iostat.c revision 102067 
1/*
2 * Copyright (c) 1997, 1998, 2000, 2001  Kenneth D. Merry
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. The name of the author may not be used to endorse or promote products
14 *    derived from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 * $FreeBSD: head/usr.sbin/iostat/iostat.c 102067 2002-08-18 17:35:55Z bde $
29 */
30/*
31 * Parts of this program are derived from the original FreeBSD iostat
32 * program:
33 */
34/*-
35 * Copyright (c) 1986, 1991, 1993
36 *	The Regents of the University of California.  All rights reserved.
37 *
38 * Redistribution and use in source and binary forms, with or without
39 * modification, are permitted provided that the following conditions
40 * are met:
41 * 1. Redistributions of source code must retain the above copyright
42 *    notice, this list of conditions and the following disclaimer.
43 * 2. Redistributions in binary form must reproduce the above copyright
44 *    notice, this list of conditions and the following disclaimer in the
45 *    documentation and/or other materials provided with the distribution.
46 * 3. All advertising materials mentioning features or use of this software
47 *    must display the following acknowledgement:
48 *	This product includes software developed by the University of
49 *	California, Berkeley and its contributors.
50 * 4. Neither the name of the University nor the names of its contributors
51 *    may be used to endorse or promote products derived from this software
52 *    without specific prior written permission.
53 *
54 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
55 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
56 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
57 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
58 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
59 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
60 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
61 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
62 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
63 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
64 * SUCH DAMAGE.
65 */
66/*
67 * Ideas for the new iostat statistics output modes taken from the NetBSD
68 * version of iostat:
69 */
70/*
71 * Copyright (c) 1996 John M. Vinopal
72 * All rights reserved.
73 *
74 * Redistribution and use in source and binary forms, with or without
75 * modification, are permitted provided that the following conditions
76 * are met:
77 * 1. Redistributions of source code must retain the above copyright
78 *    notice, this list of conditions and the following disclaimer.
79 * 2. Redistributions in binary form must reproduce the above copyright
80 *    notice, this list of conditions and the following disclaimer in the
81 *    documentation and/or other materials provided with the distribution.
82 * 3. All advertising materials mentioning features or use of this software
83 *    must display the following acknowledgement:
84 *      This product includes software developed for the NetBSD Project
85 *      by John M. Vinopal.
86 * 4. The name of the author may not be used to endorse or promote products
87 *    derived from this software without specific prior written permission.
88 *
89 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
90 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
91 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
92 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
93 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
94 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
95 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
96 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
97 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
98 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
99 * SUCH DAMAGE.
100 */
101
102
103#include <sys/param.h>
104#include <sys/errno.h>
105#include <sys/dkstat.h>
106#include <sys/sysctl.h>
107
108#include <err.h>
109#include <ctype.h>
110#include <fcntl.h>
111#include <kvm.h>
112#include <nlist.h>
113#include <stdio.h>
114#include <stdlib.h>
115#include <string.h>
116#include <unistd.h>
117#include <limits.h>
118#include <devstat.h>
119#include <math.h>
120
121struct nlist namelist[] = {
122#define X_TK_NIN	0
123	{ "_tk_nin" },
124#define X_TK_NOUT	1
125	{ "_tk_nout" },
126#define X_CP_TIME	2
127	{ "_cp_time" },
128#define X_BOOTTIME	3
129	{ "_boottime" },
130#define X_END		3
131	{ NULL },
132};
133
134struct statinfo cur, last;
135int num_devices;
136struct device_selection *dev_select;
137int maxshowdevs;
138volatile sig_atomic_t headercount;
139int dflag = 0, Iflag = 0, Cflag = 0, Tflag = 0, oflag = 0, Kflag = 0;
140
141/* local function declarations */
142static void usage(void);
143static void needhdr(int signo);
144static void phdr(void);
145static void devstats(int perf_select, long double etime, int havelast);
146static void cpustats(void);
147static int readvar(kvm_t *kd, const char *name, int nlid, void *ptr,
148		   size_t len);
149
150static void
151usage(void)
152{
153	/*
154	 * We also support the following 'traditional' syntax:
155	 * iostat [drives] [wait [count]]
156	 * This isn't mentioned in the man page, or the usage statement,
157	 * but it is supported.
