aquatic/TODO.md

TODO

• readme

  • document privilege dropping and cpu pinning

• config

  • add flag to print parsed config when starting
  • fail on unrecognized keys

• quit whole program if any thread panics

• implement socket_recv_size and ipv6_only in glommio implementations

• CI

  • file transfer CI for all implementations
  • test access lists?
  • cargo-deny

• aquatic_udp

  • look at proper cpu pinning (check that one thread gets bound per core)
    • then consider so_attach_reuseport_cbpf
  • what poll event capacity is actually needed?
  • stagger connection cleaning intervals?
  • load test
    • move additional request sending to for each received response, maybe with probability 0.2

• aquatic_http:

  • clean out connections regularly
    • Rc<RefCell> which get set on successful request parsing and successful response sending. Clone kept in connection slab which gets cleaned periodically (= cancel tasks). Means that task handle will need to be stored in slab. Config vars kill_idle_connections: bool, max_idle_connection_time. Remove keepalive.
    • handle panicked/cancelled tasks?
  • optimize?
    • get_peer_addr only once (takes 1.2% of runtime)
    • queue response: allocating takes 2.8% of runtime
  • use futures-rustls for load test
  • consider better error type for request parsing, so that better error messages can be sent back (e.g., "full scrapes are not supported")

• aquatic_ws

  • glommio
    • proper cpu set pinning
    • RES memory still high after traffic stops, even if torrent maps and connection slabs go down to 0 len and capacity
      • replacing indexmap_amortized / simd_json with equivalents doesn't help
    • SinkExt::send maybe doesn't wake up properly?
      • related to https://github.com/sdroege/async-tungstenite/blob/master/src/compat.rs#L18 ?
  • general
    • large amount of temporary allocations in serialize_20_bytes, pretty many in deserialize_20_bytes

Less important

• extract response peers: extract "one extra" to compensate for removal, of sender if present in selection? maybe make criterion benchmark, optimize

aquatic_http_load_test

• how handle large number of peers for "popular" torrents in keepalive mode? maybe it is ok

aquatic_http

• test torrent transfer with real clients
  • scrape: does it work (serialization etc), and with multiple hashes?
  • 'left' optional in magnet requests? Probably not. Transmission sends huge positive number.
• compact=0 should result in error response

aquatic_ws_load_test

• very small amount of connections means very small number of peers per torrents, so tracker handling of large number is not really assessed

Not important

aquatic_ws

• write new version of extract_response_peers which checks for equality with peer sending request? It could return an arrayvec or smallvec by the way (but then the size needs to be adjusted together with the corresponding config var, or the config var needs to be removed)

aquatic_cli_helpers

• Include config field comments in exported toml (likely quite a bit of work)

Don't do

• general: PGO didn't seem to help way back

aquatic_http

• request from path:
  • deserialize 20 bytes: possibly rewrite (just check length of underlying bytes == 20 and then copy them), also maybe remove String from map for these cases too. doesn't really improve performance
  • crazy http parsing: check for newline with memchr, take slice until there. then iter over space newlines/just take relevant data. Not faster than httparse and a lot worse

aquatic_udp_protocol

• Use bytes crate: seems to worsen performance somewhat
• Zerocopy (https://docs.rs/zerocopy/0.3.0/zerocopy/index.html) for requests and responses. Doesn't improve performance