## Issue Addressed
Solution 2 proposed here: https://github.com/sigp/lighthouse/issues/1435#issuecomment-692317639
## Proposed Changes
- Adds an optional `--wss-checkpoint` flag that takes a string `root:epoch`
- Verify that the given checkpoint exists in the chain, or that the the chain syncs through this checkpoint. If not, shutdown and prompt the user to purge state before restarting.
## Additional Info
Co-authored-by: Paul Hauner <paul@paulhauner.com>
## Issue Addressed
NA
## Proposed Changes
There are four new conditions introduced in v0.12.3:
1. _[REJECT]_ The attestation's epoch matches its target -- i.e. `attestation.data.target.epoch ==
compute_epoch_at_slot(attestation.data.slot)`
1. _[REJECT]_ The attestation's target block is an ancestor of the block named in the LMD vote -- i.e.
`get_ancestor(store, attestation.data.beacon_block_root, compute_start_slot_at_epoch(attestation.data.target.epoch)) == attestation.data.target.root`
1. _[REJECT]_ The committee index is within the expected range -- i.e. `data.index < get_committee_count_per_slot(state, data.target.epoch)`.
1. _[REJECT]_ The number of aggregation bits matches the committee size -- i.e.
`len(attestation.aggregation_bits) == len(get_beacon_committee(state, data.slot, data.index))`.
This PR implements new logic to suit (1) and (2). Tests are added for (3) and (4), although they were already implicitly enforced.
## Additional Info
- There's a bit of edge-case with target root verification that I raised here: https://github.com/ethereum/eth2.0-specs/pull/2001#issuecomment-699246659
- I've had to add an `--ignore` to `cargo audit` to get CI to pass. See https://github.com/sigp/lighthouse/issues/1669
## Issue Addressed
In principle.. closes#1551 but in general are improvements for performance, maintainability and readability. The logic for the optimistic sync in actually simple
## Proposed Changes
There are miscellaneous things here:
- Remove unnecessary `BatchProcessResult::Partial` to simplify the batch validation logic
- Make batches a state machine. This is done to ensure batch state transitions respect our logic (this was previously done by moving batches between `Vec`s) and to ease the cognitive load of the `SyncingChain` struct
- Move most batch-related logic to the batch
- Remove `PendingBatches` in favor of a map of peers to their batches. This is to avoid duplicating peers inside the chain (peer_pool and pending_batches)
- Add `must_use` decoration to the `ProcessingResult` so that chains that request to be removed are handled accordingly. This also means that chains are now removed in more places than before to account for unhandled cases
- Store batches in a sorted map (`BTreeMap`) access is not O(1) but since the number of _active_ batches is bounded this should be fast, and saves performing hashing ops. Batches are indexed by the epoch they start. Sorted, to easily handle chain advancements (range logic)
- Produce the chain Id from the identifying fields: target root and target slot. This, to guarantee there can't be duplicated chains and be able to consistently search chains by either Id or checkpoint
- Fix chain_id not being present in all chain loggers
- Handle mega-edge case where the processor's work queue is full and the batch can't be sent. In this case the chain would lose the blocks, remain in a "syncing" state and waiting for a result that won't arrive, effectively stalling sync.
- When a batch imports blocks or the chain starts syncing with a local finalized epoch greater that the chain's start epoch, the chain is advanced instead of reset. This is to avoid losing download progress and validate batches faster. This also means that the old `start_epoch` now means "current first unvalidated batch", so it represents more accurately the progress of the chain.
- Batch status peers from the same chain to reduce Arc access.
- Handle a couple of cases where the retry counters for a batch were not updated/checked are now handled via the batch state machine. Basically now if we forget to do it, we will know.
- Do not send back the blocks from the processor to the batch. Instead register the attempt before sending the blocks (does not count as failed)
- When re-requesting a batch, try to avoid not only the last failed peer, but all previous failed peers.
- Optimize requesting batches ahead in the buffer by shuffling idle peers just once (this is just addressing a couple of old TODOs in the code)
- In chain_collection, store chains by their id in a map
- Include a mapping from request_ids to (chain, batch) that requested the batch to avoid the double O(n) search on block responses
- Other stuff:
- impl `slog::KV` for batches
- impl `slog::KV` for syncing chains
- PSA: when logging, we can use `%thing` if `thing` implements `Display`. Same for `?` and `Debug`
### Optimistic syncing:
Try first the batch that contains the current head, if the batch imports any block, advance the chain. If not, if this optimistic batch is inside the current processing window leave it there for future use, if not drop it. The tolerance for this block is the same for downloading, but just once for processing
Co-authored-by: Age Manning <Age@AgeManning.com>
## Issue Addressed
N/A
## Proposed Changes
Prevent subscribing to core gossipsub topics until after we have achieved a full sync. This prevents us censoring gossipsub channels, getting penalised in gossipsub 1.1 scoring and saves us computation time in attempting to validate gossipsub messages which we will be unable to do with a non-sync'd chain.
