1 #include <errno.h>
2 #include <fcntl.h>
3 #include <stdbool.h>
4 #include <stdio.h>
5 #include <stdlib.h>
6 #include <string.h>
7 #include <sys/mman.h>
8 #include <sys/time.h>
9
10 #include "pagingtest.h"
11
pageinout_test(int test_runs,bool cache,unsigned long long file_size)12 int pageinout_test(int test_runs, bool cache, unsigned long long file_size) {
13 int fd;
14 char tmpname[] = "pageinoutXXXXXX";
15 unsigned char *vec;
16 int i;
17 unsigned long long j;
18 volatile char *buf;
19 int ret = -1;
20 int rc;
21 struct timeval begin_time, end_time, elapsed_time, total_time_in, total_time_out;
22 long pagesize = sysconf(_SC_PAGE_SIZE);
23
24 timerclear(&total_time_in);
25 timerclear(&total_time_out);
26
27 fd = create_tmp_file(tmpname, file_size);
28 if (fd < 0) {
29 return -1;
30 }
31
32 vec = alloc_mincore_vec(file_size);
33 if (vec == NULL) {
34 goto err_alloc;
35 }
36
37 buf = mmap(NULL, file_size, PROT_READ, MAP_PRIVATE, fd, 0);
38 if (buf == ((void *)-1)) {
39 fprintf(stderr, "Failed to mmap file: %s\n", strerror(errno));
40 goto err_mmap;
41 }
42
43 if (!check_caching((void *)buf, vec, file_size, false)) {
44 goto err;
45 }
46
47 if (!cache) {
48 //madvise and fadvise as random to prevent prefetching
49 rc = madvise((void *)buf, file_size, MADV_RANDOM) ||
50 posix_fadvise(fd, 0, file_size, POSIX_FADV_RANDOM);
51 if (rc) {
52 goto err;
53 }
54 }
55
56 for (i = 0; i < test_runs; i++) {
57 gettimeofday(&begin_time, NULL);
58 //read every page into the page cache
59 for (j = 0; j < file_size; j += pagesize) {
60 buf[j];
61 }
62 gettimeofday(&end_time, NULL);
63
64 timersub(&end_time, &begin_time, &elapsed_time);
65 timeradd(&total_time_in, &elapsed_time, &total_time_in);
66
67 if (!check_caching((void *)buf, vec, file_size, true)) {
68 goto err;
69 }
70
71 gettimeofday(&begin_time, NULL);
72 rc = madvise((void *)buf, file_size, MADV_DONTNEED) ||
73 posix_fadvise(fd, 0, file_size, POSIX_FADV_DONTNEED);
74 gettimeofday(&end_time, NULL);
75 if (rc) {
76 fprintf(stderr, "posix_fadvise/madvise DONTNEED failed\n");
77 goto err;
78 }
79
80 timersub(&end_time, &begin_time, &elapsed_time);
81 timeradd(&total_time_out, &elapsed_time, &total_time_out);
82
83 if (!check_caching((void *)buf, vec, file_size, false)) {
84 goto err;
85 }
86 }
87
88 printf("%scached page-in: %llu MB/s\n", cache ? "" : "un",
89 (file_size * test_runs * USEC_PER_SEC) /
90 (1024 * 1024 * (total_time_in.tv_sec * USEC_PER_SEC + total_time_in.tv_usec)));
91 printf("%scached page-out (clean): %llu MB/s\n", cache ? "" : "un",
92 (file_size * test_runs * USEC_PER_SEC) /
93 (1024 * 1024 * (total_time_out.tv_sec * USEC_PER_SEC + total_time_out.tv_usec)));
94
95 ret = 0;
96
97 err:
98 munmap((void *)buf, file_size);
99 err_mmap:
100 free(vec);
101 err_alloc:
102 close(fd);
103 return ret;
104 }
105