Added Execution Payload from Rayonism Fork
Updated new Containers to match Merge Spec
Updated BeaconBlockBody for Merge Spec
Completed updating BeaconState and BeaconBlockBody
Modified ExecutionPayload<T> to use Transaction<T>
Mostly Finished Changes for beacon-chain.md
Added some things for fork-choice.md
Update to match new fork-choice.md/fork.md changes
ran cargo fmt
Added Missing Pieces in eth2_libp2p for Merge
fix ef test
Various Changes to Conform Closer to Merge Spec
## Issue Addressed
Closes#1996
## Proposed Changes
Run a second `Logger` via `sloggers` which logs to a file in the background with:
- separate `debug-level` for background and terminal logging
- the ability to limit log size
- rotation through a customizable number of log files
- an option to compress old log files (`.gz` format)
Add the following new CLI flags:
- `--logfile-debug-level`: The debug level of the log files
- `--logfile-max-size`: The maximum size of each log file
- `--logfile-max-number`: The number of old log files to store
- `--logfile-compress`: Whether to compress old log files
By default background logging uses the `debug` log level and saves logfiles to:
- Beacon Node: `$HOME/.lighthouse/$network/beacon/logs/beacon.log`
- Validator Client: `$HOME/.lighthouse/$network/validators/logs/validator.log`
Or, when using the `--datadir` flag:
`$datadir/beacon/logs/beacon.log` and `$datadir/validators/logs/validator.log`
Once rotated, old logs are stored like so: `beacon.log.1`, `beacon.log.2` etc.
> Note: `beacon.log.1` is always newer than `beacon.log.2`.
## Additional Info
Currently the default value of `--logfile-max-size` is 200 (MB) and `--logfile-max-number` is 5.
This means that the maximum storage space that the logs will take up by default is 1.2GB.
(200MB x 5 from old log files + <200MB the current logfile being written to)
Happy to adjust these default values to whatever people think is appropriate.
It's also worth noting that when logging to a file, we lose our custom `slog` formatting. This means the logfile logs look like this:
```
Oct 27 16:02:50.305 INFO Lighthouse started, version: Lighthouse/v2.0.1-8edd9d4+, module: lighthouse:413
Oct 27 16:02:50.305 INFO Configured for network, name: prater, module: lighthouse:414
```
## Issue Addressed
Users are experiencing `Status'd peer not found` errors
## Proposed Changes
Although I cannot reproduce this error, this is only one connection state change that is not addressed in the peer manager (that I could see). The error occurs because the number of disconnected peers in the peerdb becomes out of sync with the actual number of disconnected peers. From what I can tell almost all possible connection state changes are handled, except for the case when a disconnected peer changes to be disconnecting. This can potentially happen at the peer connection limit, where a previously connected peer switches to disconnecting.
This PR decrements the disconnected counter when this event occurs and from what I can tell, covers all possible disconnection state changes in the peer manager.
We were batch removing chains when purging, and then updating the status of the collection for each of those. This makes the range status be out of sync with the real status. This represented no harm to the global sync status, but I've changed it to comply with a correct debug assertion that I got triggered while doing some testing.
Also added tests and improved code quality as per @paulhauner 's suggestions.
## Issue Addressed
N/A
## Proposed Changes
1. Don't disconnect peer from dht on connection limit errors
2. Bump up `PRIORITY_PEER_EXCESS` to allow for dialing upto 60 peers by default.
Co-authored-by: Diva M <divma@protonmail.com>
## Proposed Changes
Switch over to the latest published versions of the crates in the SSZ/`tree_hash` family.
## Additional Info
The crates were published at the current head of `unstable`: 0b319d4926. All 5 crates listed in this PR were published via tags, e.g. https://github.com/sigp/lighthouse/releases/tag/tree-hash-v0.4.0
I had this change but it seems to have been lost in chaos of network upgrades.
The swarm dialing event seems to miss some cases where we dial via the behaviour. This causes an error to be logged as the peer manager doesn't know about some dialing events.
This shifts the logic to the behaviour to inform the peer manager.
## Issue Addressed
Part of a bigger effort to make the network globals read only. This moves all writes to the `PeerDB` to the `eth2_libp2p` crate. Limiting writes to the peer manager is a slightly more complicated issue for a next PR, to keep things reviewable.
