Add peer handling diagram. #39
Conversation
| │ ┌────────────┐ are requests │ | ||
| │ │ Framed │ │ | ||
| │ │ Messages │─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─│─ ─ ─ | ||
| │ └────────────┘ last-seen timestamp channel │ │ |
There was a problem hiding this comment.
a hook on the receiving end of the framed stream can fire a (SocketAddr, DateTime<Utc>) pair into an async mpsc channel before continuing to process the message.
| │ │ │ | ||
| ┌───────────┼────────────────────────┼──────────┐ | ||
| │ │ PeerSet: two Services │ │ │ | ||
| │ │ plus bookkeeping ▼ │ |
There was a problem hiding this comment.
The PeerSet maintains a pool of connected peers and is responsible for dynamically determining the peerset size.
The PeerSet contains a client and server Service`.
The server Service collects requests from all connected peers and routes them / load balances across internal services. Its poll_ready implementation should use backpressure information from all the inbound requests it sees to determine when the backing services are overloaded by the external network, and if so, drop a request, causing the PeerServer to terminate the connection, contracting the peerset (and reducing load).
The client Service collects requests from internal services and load balances them across available peer connections. Its poll_ready implementation should use backpressure information from outbound requests it sees to determine when additional peers are needed to handle outgoing requests (e.g., attempting to download many blocks at once), and then asynchronously construct new peers via the PeerConnector service. It should probably also have a slight bias towards expanding the peerset size, so that we have a "full" set of peers by default.
| └───────────────────▶│ rsp: Vec<MetaAddr> │ | ||
| │ │ | ||
| │ truncates timestamps │ | ||
| └─────────────────────────────┘ |
There was a problem hiding this comment.
Here is an example of only one internal service, an AddressGossip service used to respond to getaddr requests, which pulls the (authenticated) last-seen info from the AddressBook and truncates timestamps.
|
|
|
For the "PeerSet", I think we probably want to study the |
This has the export of something I sketched in Monodraw; I'd like to upload the original Monodraw file but I'm not sure if other people also use it and what information it embeds in the binary.