[dtrace] TCP TIME_WAIT duration

gistfile1.sh

#!/bin/sh

dtrace -n '
#pragma D option quiet

BEGIN {
        printf("%4s %21s\tDURATION (secs)\n", "ZONE", "ADDR:PORT");
}

tcp:::state-change
{
        this->last_state = tcp_state_string[args[5]->tcps_state];
        this->curr_state = tcp_state_string[args[3]->tcps_state];
}

/* Upon entering the TIME_WAIT state record the current time so that a
   duration may be calculated when the socket is finally closed. */

tcp:::state-change
/this->curr_state == "state-time-wait"/
{
        this->addr = args[3]->tcps_laddr;
        this->port = args[3]->tcps_lport;
        this->zone_id = args[1]->cs_zoneid;

        waiting[this->addr, this->port] = timestamp;
        conn_zone[this->addr, this->port] = this->zone_id;
}

/* This function is called from a kernel thread that fires
   periodically so the associated zoneid, pid, and tid will not help.
   Thus the conn_zone map is used. */

fbt::tcp_time_wait_remove:entry
{

        this->addr = inet_ntop(AF_INET, &args[0]->tcp_connp->connua_v6addr.connua_laddr._S6_un._S6_u32[3]);
        this->port = htons(args[0]->tcp_connp->u_port.connu_ports.connu_lport);
        this->zone_id = conn_zone[this->addr, this->port];
        this->duration = timestamp - waiting[this->addr, this->port];

        printf("%4d %16s:%-5d\t%us\n", this->zone_id, this->addr,
            this->port, this->duration / 1000000000);
}


'