#!/usr/sbin/dtrace -s

#pragma D option quiet
#pragma D option dynvarsize=16m

dtrace:::BEGIN
{
	printf("Tracing... Hit Ctrl-C to end.\n");
}

io:::start
{
	start_time[arg0] = timestamp;
}

io:::done
/this->start = start_time[arg0]/
{
	this->delta = (timestamp - this->start) / 1000;
	@q[args[1]->device_name, args[1]->unit_number] =
	    lquantize(this->delta, 4000, 80000, 4000);
	@max[args[1]->device_name, args[1]->unit_number] = max(this->delta);
	@avg[args[1]->device_name, args[1]->unit_number] = avg(this->delta);
	@stddev[args[1]->device_name, args[1]->unit_number] = stddev(this->delta);
	start_time[arg0] = 0;
}

tick-10s
{
	printa("   %s (%d), us:\n%@d\n", @q);
	printa("max%s (%d), us:\n%@d\n", @max);
	printa("avg%s (%d), us:\n%@d\n", @avg);
	printa("stddev%s (%d), us:\n%@d\n", @stddev);

	clear(@q);
	clear(@max);
	clear(@avg);
	clear(@stddev);
}