Class: Raindrops::TCP_Info

Inherits:
Object
  • Object
show all
Defined in:
ext/raindrops/tcp_info.c,
ext/raindrops/tcp_info.c

Overview

This is used to wrap "struct tcp_info" as described in tcp(7) and /usr/include/linux/tcp.h. The following readers methods are defined corresponding to the "tcpi_" fields in the tcp_info struct.

As of raindrops 0.18.0+, this is supported on FreeBSD and OpenBSD systems as well as Linux, although not all fields exist or match the documentation, below.

In particular, the last_data_recv field is useful for measuring the amount of time a client spent in the listen queue before accept(), but only if TCP_DEFER_ACCEPT is used with the listen socket (it is on by default in Unicorn).

  • state
  • ca_state
  • retransmits
  • probes
  • backoff
  • options
  • snd_wscale
  • rcv_wscale
  • rto
  • ato
  • snd_mss
  • rcv_mss
  • unacked
  • sacked
  • lost
  • retrans
  • fackets
  • last_data_sent
  • last_ack_sent
  • last_data_recv
  • last_ack_recv
  • pmtu
  • rcv_ssthresh
  • rtt
  • rttvar
  • snd_ssthresh
  • snd_cwnd
  • advmss
  • reordering
  • rcv_rtt
  • rcv_space
  • total_retrans

https://kernel.org/doc/man-pages/online/pages/man7/tcp.7.html

Instance Method Summary collapse

Instance Method Details

#get!(io) ⇒ Object

Raindrops::TCP_Info.new(tcp_socket) -> TCP_Info object

Reads a TCP_Info object from any given tcp_socket. See the tcp(7) manpage and /usr/include/linux/tcp.h for more details.



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# File 'ext/raindrops/tcp_info.c', line 77

static VALUE init(VALUE self, VALUE io)
{
	int fd = my_fileno(io);
	struct tcp_info *info = DATA_PTR(self);
	socklen_t len = (socklen_t)sizeof(struct tcp_info);
	int rc = getsockopt(fd, IPPROTO_TCP, TCP_INFO, info, &len);

	if (rc != 0)
		rb_sys_fail("getsockopt");

	return self;
}