## Issue Addressed
N/A
## Proposed Changes
Shifts the local `metadata` to `network_globals` making it accessible to the HTTP API and other areas of lighthouse.
## Additional Info
N/A
## Issue Addressed
#1590
## Proposed Changes
This is a temporary workaround that prevents finalized chain sync from swapping chains. I'm merging this in now until the full solution is ready.
## Issue Addressed
Malicious users could request very large block ranges, more than we expect. Although technically legal, we are now quadraticaly weighting large step sizes in the filter. Therefore users may request large skips, but not a large number of blocks, to prevent requests forcing us to do long chain lookups.
## Proposed Changes
Weight the step parameter in the RPC filter and prevent any overflows that effect us in the step parameter.
## Additional Info
## Issue Addressed
N/A
## Proposed Changes
Adds extended metrics to get a better idea of what is happening at the gossipsub layer of lighthouse. This provides information about mesh statistics per topics, subscriptions and peer scores.
## Additional Info
## Issue Addressed
#1172
## Proposed Changes
* updates the libp2p dependency
* small adaptions based on changes in libp2p
* report not just valid messages but also invalid and distinguish between `IGNORE`d messages and `REJECT`ed messages
Co-authored-by: Age Manning <Age@AgeManning.com>
The PR:
* Adds the ability to generate a crucial test scenario that isn't possible with `BeaconChainHarness` (i.e. two blocks occupying the same slot; previously forks necessitated skipping slots):
* New testing API: Instead of repeatedly calling add_block(), you generate a sorted `Vec<Slot>` and leave it up to the framework to generate blocks at those slots.
* Jumping backwards to an earlier epoch is a hard error, so that tests necessarily generate blocks in a epoch-by-epoch manner.
* Configures the test logger so that output is printed on the console in case a test fails. The logger also plays well with `--nocapture`, contrary to the existing testing framework
* Rewrites existing fork pruning tests to use the new API
* Adds a tests that triggers finalization at a non epoch boundary slot
* Renamed `BeaconChainYoke` to `BeaconChainTestingRig` because the former has been too confusing
* Fixed multiple tests (e.g. `block_production_different_shuffling_long`, `delete_blocks_and_states`, `shuffling_compatible_simple_fork`) that relied on a weird (and accidental) feature of the old `BeaconChainHarness` that attestations aren't produced for epochs earlier than the current one, thus masking potential bugs in test cases.
Co-authored-by: Michael Sproul <michael@sigmaprime.io>
## Issue Addressed
N/A
## Proposed Changes
Refactor attestation service to send out requests to find peers for subnets as soon as we get attestation duties.
Earlier, we had much more involved logic to send the discovery requests to the discovery service only 6 slots before the attestation slot. Now that discovery is much smarter with grouped queries, the complexity in attestation service can be reduced considerably.
Co-authored-by: Age Manning <Age@AgeManning.com>
## Issue Addressed
#1494
## Proposed Changes
- Give the TaskExecutor the sender side of a channel that a task can clone to request shutting down
- The receiver side of this channel is in environment and now we block until ctrl+c or an internal shutdown signal is received
- The swarm now informs when it has reached 0 listeners
- The network receives this message and requests the shutdown
## Issue Addressed
NA
## Proposed Changes
- Refactors the `BeaconProcessor` to remove some excessive nesting and file bloat
- Sorry about the noise from this, it's all contained in 4d3f8c5 though.
- Adds exits, proposer slashings, attester slashings to the `BeaconProcessor` so we don't get overwhelmed with large amounts of slashings (which happened a few hours ago).
## Additional Info
NA
## Description
This PR improves some logging for the end-user.
It downgrades some warning logs and removes the slots per second sync speed if we are syncing and the speed is 0. This is likely because we are syncing from a finalised checkpoint and the head doesn't change.
## Description
There can be many head chains queued up to complete. Currently we try and process all of these to completion before we consider the node synced.
In a chaotic network, there can be many of these and processing them to completion can be very expensive and slow. This PR removes any non-syncing head chains from the queue, and re-status's the peers. If, after we have synced to head on one chain, there is still a valid head chain to download, it will be re-established once the status has been returned.
This should assist with getting nodes to sync on medalla faster.
## Overview
There are forked chains which get referenced by blocks and attestations on a network. Typically if these chains are very long, we stop looking up the chain and downvote the peer. In extreme circumstances, many peers are on many chains, the chains can be very deep and become time consuming performing lookups.
This PR adds a cache to known failed chain lookups. This prevents us from starting a parent-lookup (or stopping one half way through) if we have attempted the chain lookup in the past.
