Improve P2PStream buffering

[mattsse]

Describe the feature

we currently have a buffer:

reth/crates/net/eth-wire/src/p2pstream.rs

Lines 244 to 245 in ff9a42a

	/// Outgoing messages buffered for sending to the underlying stream.
	outgoing_messages: VecDeque<Bytes>,

TODO

• remove buffer
• update how pings are processed, because if we now go through the Sink API, then this must be stored as options that we optionally need to keep around
• if we modify the poll logic in p2pstream then we also need to manually add a flush call at the callsite

  reth/crates/net/network/src/session/active.rs

  Line 569 in ff9a42a

  }

also ptal at the Sink docs if unfamiliar with the Sink API

Additional context

No response

[MatteoMer]

hey! Would love to work on this 🫡

[jenpaff]

hey! Would love to work on this 🫡

assigned !

[MatteoMer]

I made a draft for the issue #12417

But @mattsse I've still got few questions 😄

1. In my PR I only managed the case where there's one ping that needs to be saved (waiting to be sent). Is there any real case scenario where multiple pings would need to be saved?
   For example a ping and pong? Maybe it should be an array of saved pings?

2. It was not described in the PR description, but I also needed to handle disconnect, but unfortunately, I don't think I managed to do it 1/1 to the original version.
   Since we don't have access to the buffer anymore, we cannot clear the messages that are waiting to be sent. Maybe it's already handled by the inner Sink?
   Right now I'm just sending a disconnect message, and in poll_flush, treating it as a priority.
   But let me know what's the best way 🫡

[mattsse]

In my PR I only managed the case where there's one ping that needs to be saved (waiting to be sent). Is there any real case scenario where multiple pings would need to be saved?

we can ignore this case and only consider one pending ping/pong at a time

Right now I'm just sending a disconnect message, and in poll_flush, treating it as a priority.

that makes sense and fits how flush is supposed to work

[github-actions]

This issue is stale because it has been open for 21 days with no activity.