## Proposed Changes
- Make the peers field in the globals a private field.
- Allow mutable access to the peers field to `eth2_libp2p` for now.
- Add a new network message to update the sync state.
Co-authored-by: Age Manning <Age@AgeManning.com>
## Issue Addressed
Running a beacon node I triggered a sync debug panic. And so finally the time to create tests for sync arrived. Fortunately, te bug was not in the sync algorithm itself but a wrong assertion
## Proposed Changes
- Split Range's impl from the BeaconChain via a trait. This is needed for testing. The TestingRig/Harness is way bigger than needed and does not provide the modification functionalities that are needed to test sync. I find this simpler, tho some could disagree.
- Add a regression test for sync that fails before the changes.
- Fix the wrong assertion.
RPC Responses are for some reason not removing their timeout when they are completing.
As an example:
```
Nov 09 01:18:20.256 DEBG Received BlocksByRange Request step: 1, start_slot: 728465, count: 64, peer_id: 16Uiu2HAmEmBURejquBUMgKAqxViNoPnSptTWLA2CfgSPnnKENBNw
Nov 09 01:18:20.263 DEBG Received BlocksByRange Request step: 1, start_slot: 728593, count: 64, peer_id: 16Uiu2HAmEmBURejquBUMgKAqxViNoPnSptTWLA2CfgSPnnKENBNw
Nov 09 01:18:20.483 DEBG BlocksByRange Response sent returned: 63, requested: 64, current_slot: 2466389, start_slot: 728465, msg: Failed to return all requested blocks, peer: 16Uiu2HAmEmBURejquBUMgKAqxViNoPnSptTWLA2CfgSPnnKENBNw
Nov 09 01:18:20.500 DEBG BlocksByRange Response sent returned: 64, requested: 64, current_slot: 2466389, start_slot: 728593, peer: 16Uiu2HAmEmBURejquBUMgKAqxViNoPnSptTWLA2CfgSPnnKENBNw
Nov 09 01:18:21.068 DEBG Received BlocksByRange Request step: 1, start_slot: 728529, count: 64, peer_id: 16Uiu2HAmEmBURejquBUMgKAqxViNoPnSptTWLA2CfgSPnnKENBNw
Nov 09 01:18:21.272 DEBG BlocksByRange Response sent returned: 63, requested: 64, current_slot: 2466389, start_slot: 728529, msg: Failed to return all requested blocks, peer: 16Uiu2HAmEmBURejquBUMgKAqxViNoPnSptTWLA2CfgSPnnKENBNw
Nov 09 01:18:23.434 DEBG Received BlocksByRange Request step: 1, start_slot: 728657, count: 64, peer_id: 16Uiu2HAmEmBURejquBUMgKAqxViNoPnSptTWLA2CfgSPnnKENBNw
Nov 09 01:18:23.665 DEBG BlocksByRange Response sent returned: 64, requested: 64, current_slot: 2466390, start_slot: 728657, peer: 16Uiu2HAmEmBURejquBUMgKAqxViNoPnSptTWLA2CfgSPnnKENBNw
Nov 09 01:18:25.851 DEBG Received BlocksByRange Request step: 1, start_slot: 728337, count: 64, peer_id: 16Uiu2HAmEmBURejquBUMgKAqxViNoPnSptTWLA2CfgSPnnKENBNw
Nov 09 01:18:25.851 DEBG Received BlocksByRange Request step: 1, start_slot: 728401, count: 64, peer_id: 16Uiu2HAmEmBURejquBUMgKAqxViNoPnSptTWLA2CfgSPnnKENBNw
Nov 09 01:18:26.094 DEBG BlocksByRange Response sent returned: 62, requested: 64, current_slot: 2466390, start_slot: 728401, msg: Failed to return all requested blocks, peer: 16Uiu2HAmEmBURejquBUMgKAqxViNoPnSptTWLA2CfgSPnnKENBNw
Nov 09 01:18:26.100 DEBG BlocksByRange Response sent returned: 63, requested: 64, current_slot: 2466390, start_slot: 728337, msg: Failed to return all requested blocks, peer: 16Uiu2HAmEmBURejquBUMgKAqxViNoPnSptTWLA2CfgSPnnKENBNw
Nov 09 01:18:31.070 DEBG RPC Error direction: Incoming, score: 0, peer_id: 16Uiu2HAmEmBURejquBUMgKAqxViNoPnSptTWLA2CfgSPnnKENBNw, client: Prysm: version: a80b1c252a9b4773493b41999769bf3134ac373f, os_version: unknown, err: Stream Timeout, protocol: beacon_blocks_by_range, service: libp2p
Nov 09 01:18:31.070 WARN Timed out to a peer's request. Likely insufficient resources, reduce peer count, service: libp2p