158	 */
159	fprintf(stderr, "usage: iostat [-CdhIKoT?] [-c count] [-M core]"
160		" [-n devs] [-N system]\n"
161		"\t      [-t type,if,pass] [-w wait] [drives]\n");
162}
163
164int
165main(int argc, char **argv)
166{
167	int c;
168	register int i;
169	int tflag = 0, hflag = 0, cflag = 0, wflag = 0, nflag = 0;
170	int count = 0, waittime = 0;
171	char *memf = NULL, *nlistf = NULL;
172	struct devstat_match *matches;
173	int num_matches = 0;
174        char errbuf[_POSIX2_LINE_MAX];
175	kvm_t *kd = NULL;
176	long generation;
177	int num_devices_specified;
178	int num_selected, num_selections;
179	long select_generation;
180	char **specified_devices;
181	devstat_select_mode select_mode;
182	int havelast = 0;
183
184	matches = NULL;
185	maxshowdevs = 3;
186
187	while ((c = getopt(argc, argv, "c:CdhIKM:n:N:ot:Tw:?")) != -1) {
188		switch(c) {
189			case 'c':
190				cflag++;
191				count = atoi(optarg);
192				if (count < 1)
193					errx(1, "count %d is < 1", count);
194				break;
195			case 'C':
196				Cflag++;
197				break;
198			case 'd':
199				dflag++;
200				break;
201			case 'h':
202				hflag++;
203				break;
204			case 'I':
205				Iflag++;
206				break;
207			case 'K':
208				Kflag++;
209				break;
210			case 'M':
211				memf = optarg;
212				break;
213			case 'n':
214				nflag++;
215				maxshowdevs = atoi(optarg);
216				if (maxshowdevs < 0)
217					errx(1, "number of devices %d is < 0",
218					     maxshowdevs);
219				break;
220			case 'N':
221				nlistf = optarg;
222				break;
223			case 'o':
224				oflag++;
225				break;
226			case 't':
227				tflag++;
228				if (devstat_buildmatch(optarg, &matches,
229						       &num_matches) != 0)
230					errx(1, "%s", devstat_errbuf);
231				break;
232			case 'T':
233				Tflag++;
234				break;
235			case 'w':
236				wflag++;
237				waittime = atoi(optarg);
238				if (waittime < 1)
239					errx(1, "wait time is < 1");
240				break;
241			default:
242				usage();
243				exit(1);
244				break;
245		}
246	}
247
248	argc -= optind;
249	argv += optind;
250
251	if (nlistf != NULL || memf != NULL) {
252		kd = kvm_openfiles(nlistf, memf, NULL, O_RDONLY, errbuf);
253
254		if (kd == NULL)
255			errx(1, "kvm_openfiles: %s", errbuf);
256
257		if (kvm_nlist(kd, namelist) == -1)
258			errx(1, "kvm_nlist: %s", kvm_geterr(kd));
259	}
260
261	/*
262	 * Make sure that the userland devstat version matches the kernel
263	 * devstat version.  If not, exit and print a message informing
264	 * the user of his mistake.
265	 */
266	if (devstat_checkversion(kd) < 0)
267		errx(1, "%s", devstat_errbuf);
268
269	/*
270	 * Make sure Tflag and/or Cflag are set if dflag == 0.  If dflag is
271	 * greater than 0, they may be 0 or non-zero.
272	 */
273	if (dflag == 0) {
274		Cflag = 1;
275		Tflag = 1;
276	}
277
278	/*
279	 * Figure out how many devices we should display.
280	 */
281	if (nflag == 0) {
282		if (oflag > 0) {
283			if ((dflag > 0) && (Cflag == 0) && (Tflag == 0))
284				maxshowdevs = 5;
285			else if ((dflag > 0) && (Tflag > 0) && (Cflag == 0))
286				maxshowdevs = 5;
287			else
288				maxshowdevs = 4;
289		} else {
290			if ((dflag > 0) && (Cflag == 0))
291				maxshowdevs = 4;
292			else
293				maxshowdevs = 3;
294		}
295	}
296
297	/* find out how many devices we have */
298	if ((num_devices = devstat_getnumdevs(kd)) < 0)
299		err(1, "can't get number of devices");
300
301	cur.dinfo = (struct devinfo *)malloc(sizeof(struct devinfo));
302	if (cur.dinfo == NULL)
303		err(1, "malloc failed");
304
305	last.dinfo = (struct devinfo *)malloc(sizeof(struct devinfo));
306	if (last.dinfo == NULL)
307		err(1, "malloc failed");
308
309	bzero(cur.dinfo, sizeof(struct devinfo));
310	bzero(last.dinfo, sizeof(struct devinfo));
311
312	/*
313	 * Grab all the devices.  We don't look to see if the list has
314	 * changed here, since it almost certainly has.  We only look for
315	 * errors.
316	 */
317	if (devstat_getdevs(kd, &cur) == -1)
318		errx(1, "%s", devstat_errbuf);
319
320	num_devices = cur.dinfo->numdevs;
321	generation = cur.dinfo->generation;
322
323	/*
324	 * If the user specified any devices on the command line, see if
325	 * they are in the list of devices we have now.
