This is a little bit of a tip-of-the-iceberg PR. It houses a lot of code changes in the libp2p dependency.
This needs a bit of thorough testing before merging.
The primary code changes are:
- General libp2p dependency update
- Gossipsub refactor to shift compression into gossipsub providing performance improvements and improved API for handling compression
Co-authored-by: Paul Hauner <paul@paulhauner.com>
## Issue Addressed
NA
## Proposed Changes
This was mostly done to find the reason why LH was dropping peers from Nimbus. It proved to be useful so I think it's worth it. But there is also some functional stuff here
- Add metrics for rpc errors per client, error type and direction
- Add metrics for downscoring events per source type, client and penalty type
- Add metrics for gossip validation results per client for non-accepted messages
- Make the RPC handler return errors and requests/responses in the order we see them
- Allow a small burst for the Ping rate limit, from 1 every 5 seconds to 2 every 10 seconds
- Send rate limiting errors with a particular code and use that same code to identify them. I picked something different to 128 since that is most likely what other clients are using for their own errors
- Remove some unused code in the `PeerAction` and the rpc handler
- Remove the unused variant `RateLimited`. tTis was never produced directly, since the only way to get the request's protocol is via de handler. The handler upon receiving from LH a response with an error (rate limited in this case) emits this event with the missing info (It was always like this, just pointing out that we do downscore rate limiting errors regardless of the change)
Metrics for Nimbus looked like this:
Downscoring events: `increase(libp2p_peer_actions_per_client{client="Nimbus"}[5m])`

RPC Errors: `increase(libp2p_rpc_errors_per_client{client="Nimbus"}[5m])`

Unaccepted gossip message: `increase(gossipsub_unaccepted_messages_per_client{client="Nimbus"}[5m])`

## Issue Addressed
Following slog's documentation, this should help a bit with string allocations. I left it run for two days and mem usage is lower. This is of course anecdotal, but shouldn't harm anyway
## Proposed Changes
remove `String` creation in logs when possible
## Issue Addressed
- Asymmetric pings - Currently with symmetric ping intervals, lighthouse nodes race each other to ping often ending in simultaneous ping connections. This shifts the ping interval to be asymmetric based on inbound/outbound connections
- Correct inbound/outbound peer-db registering - It appears we were accounting inbound as outbound and vice versa in the peerdb, this has been corrected
- Improved logging
There is likely more to come - I'll leave this open as we investigate further testnets
## Issue Addressed
#1825
## Proposed Changes
Since we penalize more blocks by range requests that have large steps, it is possible to get requests that will never be processed. We were not informing peers about this requests and also logging CRIT that is no longer relevant. Later we should check if more sophisticated handling for those requests is needed
## 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>
## 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
#1056
## Proposed Changes
- Add a rate limiter to the RPC behaviour. This also means the rate limiting occurs just before the door to the application level, so the number of connections a peer opens does not affect this (this would happen in the future if put on the handler)
- The algorithm used is the leaky bucket as a meter / token bucket implemented the GCRA way
- Each protocol has its own limit. Due to the way the algorithm works, the "small" protocols have a hard limit, while bbrange and bbroot allow [burstiness](https://www.wikiwand.com/en/Burstiness). This is so that a peer can't request hundreds of individual requests expecting only one block in a short period of time, it also allows a peer to send two half size requests instead of one with max if they want to without getting limited, and.. it also allows a peer to request a batch of the maximum size and then send _appropriately spaced_ requests of really small sizes. From what I've seen in sync this is plausible when reaching the target slot.
## Additional Info
Needs to be heavily tested