Nov 09 01:18:31.085 DEBG RPC Error direction: Incoming, score: 0, peer_id: 16Uiu2HAmEmBURejquBUMgKAqxViNoPnSptTWLA2CfgSPnnKENBNw, client: Prysm: version: a80b1c252a9b4773493b41999769bf3134ac373f, os_version: unknown, err: Stream Timeout, protocol: beacon_blocks_by_range, service: libp2p
Nov 09 01:18:31.085 WARN Timed out to a peer's request. Likely insufficient resources, reduce peer count, service: libp2p
Nov 09 01:18:31.459 DEBG RPC Error direction: Incoming, score: 0, peer_id: 16Uiu2HAmEmBURejquBUMgKAqxViNoPnSptTWLA2CfgSPnnKENBNw, client: Prysm: version: a80b1c252a9b4773493b41999769bf3134ac373f, os_version: unknown, err: Stream Timeout, protocol: beacon_blocks_by_range, service: libp2p
Nov 09 01:18:31.459 WARN Timed out to a peer's request. Likely insufficient resources, reduce peer count, service: libp2p
Nov 09 01:18:34.129 DEBG RPC Error direction: Incoming, score: 0, peer_id: 16Uiu2HAmEmBURejquBUMgKAqxViNoPnSptTWLA2CfgSPnnKENBNw, client: Prysm: version: a80b1c252a9b4773493b41999769bf3134ac373f, os_version: unknown, err: Stream Timeout, protocol: beacon_blocks_by_range, service: libp2p
Nov 09 01:18:34.130 WARN Timed out to a peer's request. Likely insufficient resources, reduce peer count, service: libp2p
Nov 09 01:18:35.686 DEBG Peer Manager disconnecting peer reason: Too many peers, peer_id: 16Uiu2HAmEmBURejquBUMgKAqxViNoPnSptTWLA2CfgSPnnKENBNw, service: libp2p
```
This PR is to investigate and correct the issue.
~~My current thoughts are that for some reason we are not closing the streams correctly, or fast enough, or the executor is not registering the closes and waking up.~~ - Pretty sure this is not the case, see message below for a more accurate reason.
~~I've currently added a timeout to stream closures in an attempt to force streams to close and the future to always complete.~~ I removed this
## Issue Addressed
Resolves#2775
## Proposed Changes
1. Reduces the target_peers to stop recursive discovery requests.
2. Changes the eth1 `auto_update_interval` config parameter to be equal to the eth1 block time in the simulator. Without this, the eth1 `latest_cached_block` wouldn't be updated for some slots around `eth1_voting_period` boundaries which would lead to the eth1 cache falling out of sync. This is what caused the `Syncing eth1 block cache` and `No valid eth1_data votes` logs.
## Issue Addressed
N/A
## Proposed Changes
From discord, it seems like users are a bit unclear on how to run checkpoint sync if they don't have an existing synced beacon node. Adds a note on how to use infura for the checkpoint sync feature.
## Issue Addressed
Resolves#2545
## Proposed Changes
Adds the long-overdue EF tests for fork choice. Although we had pretty good coverage via other implementations that closely followed our approach, it is nonetheless important for us to implement these tests too.
During testing I found that we were using a hard-coded `SAFE_SLOTS_TO_UPDATE_JUSTIFIED` value rather than one from the `ChainSpec`. This caused a failure during a minimal preset test. This doesn't represent a risk to mainnet or testnets, since the hard-coded value matched the mainnet preset.
## Failing Cases
There is one failing case which is presently marked as `SkippedKnownFailure`:
```
case 4 ("new_finalized_slot_is_justified_checkpoint_ancestor") from /home/paul/development/lighthouse/testing/ef_tests/consensus-spec-tests/tests/minimal/phase0/fork_choice/on_block/pyspec_tests/new_finalized_slot_is_justified_checkpoint_ancestor failed with NotEqual:
head check failed: Got Head { slot: Slot(40), root: 0x9183dbaed4191a862bd307d476e687277fc08469fc38618699863333487703e7 } | Expected Head { slot: Slot(24), root: 0x105b49b51bf7103c182aa58860b039550a89c05a4675992e2af703bd02c84570 }
```
This failure is due to #2741. It's not a particularly high priority issue at the moment, so we fix it after merging this PR.