## Description
Currently lighthouse load-balances across peers a single finalized chain. The chain is selected via the most peers. Once synced to the latest finalized epoch Lighthouse creates chains amongst its peers and syncs them all in parallel amongst each peer (grouped by their current head block).
This is typically fast and relatively efficient under normal operations. However if the chain has not finalized in a long time, the head chains can grow quite long. Peer's head chains will update every slot as new blocks are added to the head. Syncing all head chains in parallel is a bottleneck and highly inefficient in block duplication leads to RPC timeouts when attempting to handle all new heads chains at once.
This PR limits the parallelism of head syncing chains to 2. We now sync at most two head chains at a time. This allows for the possiblity of sync progressing alongside a peer being slow and holding up one chain via RPC timeouts.
The changes are somewhat simple but should solve two issues:
- When quickly changing between chains once and a second time back again, batchIds would collide and cause havoc.
- If we got an out of range response from a peer, sync would remain in syncing but without advancing
Changes:
- remove the batch id. Identify each batch (inside a chain) by its starting epoch. Target epochs for downloading and processing now advance by EPOCHS_PER_BATCH
- for the same reason, move the "to_be_downloaded_id" to be an epoch
- remove a sneaky line that dropped an out of range batch without downloading it
- bonus: put the chain_id in the log given to the chain. This is why explicitly logging the chain_id is removed
## Proposed Changes
To mitigate the impact of minority forks on RAM and disk usage, this change rejects blocks whose parent lies more than 320 slots (10 epochs, ~1 hour) in the past. The behaviour is configurable via `lighthouse bn --max-skip-slots N`, and can be turned off entirely using `--max-skip-slots none`.
Co-authored-by: Paul Hauner <paul@paulhauner.com>
## Issue Addressed
NA
## Proposed Changes
Moves beacon block processing over to the newly-added `GossipProcessor`. This moves the task off the core executor onto the blocking one.
## Additional Info
- With this PR, gossip blocks are being ignored during sync.
## Issue Addressed
#1384
Only catch, as currently implemented, when dialing the multiaddr nodes, there is no way to ask the peer manager if they are already connected or dialing
## Issue Addressed
N/A
## Proposed Changes
Introduces the `GossipProcessor`, a multi-threaded (multi-tasked?), non-blocking processor for some messages from the network which require verification and import into the `BeaconChain`.
Initial testing indicates that this massively improves system stability by (a) moving block tasks from the normal executor (b) spreading out attestation load.
## Additional Info
TBC
## Issue Addressed
#1028
A bit late, but I think if `BlockError` had a kind (the current `BlockError` minus everything on the variants that comes directly from the block) and the original block, more clones could be removed
## Issue Addressed
Sync was breaking occasionally. The root cause appears to be identify crashing as events we being sent to the protocol after nodes were banned. Have not been able to reproduce sync issues since this update.
## Proposed Changes
Only send messages to sub-behaviour protocols if the peer manager thinks the peer is connected. All other messages are dropped.
## Issue Addressed
Recurring sync loop and invalid batch downloading
## Proposed Changes
Shifts the batches to include the first slot of each epoch. This ensures the finalized is always downloaded once a chain has completed syncing.
Also add in logic to prevent re-dialing disconnected peers. Non-performant peers get disconnected during sync, this prevents re-connection to these during sync.
## Additional Info
N/A
## Issue Addressed
N/A
## Proposed Changes
This provides a number of corrections and improvements to gossipsub. Specifically
- Enables options for greater privacy around the message author
- Provides greater flexibility on message validation
- Prevents unvalidated messages from being gossiped
- Shifts the duplicate cache to a time-based cache inside gossipsub
- Updates the message-id to handle bytes
- Bug fixes related to mesh maintenance and topic subscription. This should improve our attestation inclusion rate.
## Issue Addressed
#1388 partially (eth2_libp2p & network)
## Proposed Changes
TLDR at the end
- *Complex types* are 3 on the handlers/Behaviours but the types are `Poll<ComplexType>` where `ComplexType` comes from the traits of libp2p. Those, I don't thing are worth an alias. A couple more were from using tokio combinators and were removed writing things the async way and using [`BoxFuture`](https://docs.rs/futures/0.3.5/futures/future/type.BoxFuture.html)
- The *cognitive complexity*.. I tried to address those before (they come from the poll functions too) and tbh they are cognitively simpler to understand the way they are now. Moving separate parts to functions doesn't add much since that code is not repeated and they all do early returns. If moved those returns would now need to be wrapped in an Option, probably, and checked to be returned again. I would leave them like that but that's just preference.
- *Too many arguments*: They are not easily put together in a wrapping struct since the parameters don't relate semantically (Ex: fn new with a log, a reference to the chain, a peer, etc) but some may differ.
- *Needless returns* were indeed needless
## Additional Info
TLDR: removed needless return, used BoxFuture and async, left the rest untouched since those lgtm
