We're happy for the kernel to batch update and gossip messages, but a * commitment message, for example, should be instantly sent. There's no * great way of doing this, unfortunately. * * Setting TCP_NODELAY on Linux flushes the socket, which really means * we'd want to toggle on then off it *after* sending. But Linux has * TCP_CORK. On FreeBSD, it seems (looking at source) not to, so *
| 312 | * only means one extra packet. |
| 313 | */ |
| 314 | static void set_urgent_flag(struct peer *peer, bool urgent) |
| 315 | { |
| 316 | int val; |
| 317 | int opt; |
| 318 | const char *optname; |
| 319 | static bool complained = false; |
| 320 | |
| 321 | if (urgent == peer->urgent) |
| 322 | return; |
| 323 | |
| 324 | #ifdef TCP_CORK |
| 325 | opt = TCP_CORK; |
| 326 | optname = "TCP_CORK"; |
| 327 | #elif defined(TCP_NODELAY) |
| 328 | opt = TCP_NODELAY; |
| 329 | optname = "TCP_NODELAY"; |
| 330 | #else |
| 331 | #error "Please report platform with neither TCP_CORK nor TCP_NODELAY?" |
| 332 | #endif |
| 333 | |
| 334 | val = urgent; |
| 335 | if (setsockopt(io_conn_fd(peer->to_peer), |
| 336 | IPPROTO_TCP, opt, &val, sizeof(val)) != 0) { |
| 337 | /* This actually happens in testing, where we blackhole the fd */ |
| 338 | if (!complained) { |
| 339 | status_unusual("setsockopt %s=1: %s", |
| 340 | optname, |
| 341 | strerror(errno)); |
| 342 | complained = true; |
| 343 | } |
| 344 | } |
| 345 | peer->urgent = urgent; |
| 346 | } |
| 347 | |
| 348 | static bool is_urgent(enum peer_wire type) |
| 349 | { |
no test coverage detected