## Issue Addressed
Resolves#2602
## Proposed Changes
*Note: For a review it might help to look at the individual commits.*
### `boot_node`
Add support for the flags `dump-config` and `immediate-shutdown`. For `immediate-shutdown` the actual behavior could be described as `dump-config-and-exit`.
Both flags are handled in `boot_node::main`, which appears to be the simplest approach.
### `boot_node` regression tests
Added in `lighthouse/tests/boot_node.rs`.
### `CommandLineTestExec`
Factors out boilerplate related to CLI tests. It's used in the regression tests for `boot_node`, `beacon_node` and `validator_client`.
## Open TODO
Add tests for `boot_node` flags `enable-enr-auto-update` and `disable-packet-filter`. They end up in [`Discv5Config`](9ed2cba6bc/boot_node/src/config.rs (L29)), which doesn't support serde (de)serialization.
I haven't found a workaround - guidance would be appreciated.
This simply moves some functions that were "swarm notifications" to a network behaviour implementation.
Notes
------
- We could disconnect from the peer manager but we would lose the rpc shutdown message
- We still notify from the swarm since this is the most reliable way to get some events. Ugly but best for now
- Events need to be pushed with "add event" to wake the waker
Co-authored-by: Divma <26765164+divagant-martian@users.noreply.github.com>
## Issue Addressed
Closes https://github.com/sigp/lighthouse/issues/2112
Closes https://github.com/sigp/lighthouse/issues/1861
## Proposed Changes
Collect attestations by validator index in the slasher, and use the magic of reference counting to automatically discard redundant attestations. This results in us storing only 1-2% of the attestations observed when subscribed to all subnets, which carries over to a 50-100x reduction in data stored 🎉
## Additional Info
There's some nuance to the configuration of the `slot-offset`. It has a profound effect on the effictiveness of de-duplication, see the docs added to the book for an explanation: 5442e695e5/book/src/slasher.md (slot-offset)
## Issue Addressed
No specific issue. Just some improvement in the documentation provided by the book.
## Proposed Changes
Add minimum supported version for checkpoint sync in book to make sure users who want to use this feature know they need to be using at least version 2.0.0.
## Issue Addressed
This is related to #1926 and #1712.
## Proposed Changes
This PR adds a test that make sure that the used dependencies can be vendored.
Being able to vendor the dependencies is important for archival and repdroducibility purpose.
It's also required to package lighthouse for some Linux distributions. Specifically [NixOS](https://nixos.org/) and [Yocto](https://www.yoctoproject.org/).
## Additional Info
This PR only adds the test, it doesn't clean up the dependencies yet. That's why it is in draft.
## Issue Addressed
I've done this change in a couple of WIPs already so I might as well submit it on its own. This changes no functionality but reduces coupling in a 0.0001%. It also helps new people who need to work in the peer manager to better understand what it actually needs from the outside
## Proposed Changes
Add a config to the peer manager
## Issue Addressed
The computation of metrics in the network service can be expensive. This disables the computation unless the cli flag `metrics` is set.
## Additional Info
Metrics in other parts of the network are still updated, since most are simple metrics and checking if metrics are enabled each time each metric is updated doesn't seem like a gain.
## Issue Addressed
@paulhauner noticed that when we send head events, we use the block root from `new_head` in `fork_choice_internal`, but calculate `dependent_root` and `previous_dependent_root` using the `canonical_head`. This is normally fine because `new_head` updates the `canonical_head` in `fork_choice_internal`, but it's possible we have a reorg updating `canonical_head` before our head events are sent. So this PR ensures `dependent_root` and `previous_dependent_root` are always derived from the state associated with `new_head`.
