1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
|
/*
* Copyright (C) 2010 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* A simple test of emmc random read and write performance. When testing write
* performance, try it twice, once with O_SYNC compiled in, and once with it commented
* out. Without O_SYNC, the close(2) blocks until all the dirty buffers are written
* out, but the numbers tend to be higher.
*/
#define _LARGEFILE64_SOURCE
#include <string.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/time.h>
#include <stdlib.h>
#include <unistd.h>
#define TST_BLK_SIZE 4096
/* Number of seconds to run the test */
#define TEST_LEN 10
static void usage(void) {
fprintf(stderr, "Usage: rand_emmc_perf [ -r | -w ] [-o] <size_in_mb> <block_dev>\n");
exit(1);
}
int main(int argc, char *argv[])
{
long max_blocks;
int fd, fd2, write_mode = 0, iops = 0;
struct timeval start, end, res;
unsigned int seed;
char buf[TST_BLK_SIZE] = { 0 };
int c;
int o_sync = 0;
while ((c = getopt(argc, argv, "+rwo")) != -1) {
switch (c) {
case '?':
default:
usage();
break;
case 'r':
/* Do nothing, read mode is the default */
break;
case 'w':
write_mode = 1;
break;
case 'o':
o_sync = O_SYNC;
break;
}
}
if (o_sync && !write_mode) {
/* Can only specify o_sync in write mode. Probably doesn't matter,
* but clear o_sync if in read mode */
o_sync = 0;
}
if ((argc - optind) != 2) {
usage();
}
/* Size is given in megabytes, so compute the number of TST_BLK_SIZE blocks. */
max_blocks = atol(argv[optind]) * ((1024*1024) / TST_BLK_SIZE);
if ((fd = open(argv[optind + 1], O_RDWR | o_sync)) < 0) {
fprintf(stderr, "Cannot open block device %s\n", argv[optind + 1]);
exit(1);
}
fd2 = open("/dev/urandom", O_RDONLY);
if (fd2 < 0) {
fprintf(stderr, "Cannot open /dev/urandom\n");
}
if (read(fd2, &seed, sizeof(seed)) != sizeof(seed)) {
fprintf(stderr, "Cannot read /dev/urandom\n");
}
close(fd2);
srand(seed);
res.tv_sec = 0;
gettimeofday(&start, 0);
while (res.tv_sec < TEST_LEN) {
if (lseek64(fd, (rand() % max_blocks) * TST_BLK_SIZE, SEEK_SET) < 0) {
fprintf(stderr, "lseek64 failed\n");
}
if (write_mode) {
if (write(fd, buf, sizeof(buf)) != sizeof(buf)) {
fprintf(stderr, "Short write\n");
}
} else {
if (read(fd, buf, sizeof(buf)) != sizeof(buf)) {
fprintf(stderr, "Short read\n");
}
}
iops++;
gettimeofday(&end, 0);
timersub(&end, &start, &res);
}
close(fd);
/* The close can take a while when in write_mode as buffers are flushed.
* So get the time again. */
gettimeofday(&end, 0);
timersub(&end, &start, &res);
printf("%d iops/sec\n", iops / (int) res.tv_sec);
exit(0);
}
|
