(Arc::new(empty_base_block()))),
ForkName::Altair,
)
.unwrap();
@@ -1247,7 +1247,7 @@ mod tests {
let mut encoded_bytes = encode_response(
Protocol::BlocksByRoot,
Version::V2,
RPCCodedResponse::Success(RPCResponse::BlocksByRoot(Box::new(altair_block()))),
RPCCodedResponse::Success(RPCResponse::BlocksByRoot(Arc::new(altair_block()))),
ForkName::Altair,
)
.unwrap();
@@ -1292,7 +1292,7 @@ mod tests {
let mut encoded_bytes = encode_response(
Protocol::BlocksByRoot,
Version::V2,
RPCCodedResponse::Success(RPCResponse::BlocksByRoot(Box::new(empty_base_block()))),
RPCCodedResponse::Success(RPCResponse::BlocksByRoot(Arc::new(empty_base_block()))),
ForkName::Altair,
)
.unwrap();
@@ -1316,7 +1316,7 @@ mod tests {
let mut encoded_bytes = encode_response(
Protocol::BlocksByRoot,
Version::V2,
RPCCodedResponse::Success(RPCResponse::BlocksByRoot(Box::new(empty_base_block()))),
RPCCodedResponse::Success(RPCResponse::BlocksByRoot(Arc::new(empty_base_block()))),
ForkName::Altair,
)
.unwrap();

5
beacon_node/lighthouse_network/src/rpc/methods.rs
View File

@@ -9,6 +9,7 @@ use ssz_types::{
VariableList,
};
use std::ops::Deref;
use std::sync::Arc;
use strum::IntoStaticStr;
use superstruct::superstruct;
use types::{Epoch, EthSpec, Hash256, SignedBeaconBlock, Slot};
@@ -237,10 +238,10 @@ pub enum RPCResponse<T: EthSpec> {
/// A response to a get BLOCKS_BY_RANGE request. A None response signifies the end of the
/// batch.
BlocksByRange(Box<SignedBeaconBlock<T>>),
BlocksByRange(Arc<SignedBeaconBlock<T>>),
/// A response to a get BLOCKS_BY_ROOT request.
BlocksByRoot(Box<SignedBeaconBlock<T>>),
BlocksByRoot(Arc<SignedBeaconBlock<T>>),
/// A PONG response to a PING request.
Pong(Ping),