Co-authored-by: realbigsean <seananderson33@gmail.com>
While testing some code on Windows, I ran into a failure when using `clippy` via (`make lint`):
```
error: this expression borrows a reference (`&str`) that is immediately dereferenced by the compiler
--> common/filesystem/src/lib.rs:105:43
|
105 | let mut acl = ACL::from_file_path(&path_str, false).map_err(Error::UnableToRetrieveACL)?;
| ^^^^^^^^^ help: change this to: `path_str`
|
= note: `-D clippy::needless-borrow` implied by `-D warnings`
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
error: could not compile `filesystem` due to previous error
```
## Proposed Changes
Remove the unnecessary borrow as suggested.
## Additional Info
Since we are only running `clippy` in CI on Ubuntu, I believe we don't have any way (in CI) to detect these Windows specific lint errors (either from new code, or from linting changes from new Rust versions.
This is because code marked as `#[cfg(windows)]` is not checked on `unix` systems and vice versa.
I'm conscious that our CI runs are already taking a long time, and that adding a new Windows `clippy` run would add a non-negligible amount of time to the runs (not sure if this topic has already been discussed), but it something to be aware of.
## Extra Note
I don't think this is the case, but it might be worth someone else running `make lint` on their Windows machines to eliminate the possibility that this is an error specific to my setup.
## Issue Addressed
Resolves#2612
## Proposed Changes
Implements both the checks mentioned in the original issue.
1. Verifies the `randao_reveal` in the beacon node
2. Cross checks the proposer index after getting back the block from the beacon node.
## Additional info
The block production time increases by ~10x because of the signature verification on the beacon node (based on the `beacon_block_production_process_seconds` metric) when running on a local testnet.
## Proposed Changes
Add several metrics for the number of attestations in the op pool. These give us a way to observe the number of valid, non-trivial attestations during block packing rather than just the size of the entire op pool.
## Issue Addressed
Getting too many peers kicked due to slightly late sync committee messages as tested on.. under-performant hardware.
## Proposed Changes
Only penalize if the message is more than one slot late. Still ignore the message-
Co-authored-by: Divma <26765164+divagant-martian@users.noreply.github.com>
This is a pre-cursor to the next libp2p upgrade.
It is currently being used for staging a number of PR upgrades which are contingent on the latest libp2p.
## Issue Addressed
The [p2p-interface section of the `altair` spec](https://github.com/ethereum/consensus-specs/blob/dev/specs/altair/p2p-interface.md#transitioning-the-gossip) says you should subscribe to the topics for a fork "In advance of the fork" and unsubscribe from old topics `2 Epochs` after the new fork is activated. We've chosen to subscribe to new fork topics `2 slots` before the fork is initiated.
This function is supposed to return the required fork digests at any given time but as it was currently written, it doesn't return the fork digest for a previous fork if you've switched to the current fork less than 2 epoch's ago. Also this function required modification for every new fork we add.
## Proposed Changes
Make this function fork-agnostic and correctly handle the previous fork topic digests when you've only just switched to the new fork.
## Issue Addressed
Resolves#2611
## Proposed Changes
Adds a duplicate block root cache to the `BeaconProcessor`. Adds the block root to the cache before calling `process_gossip_block` and `process_rpc_block`. Since `process_rpc_block` is called only for single block lookups, we don't have to worry about batched block imports.
The block is imported from the source(gossip/rpc) that arrives first. The block that arrives second is not imported to avoid the db access issue.
There are 2 cases:
1. Block that arrives second is from rpc: In this case, we return an optimistic `BlockError::BlockIsAlreadyKnown` to sync.
2. Block that arrives second is from gossip: In this case, we only do gossip verification and forwarding but don't import the block into the the beacon chain.
## Additional info
Splits up `process_gossip_block` function to `process_gossip_unverified_block` and `process_gossip_verified_block`.
## Proposed Changes
* Add the `Eth-Consensus-Version` header to the HTTP API for the block and state endpoints. This is part of the v2.1.0 API that was recently released: https://github.com/ethereum/beacon-APIs/pull/170
* Add tests for the above. I refactored the `eth2` crate's helper functions to make this more straight-forward, and introduced some new mixin traits that I think greatly improve readability and flexibility.
* Add a new `map_with_fork!` macro which is useful for decoding a superstruct type without naming all its variants. It is now used for SSZ-decoding `BeaconBlock` and `BeaconState`, and for JSON-decoding `SignedBeaconBlock` in the API.
## Additional Info
The `map_with_fork!` changes will conflict with the Merge changes, but when resolving the conflict the changes from this branch should be preferred (it is no longer necessary to enumerate every fork). The merge fork _will_ need to be added to `map_fork_name_with`.