326	 */
327	specified_devices = (char **)malloc(sizeof(char *));
328	if (specified_devices == NULL)
329		err(1, "malloc failed");
330
331	for (num_devices_specified = 0; *argv; ++argv) {
332		if (isdigit(**argv))
333			break;
334		num_devices_specified++;
335		specified_devices = (char **)realloc(specified_devices,
336						     sizeof(char *) *
337						     num_devices_specified);
338		if (specified_devices == NULL)
339			err(1, "realloc failed");
340
341		specified_devices[num_devices_specified - 1] = *argv;
342
343	}
344	if (nflag == 0 && maxshowdevs < num_devices_specified)
345		maxshowdevs = num_devices_specified;
346
347	dev_select = NULL;
348
349	if ((num_devices_specified == 0) && (num_matches == 0))
350		select_mode = DS_SELECT_ADD;
351	else
352		select_mode = DS_SELECT_ONLY;
353
354	/*
355	 * At this point, selectdevs will almost surely indicate that the
356	 * device list has changed, so we don't look for return values of 0
357	 * or 1.  If we get back -1, though, there is an error.
358	 */
359	if (devstat_selectdevs(&dev_select, &num_selected,
360			       &num_selections, &select_generation, generation,
361			       cur.dinfo->devices, num_devices, matches,
362			       num_matches, specified_devices,
363			       num_devices_specified, select_mode, maxshowdevs,
364			       hflag) == -1)
365		errx(1, "%s", devstat_errbuf);
366
367	/*
368	 * Look for the traditional wait time and count arguments.
369	 */
370	if (*argv) {
371		waittime = atoi(*argv);
372
373		/* Let the user know he goofed, but keep going anyway */
374		if (wflag != 0)
375			warnx("discarding previous wait interval, using"
376			      " %d instead", waittime);
377		wflag++;
378
379		if (*++argv) {
380			count = atoi(*argv);
381			if (cflag != 0)
382				warnx("discarding previous count, using %d"
383				      " instead", count);
384			cflag++;
385		} else
386			count = -1;
387	}
388
389	/*
390	 * If the user specified a count, but not an interval, we default
391	 * to an interval of 1 second.
392	 */
393	if ((wflag == 0) && (cflag > 0))
394		waittime = 1;
395
396	/*
397	 * If the user specified a wait time, but not a count, we want to
398	 * go on ad infinitum.  This can be redundant if the user uses the
399	 * traditional method of specifying the wait, since in that case we
400	 * already set count = -1 above.  Oh well.
401	 */
402	if ((wflag > 0) && (cflag == 0))
403		count = -1;
404
405	bzero(&cur.cp_time, sizeof(cur.cp_time));
406	cur.tk_nout = 0;
407	cur.tk_nin = 0;
408
409	/*
410	 * Set the busy time to the system boot time, so the stats are
411	 * calculated since system boot.
412	 */
413	if (readvar(kd, "kern.boottime", X_BOOTTIME, &cur.busy_time,
414		    sizeof(cur.busy_time)) != 0)
415		exit(1);
416
417	/*
418	 * If the user stops the program (control-Z) and then resumes it,
419	 * print out the header again.
420	 */
421	(void)signal(SIGCONT, needhdr);
422
423	for (headercount = 1;;) {
424		struct devinfo *tmp_dinfo;
425		long tmp;
426		long double etime;
427
428		if (Tflag > 0) {
429			if ((readvar(kd, "kern.tty_nin", X_TK_NIN, &cur.tk_nin,
430			     sizeof(cur.tk_nin)) != 0)
431			 || (readvar(kd, "kern.tty_nout", X_TK_NOUT,
432			     &cur.tk_nout, sizeof(cur.tk_nout))!= 0)) {
433				Tflag = 0;
434				warnx("disabling TTY statistics");
435			}
436		 }
437
438		if (Cflag > 0) {
439			if (readvar(kd, "kern.cp_time", X_CP_TIME,
440			    &cur.cp_time, sizeof(cur.cp_time)) != 0) {
441				Cflag = 0;
442				warnx("disabling CPU time statistics");
443			}
444		}
445
446		if (!--headercount) {
447			phdr();
448			headercount = 20;
449		}
450
451		tmp_dinfo = last.dinfo;
452		last.dinfo = cur.dinfo;
453		cur.dinfo = tmp_dinfo;
454
455		last.busy_time = cur.busy_time;
456
457		/*
458		 * Here what we want to do is refresh our device stats.
