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punktfunk/crates/punktfunk-core/Cargo.toml
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enricobuehler c24b571e37
ci / rust (push) Has been cancelled
feat(1gbps): batched send via sendmmsg (Transport::send_batch)
First increment of the 1 Gbps send-path rework (the measured bottleneck): the
native data plane did one send() syscall per packet — at ~125k pkt/s (1 Gbps
wire) that burns a core on syscalls. Port the proven GameStream sendmmsg path
into the core Transport seam.

- Transport gains `send_batch(&[&[u8]]) -> usize` (count handed to the kernel;
  caller counts the rest as send-buffer drops). Default = the scalar send loop
  (loopback transport + non-Linux).
- UdpTransport overrides it on Linux with `sendmmsg` (64 datagrams/syscall);
  the connected socket needs no per-message address. Non-blocking-aware: a full
  send buffer yields a short count / EAGAIN, and we stop + report what went out
  rather than block or retry (same lossy, FEC-protected contract as send()).
- Session::submit_frame seals every shard then hands the whole frame to
  send_batch in ONE call instead of looping send() — ~64x fewer syscalls per
  frame on the native + GameStream-over-core paths; send_dropped accounting
  preserved (total - sent).

~125k → ~2k syscalls/sec at 1 Gbps line rate. Verified: new loopback-UDP test
send_batch_delivers_over_loopback (100 batched packets arrive intact, datagram
boundaries preserved); full core suite + clippy + fmt green.

Next increments: a paced send thread (microburst shaping so a real NIC doesn't
drop line-rate bursts) and recvmmsg on the client.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-11 21:55:22 +00:00

59 lines
2.6 KiB
TOML

[package]
name = "punktfunk-core"
description = "punktfunk shared protocol/transport/FEC core, exposed over a stable C ABI"
version.workspace = true
edition.workspace = true
rust-version.workspace = true
license.workspace = true
authors.workspace = true
repository.workspace = true
[lib]
name = "punktfunk_core"
# `lib` — so punktfunk-host / punktfunk-client-rs / tools link it as a normal Rust crate.
# `staticlib` — `libpunktfunk_core.a` for the C test harness and static embedding.
# `cdylib` — `libpunktfunk_core.{so,dylib}` for Swift/Kotlin clients via the C ABI.
crate-type = ["lib", "cdylib", "staticlib"]
[features]
default = []
# Control-plane QUIC (pairing, config, reverse audio). tokio is permitted ONLY here,
# never on the per-frame hot path. Off by default so the core stays runtime-free.
quic = ["dep:quinn", "dep:tokio", "dep:rustls", "dep:rcgen", "dep:rustls-pki-types", "dep:sha2", "dep:hmac", "dep:spake2"]
[dependencies]
reed-solomon-simd = "3.1" # GF(2^16) Leopard-RS, SIMD, O(n log n) — the wall-breaker (P2)
# Vendored fork of fec-rs: GF(2^8) classic RS with the *Cauchy* generator matrix
# (M[j][i] = inv[(m+i)^j]) — byte-identical to the `nanors` library Moonlight uses, so our
# parity is decodable by a stock Moonlight client. (reed-solomon-erasure is Vandermonde and is
# NOT interoperable.) See vendor/fec-rs/LICENSE (BSD-2-Clause).
fec-rs = { path = "vendor/fec-rs" }
aes-gcm = "0.10" # AES-128-GCM session crypto, matches GameStream
zerocopy = { version = "0.8", features = ["derive"] }
bytes = "1"
socket2 = "0.6" # set SO_SNDBUF/SO_RCVBUF — default UDP buffers are too small for 4K/5K frame bursts
thiserror = "2"
tracing = { version = "0.1", default-features = false, features = ["std"] }
rand = "0.9"
zeroize = "1"
quinn = { version = "0.11", optional = true }
rustls = { version = "0.23", optional = true, default-features = false, features = ["ring", "std"] }
rcgen = { version = "0.13", optional = true, default-features = false, features = ["aws_lc_rs", "pem"] }
rustls-pki-types = { version = "1", optional = true }
sha2 = { version = "0.10", optional = true }
hmac = { version = "0.12", optional = true }
spake2 = { version = "0.4", optional = true }
tokio = { version = "1", optional = true, features = ["rt-multi-thread", "net", "sync", "macros"] }
# `sendmmsg` batched UDP send (the 1 Gbps+ syscall lever) — Linux only; other targets use the
# scalar `send` loop fallback.
[target.'cfg(target_os = "linux")'.dependencies]
libc = "0.2"
[dev-dependencies]
proptest = "1"
[build-dependencies]
cbindgen = "0.29"