xref: /freebsd/share/dtrace/disklatencycmd (revision eb69d1f144a6fcc765d1b9d44a5ae8082353e70b)
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
33/* from http://www.mail-archive.com/dtrace-discuss@opensolaris.org/msg03755.html */
34#pragma D option aggsize=8m
35#pragma D option bufsize=16m
36#pragma D option dynvarsize=32m
37/*
38#pragma D option aggrate=0
39#pragma D option cleanrate=50Hz
40*/
41
42dtrace:::BEGIN
43{
44	printf("Tracing... Hit Ctrl-C to end.\n");
45	dstart = timestamp;
46}
47
48io:::start
49{
50	start_time[arg0] = timestamp;
51}
52
53io:::done
54/this->start = start_time[arg0]/
55{
56	this->delta = (timestamp - this->start) / 1000;
57	@q[args[1]->device_name, args[1]->unit_number] =
58	    lquantize(this->delta, 4000, 80000, 4000);
59	@max[args[1]->device_name, args[1]->unit_number] = max(this->delta);
60	@avg[args[1]->device_name, args[1]->unit_number] = avg(this->delta);
61	@stddev[args[1]->device_name, args[1]->unit_number] = stddev(this->delta);
62	start_time[arg0] = 0;
63}
64
65dtrace:::END
66{
67	printf("total time, us: %d\n", (timestamp - dstart) / 1000);
68	printa("   %s (%d), us:\n%@d\n", @q);
69	printa("max%s (%d), us: %@d\n", @max);
70	printa("avg%s (%d), us: %@d\n", @avg);
71	printa("stddev%s (%d), us: %@d\n", @stddev);
72}
73