459		 * devstat_getdevs() returns 1 when the device list has changed.
460		 * If the device list has changed, we want to go through
461		 * the selection process again, in case a device that we
462		 * were previously displaying has gone away.
463		 */
464		switch (devstat_getdevs(kd, &cur)) {
465		case -1:
466			errx(1, "%s", devstat_errbuf);
467			break;
468		case 1: {
469			int retval;
470
471			num_devices = cur.dinfo->numdevs;
472			generation = cur.dinfo->generation;
473			retval = devstat_selectdevs(&dev_select, &num_selected,
474						    &num_selections,
475						    &select_generation,
476						    generation,
477						    cur.dinfo->devices,
478						    num_devices, matches,
479						    num_matches,
480						    specified_devices,
481						    num_devices_specified,
482						    select_mode, maxshowdevs,
483						    hflag);
484			switch(retval) {
485			case -1:
486				errx(1, "%s", devstat_errbuf);
487				break;
488			case 1:
489				phdr();
490				headercount = 20;
491				break;
492			default:
493				break;
494			}
495			break;
496		}
497		default:
498			break;
499		}
500
501		/*
502		 * We only want to re-select devices if we're in 'top'
503		 * mode.  This is the only mode where the devices selected
504		 * could actually change.
505		 */
506		if (hflag > 0) {
507			int retval;
508			retval = devstat_selectdevs(&dev_select, &num_selected,
509						    &num_selections,
510						    &select_generation,
511						    generation,
512						    cur.dinfo->devices,
513						    num_devices, matches,
514						    num_matches,
515						    specified_devices,
516						    num_devices_specified,
517						    select_mode, maxshowdevs,
518						    hflag);
519			switch(retval) {
520			case -1:
521				errx(1,"%s", devstat_errbuf);
522				break;
523			case 1:
524				phdr();
525				headercount = 20;
526				break;
527			default:
528				break;
529			}
530		}
531
532		if (Tflag > 0) {
533			tmp = cur.tk_nin;
534			cur.tk_nin -= last.tk_nin;
535			last.tk_nin = tmp;
536			tmp = cur.tk_nout;
537			cur.tk_nout -= last.tk_nout;
538			last.tk_nout = tmp;
539		}
540
541		etime = devstat_compute_etime(cur.busy_time, last.busy_time);
542
543		if (etime == 0.0)
544			etime = 1.0;
545
546		for (i = 0; i < CPUSTATES; i++) {
547			tmp = cur.cp_time[i];
548			cur.cp_time[i] -= last.cp_time[i];
549			last.cp_time[i] = tmp;
550		}
551
552		if (Tflag > 0)
553			printf("%4.0Lf%5.0Lf", cur.tk_nin / etime,
554				cur.tk_nout/etime);
555
556		devstats(hflag, etime, havelast);
557
558		if (Cflag > 0)
559			cpustats();
560
561		printf("\n");
562		fflush(stdout);
563
564		if (count >= 0 && --count <= 0)
565			break;
566
567		sleep(waittime);
568		havelast = 1;
569	}
570
571	exit(0);
572}
573
574/*
575 * Force a header to be prepended to the next output.
576 */
577void
578needhdr(int signo)
579{
580
581        headercount = 1;
582}
583
584static void
585phdr(void)
586{
587	register int i;
588	int printed;
589
590	if (Tflag > 0)
591		(void)printf("      tty");
592	for (i = 0, printed=0;(i < num_devices) && (printed < maxshowdevs);i++){
593		int di;
594		if ((dev_select[i].selected != 0)
595		 && (dev_select[i].selected <= maxshowdevs)) {
596			di = dev_select[i].position;
597			if (oflag > 0)
598				(void)printf("%12.6s%d ",
599					    cur.dinfo->devices[di].device_name,
600					    cur.dinfo->devices[di].unit_number);
601			else
602				printf("%15.6s%d ",
603					    cur.dinfo->devices[di].device_name,
604					    cur.dinfo->devices[di].unit_number);
605			printed++;
606		}
607	}
608	if (Cflag > 0)
609		(void)printf("            cpu\n");
610	else
611		(void)printf("\n");
612
613	if (Tflag > 0)
614		(void)printf(" tin tout");
615
616	for (i=0, printed = 0;(i < num_devices) && (printed < maxshowdevs);i++){
617		if ((dev_select[i].selected != 0)
618		 && (dev_select[i].selected <= maxshowdevs)) {
619			if (oflag > 0) {
