tcp_tput.d

   1 #!/usr/sbin/dtrace -s
   2
   3 #pragma D option quiet
   4
   5 /* from https://blogs.oracle.com/amaguire/entry/exploring_tcp_throughput_with_dtrace */
   6
   7 tcp:::receive
   8 / (args[4]->tcp_flags & (TH_SYN|TH_RST|TH_FIN)) == 0 && args[4]->tcp_dport == 548 /
   9 {
  10         @swnd[args[2]->ip_saddr] =
  11             quantize((args[4]->tcp_window)*(1 << args[3]->tcps_snd_ws));
  12
  13 }
  14
  15 tcp:::send
  16 / (args[4]->tcp_flags & (TH_SYN|TH_RST|TH_FIN)) == 0 && args[4]->tcp_sport == 548 /
  17 {
  18         @unacked[args[2]->ip_daddr] =
  19             quantize(args[3]->tcps_snxt - args[3]->tcps_suna);
  20 }
  21
  22 dtrace:::END
  23 {
  24         printf("TCP Send Window Size (bytes)\n");
  25         printf("===============================\n");
  26         printa(@swnd);
  27
  28         printf("Unackknowleged data in flight (bytes)\n");
  29         printf("===============================\n");
  30         printa(@unacked);
  31 }