xref: /freebsd/share/dtrace/disklatency (revision 0957b409)
1#!/usr/sbin/dtrace -s
2/*-
3 * Copyright 2014 John-Mark Gurney.
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 *
27 *	$FreeBSD$
28 *
29 */
30
31#pragma D option quiet
32#pragma D option dynvarsize=16m
33
34dtrace:::BEGIN
35{
36	printf("Tracing... Hit Ctrl-C to end.\n");
37}
38
39io:::start
40{
41	start_time[arg0] = timestamp;
42}
43
44io:::done
45/this->start = start_time[arg0]/
46{
47	this->delta = (timestamp - this->start) / 1000;
48	@q[args[1]->device_name, args[1]->unit_number] =
49	    lquantize(this->delta, 4000, 80000, 4000);
50	@max[args[1]->device_name, args[1]->unit_number] = max(this->delta);
51	@avg[args[1]->device_name, args[1]->unit_number] = avg(this->delta);
52	@stddev[args[1]->device_name, args[1]->unit_number] = stddev(this->delta);
53	start_time[arg0] = 0;
54}
55
56tick-10s
57{
58	printa("   %s (%d), us:\n%@d\n", @q);
59	printa("max%s (%d), us:\n%@d\n", @max);
60	printa("avg%s (%d), us:\n%@d\n", @avg);
61	printa("stddev%s (%d), us:\n%@d\n", @stddev);
62
63	clear(@q);
64	clear(@max);
65	clear(@avg);
66	clear(@stddev);
67}
68