620				if (Iflag == 0)
621					(void)printf(" sps tps msps ");
622				else
623					(void)printf(" blk xfr msps ");
624			} else {
625				if (Iflag == 0)
626					printf("  KB/t tps  MB/s ");
627				else
628					printf("  KB/t xfrs   MB ");
629			}
630			printed++;
631		}
632	}
633	if (Cflag > 0)
634		(void)printf(" us ni sy in id\n");
635	else
636		printf("\n");
637
638}
639
640static void
641devstats(int perf_select, long double etime, int havelast)
642{
643	register int dn;
644	long double transfers_per_second;
645	long double kb_per_transfer, mb_per_second;
646	u_int64_t total_bytes, total_transfers, total_blocks;
647	long double total_mb;
648	long double blocks_per_second, ms_per_transaction;
649
650	for (dn = 0; dn < num_devices; dn++) {
651		int di;
652
653		if (((perf_select == 0) && (dev_select[dn].selected == 0))
654		 || (dev_select[dn].selected > maxshowdevs))
655			continue;
656
657		di = dev_select[dn].position;
658
659		if (devstat_compute_statistics(&cur.dinfo->devices[di],
660		    havelast ? &last.dinfo->devices[di] : NULL, etime,
661		    DSM_TOTAL_BYTES, &total_bytes,
662		    DSM_TOTAL_TRANSFERS, &total_transfers,
663		    DSM_TOTAL_BLOCKS, &total_blocks,
664		    DSM_KB_PER_TRANSFER, &kb_per_transfer,
665		    DSM_TRANSFERS_PER_SECOND, &transfers_per_second,
666		    DSM_MB_PER_SECOND, &mb_per_second,
667		    DSM_BLOCKS_PER_SECOND, &blocks_per_second,
668		    DSM_MS_PER_TRANSACTION, &ms_per_transaction,
669		    DSM_NONE) != 0)
670			errx(1, "%s", devstat_errbuf);
671
672		if (perf_select != 0) {
673			dev_select[dn].bytes = total_bytes;
674			if ((dev_select[dn].selected == 0)
675			 || (dev_select[dn].selected > maxshowdevs))
676				continue;
677		}
678
679		if (Kflag) {
680			int block_size = cur.dinfo->devices[di].block_size;
681			total_blocks = total_blocks * (block_size ?
682						       block_size : 512) / 1024;
683		}
684
685		if (oflag > 0) {
686			int msdig = (ms_per_transaction < 100.0) ? 1 : 0;
687
688			if (Iflag == 0)
689				printf("%4.0Lf%4.0Lf%5.*Lf ",
690				       blocks_per_second,
691				       transfers_per_second,
692				       msdig,
693				       ms_per_transaction);
694			else
695				printf("%4.1qu%4.1qu%5.*Lf ",
696				       total_blocks,
697				       total_transfers,
698				       msdig,
699				       ms_per_transaction);
700		} else {
701			if (Iflag == 0)
702				printf(" %5.2Lf %3.0Lf %5.2Lf ",
703				       kb_per_transfer,
704				       transfers_per_second,
705				       mb_per_second);
706			else {
707				total_mb = total_bytes;
708				total_mb /= 1024 * 1024;
709
710				printf(" %5.2Lf %3.1qu %5.2Lf ",
711				       kb_per_transfer,
712				       total_transfers,
713				       total_mb);
714			}
715		}
716	}
717}
718
719static void
720cpustats(void)
721{
722	register int state;
723	double time;
724
725	time = 0.0;
726
727	for (state = 0; state < CPUSTATES; ++state)
728		time += cur.cp_time[state];
729	for (state = 0; state < CPUSTATES; ++state)
730		printf("%3.0f",
731		       rint(100. * cur.cp_time[state] / (time ? time : 1)));
732}
733
734static int
735readvar(kvm_t *kd, const char *name, int nlid, void *ptr, size_t len)
736{
737	if (kd != NULL) {
738		ssize_t nbytes;
739
740		nbytes = kvm_read(kd, nlid, ptr, len);
741
742		if (nbytes == 0) {
743			warnx("kvm_read(%s): %s", name, kvm_geterr(kd));
744			return (1);
745		}
746		if (nbytes != len) {
747			warnx("kvm_read(%s): expected %lu bytes, got %ld bytes",
748			      name, (unsigned long)len, (long)nbytes);
749			return (1);
750		}
751	} else {
752		size_t nlen = len;
753
754		if (sysctlbyname(name, ptr, &nlen, NULL, 0) == -1) {
755			warn("sysctl(%s...) failed", name);
756			return (1);
757		}
758		if (nlen != len) {
759			warnx("sysctl(%s...): expected %lu, got %lu", name,
760			      (unsigned long)len, (unsigned long)nlen);
761			return (1);
762		}
763	}
764	return (0);
765}
766