## Issue Addressed
Currently, if you launch the beacon node with the `--purge-db` flag and the `beacon` directory exists, but one (or both) of the `chain_db` or `freezer-db` directories are missing, it will error unnecessarily with:
```
Failed to remove chain_db: No such file or directory (os error 2)
```
This is an edge case which can occur in cases of manual intervention (a user deleted the directory) or if you had previously run with the `--purge-db` flag and Lighthouse errored before it could initialize the db directories.
## Proposed Changes
Check if the `chain_db`/`freezer_db` exists before attempting to remove them. This prevents unnecessary errors.
## Issue Addressed
Currently, running the Web3Signer tests locally without having a java runtime environment installed and available on your PATH will result in the tests failing.
## Proposed Changes
Add a note regarding the Web3Signer tests being dependent on java (similar to what we have for `ganache-cli`)
I have been in the process of debugging libp2p tasks as there is something locking our executor.
This addition adds a metric allowing us to track all tasks within lighthouse allowing us to identify various sections of Lighthouse code that may be taking longer than normal to process.
## Issue Addressed
Continuation of #2728, fix the fork choice tests for Rust 1.56.0 so that `unstable` is free of warnings.
CI will be broken until this PR merges, because we strictly enforce the absence of warnings (even for tests)
## Issue Addressed
Attempts to fix#2701 but I doubt this is the reason behind that.
## Proposed Changes
maintain a waker in the rpc handler and call it if an event is received
## Issue Addressed
e895074ba updated the altair fork and now that we are a week away this test no longer panics.
## Proposed Changes
Remove the expected panic and explanatory note.
## Issue Addressed
In the backfill sync the state was maintained twice, once locally and also in the globals. This makes it so that it's maintained only once.
The only behavioral change is that when backfill sync in paused, the global backfill state is updated. I asked @AgeManning about this and he deemed it a bug, so this solves it.
## Issue Addressed
When compiling with Rust 1.56.0 the compiler generates 3 instances of this warning:
```
warning: trailing semicolon in macro used in expression position
--> common/eth2_network_config/src/lib.rs:181:24
|
181 | })?;
| ^
...
195 | let deposit_contract_deploy_block = load_from_file!(DEPLOY_BLOCK_FILE);
| ---------------------------------- in this macro invocation
|
= note: `#[warn(semicolon_in_expressions_from_macros)]` on by default
= warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
= note: for more information, see issue #79813 <https://github.com/rust-lang/rust/issues/79813>
= note: this warning originates in the macro `load_from_file` (in Nightly builds, run with -Z macro-backtrace for more info)
```
This warning is completely harmless, but will be visible to users compiling Lighthouse v2.0.1 (or earlier) with Rust 1.56.0 (to be released October 21st). It is **completely safe** to ignore this warning, it's just a superficial change to Rust's syntax.
## Proposed Changes
This PR removes the semi-colon as recommended, and fixes the new Clippy lints from 1.56.0
## Issue Addressed
Mitigates #1096
## Proposed Changes
Add a flag to the beacon node called `--disable-lock-timeouts` which allows opting out of lock timeouts.
The lock timeouts serve a dual purpose:
1. They prevent any single operation from hogging the lock for too long. When a timeout occurs it logs a nasty error which indicates that there's suboptimal lock use occurring, which we can then act on.
2. They allow deadlock detection. We're fairly sure there are no deadlocks left in Lighthouse anymore but the timeout locks offer a safeguard against that.
However, timeouts on locks are not without downsides:
They allow for the possibility of livelock, particularly on slower hardware. If lock timeouts keep failing spuriously the node can be prevented from making any progress, even if it would be able to make progress slowly without the timeout. One particularly concerning scenario which could occur would be if a DoS attack succeeded in slowing block signature verification times across the network, and all Lighthouse nodes got livelocked because they timed out repeatedly. This could also occur on just a subset of nodes (e.g. dual core VPSs or Raspberri Pis).
By making the behaviour runtime configurable this PR allows us to choose the behaviour we want depending on circumstance. I suspect that long term we could make the timeout-free approach the default (#2381 moves in this direction) and just enable the timeouts on our testnet nodes for debugging purposes. This PR conservatively leaves the default as-is so we can gain some more experience before switching the default.
