4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 only,
8 * as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License version 2 for more details (a copy is included
14 * in the LICENSE file that accompanied this code).
16 * You should have received a copy of the GNU General Public License
17 * version 2 along with this program; If not, see
18 * http://www.gnu.org/licenses/gpl-2.0.html
23 * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Use is subject to license terms.
27 * This file is part of Lustre, http://www.lustre.org/
28 * Lustre is a trademark of Sun Microsystems, Inc.
30 * lustre/tests/reads.c
34 * Author: Nikita Danilov <nikita@clusterfs.com>
37 #define _XOPEN_SOURCE 500 /* for pread(2) */
47 #include <sys/types.h>
50 static void usage(void)
52 printf("reads: read random or stride chunks of a file.\n");
54 printf("reads -f <filename> -s <filesize> -b <buffersize>"
55 "-a <adjacent reads> [-v] [-h] [-C] [-l <stride_length> ] "
56 "[ -o <stride_offset> ] [-S <seed>] [-n <iterations>]"
57 "[-w <width>] [-t <timelimit>]\n");
61 BSIZE_DEFAULT = 16 * 4096
64 #define LOG(level, ...) \
66 if ((level) <= verbosity) \
67 fprintf(stderr, __VA_ARGS__); \
87 int main(int argc, char **argv)
89 int verbosity = LOG_CRIT;
96 unsigned int seed = 0;
97 unsigned long iterations = 0;
98 unsigned long timelimit = 24 * 3600;
99 unsigned long stride_length = 0;
100 unsigned long stride_offset = 0;
104 unsigned long nblocks;
108 struct timeval start;
117 opt = getopt(argc, argv, "f:s:b:va:hCS:n:t:l:o:w:");
122 LOG(LOG_CRIT, "Unable to parse command line.\n");
130 fname = strdup(optarg);
133 size = strtol(optarg, &term, 0);
134 if (term == optarg) {
135 fprintf (stderr, "Can't parse size %s\n", optarg);
141 bsize = strtol(optarg, &term, 0);
142 if (term == optarg) {
143 fprintf (stderr, "Can't parse bsize %s\n", optarg);
149 ad = (int)strtol(optarg, &term, 0);
150 if (term == optarg) {
151 fprintf (stderr, "Can't parse ad %s\n", optarg);
160 seed = strtol(optarg, &term, 0);
161 if (term == optarg) {
162 fprintf (stderr, "Can't parse seed %s\n", optarg);
168 iterations = strtol(optarg, &term, 0);
169 if (term == optarg) {
170 fprintf (stderr, "Can't parse seed %s\n", optarg);
178 timelimit = strtol(optarg, &term, 0);
179 if (term == optarg) {
180 fprintf (stderr, "Can't parse seed %s\n", optarg);
186 stride_length = strtol(optarg, &term, 0);
187 if (term == optarg) {
188 fprintf (stderr, "Can't parse seed %s\n", optarg);
194 stride_offset = strtol(optarg, &term, 0);
195 if (term == optarg) {
196 fprintf (stderr, "Can't parse seed %s\n", optarg);
202 width = (int)strtol(optarg, &term, 0);
203 if (term == optarg) {
204 fprintf (stderr, "Can't parse seed %s\n", optarg);
212 if (fname == NULL || size == 0 || bsize == 0 || ad <= 0) {
218 nblocks = size / bsize;
221 LOG(LOG_CRIT, "malloc(%lu) failure: %s\n", (long)bsize,
226 fd = open(fname, (preclean ? O_RDWR : O_RDONLY) | O_CREAT, 0700);
228 LOG(LOG_CRIT, "malloc(\"%s\") failure: %s\n", fname,
236 LOG(LOG_INFO, "precleaning");
237 for (i = 0, towrite = size; towrite > 0; towrite -= ret) {
238 count = bsize < towrite ? bsize : towrite;
239 memset(buf, bsize, seed + i++);
240 ret = write(fd, buf, count);
242 LOG(LOG_CRIT, "write() failure: %s\n",
251 gettimeofday(&start, NULL);
252 timelimit += start.tv_sec;
253 for (i = 0; !iterations || i < iterations; i ++) {
254 unsigned long block_nr;
258 block_nr = (unsigned long)(i*stride_length +
259 stride_offset) % nblocks;
261 block_nr = (unsigned long)((double)nblocks*rand()/
264 LOG(LOG_INFO, "\n%9lu: ", i);
265 LOG(LOG_INFO, "%7lu ", block_nr);
266 for (j = 0; j < ad; j++) {
267 ret = pread(fd, buf, bsize, (block_nr + j) * bsize);
270 "pread(...%zi, %li) got: %zi, %s\n", bsize,
271 block_nr * bsize, ret, strerror(errno));
276 gettimeofday(&stop, NULL);
277 if (stop.tv_sec > timelimit)
281 usecs = (stop.tv_sec - start.tv_sec) * 1000000. +
282 stop.tv_usec - start.tv_usec;
283 printf("\n%fs, %gMB/s\n", usecs / 1000000.,
284 (double)bsize * ad * i / usecs);