granicus.if.org Git - postgresql/blob - src/tools/fsync/test_fsync.c

   1 /*
   2  * $PostgreSQL: pgsql/src/tools/fsync/test_fsync.c,v 1.22 2009/05/08 14:06:27 momjian Exp $
   3  *
   4  *
   5  *      test_fsync.c
   6  *              test various fsync() methods
   7  */
   8
   9 #include "postgres.h"
  10
  11 #include "access/xlog_internal.h"
  12 #include "access/xlog.h"
  13 #include "access/xlogdefs.h"
  14
  15 #include <sys/types.h>
  16 #include <sys/stat.h>
  17 #include <fcntl.h>
  18 #include <stdio.h>
  19 #include <stdlib.h>
  20 #include <time.h>
  21 #include <sys/time.h>
  22 #include <unistd.h>
  23 #include <string.h>
  24
  25
  26 #ifdef WIN32
  27 #define FSYNC_FILENAME  "./test_fsync.out"
  28 #else
  29 /* /tmp might be a memory file system */
  30 #define FSYNC_FILENAME  "/var/tmp/test_fsync.out"
  31 #endif
  32
  33 #define WRITE_SIZE      (16 * 1024)
  34
  35 void            die(char *str);
  36 void            print_elapse(struct timeval start_t, struct timeval elapse_t);
  37
  38 int
  39 main(int argc, char *argv[])
  40 {
  41         struct timeval start_t;
  42         struct timeval elapse_t;
  43         int                     tmpfile,
  44                                 i,
  45                                 loops = 1000;
  46         char       *full_buf = (char *) malloc(XLOG_SEG_SIZE),
  47                            *buf;
  48         char       *filename = FSYNC_FILENAME;
  49
  50         if (argc > 2 && strcmp(argv[1], "-f") == 0)
  51         {
  52                 filename = argv[2];
  53                 argv += 2;
  54                 argc -= 2;
  55         }
  56
  57         if (argc > 1)
  58                 loops = atoi(argv[1]);
  59
  60         for (i = 0; i < XLOG_SEG_SIZE; i++)
  61                 full_buf[i] = 'a';
  62
  63         if ((tmpfile = open(filename, O_RDWR | O_CREAT, S_IRUSR | S_IWUSR, 0)) == -1)
  64                 die("Cannot open output file.");
  65         if (write(tmpfile, full_buf, XLOG_SEG_SIZE) != XLOG_SEG_SIZE)
  66                 die("write failed");
  67         /* fsync so later fsync's don't have to do it */
  68         if (fsync(tmpfile) != 0)
  69                 die("fsync failed");
  70         close(tmpfile);
  71
  72         buf = (char *) TYPEALIGN(ALIGNOF_XLOG_BUFFER, full_buf);
  73
  74         printf("Simple write timing:\n");
  75         /* write only */
  76         gettimeofday(&start_t, NULL);
  77         for (i = 0; i < loops; i++)
  78         {
  79                 if ((tmpfile = open(filename, O_RDWR, 0)) == -1)
  80                         die("Cannot open output file.");
  81                 if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
  82                         die("write failed");
  83                 close(tmpfile);
  84         }
  85         gettimeofday(&elapse_t, NULL);
  86         printf("\twrite                  ");
  87         print_elapse(start_t, elapse_t);
  88         printf("\n");
  89
  90         printf("\nCompare fsync times on write() and non-write() descriptor:\n");
  91         printf("(If the times are similar, fsync() can sync data written\n on a different descriptor.)\n");
  92
  93         /* write, fsync, close */
  94         gettimeofday(&start_t, NULL);
  95         for (i = 0; i < loops; i++)
  96         {
  97                 if ((tmpfile = open(filename, O_RDWR, 0)) == -1)
  98                         die("Cannot open output file.");
  99                 if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
 100                         die("write failed");
 101                 if (fsync(tmpfile) != 0)
 102                         die("fsync failed");
 103                 close(tmpfile);
 104                 if ((tmpfile = open(filename, O_RDWR, 0)) == -1)
 105                         die("Cannot open output file.");
 106                 /* do nothing but the open/close the tests are consistent. */
 107                 close(tmpfile);
 108         }
 109         gettimeofday(&elapse_t, NULL);
 110         printf("\twrite, fsync, close    ");
 111         print_elapse(start_t, elapse_t);
 112         printf("\n");
 113
 114         /* write, close, fsync */
 115         gettimeofday(&start_t, NULL);
 116         for (i = 0; i < loops; i++)
 117         {
 118                 if ((tmpfile = open(filename, O_RDWR, 0)) == -1)
 119                         die("Cannot open output file.");
 120                 if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
 121                         die("write failed");
 122                 close(tmpfile);
 123                 /* reopen file */
 124                 if ((tmpfile = open(filename, O_RDWR, 0)) == -1)
 125                         die("Cannot open output file.");
 126                 if (fsync(tmpfile) != 0)
 127                         die("fsync failed");
 128                 close(tmpfile);
 129         }
 130         gettimeofday(&elapse_t, NULL);
 131         printf("\twrite, close, fsync    ");
 132         print_elapse(start_t, elapse_t);
 133         printf("\n");
 134
 135         printf("\nCompare one o_sync write to two:\n");
 136
 137 #ifdef OPEN_SYNC_FLAG
 138         /* 16k o_sync write */
 139         if ((tmpfile = open(filename, O_RDWR | OPEN_SYNC_FLAG, 0)) == -1)
 140                 die("Cannot open output file.");
 141         gettimeofday(&start_t, NULL);
 142         for (i = 0; i < loops; i++)
 143                 if (write(tmpfile, buf, WRITE_SIZE) != WRITE_SIZE)
 144                         die("write failed");
 145         gettimeofday(&elapse_t, NULL);
 146         close(tmpfile);
 147         printf("\tone 16k o_sync write   ");
 148         print_elapse(start_t, elapse_t);
 149         printf("\n");
 150
 151         /* 2*8k o_sync writes */
 152         if ((tmpfile = open(filename, O_RDWR | OPEN_SYNC_FLAG, 0)) == -1)
 153                 die("Cannot open output file.");
 154         gettimeofday(&start_t, NULL);
 155         for (i = 0; i < loops; i++)
 156         {
 157                 if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
 158                         die("write failed");
 159                 if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
 160                         die("write failed");
 161         }
 162         gettimeofday(&elapse_t, NULL);
 163         close(tmpfile);
 164         printf("\ttwo 8k o_sync writes   ");
 165         print_elapse(start_t, elapse_t);
 166         printf("\n");
 167
 168         printf("\nCompare file sync methods with one 8k write:\n");
 169 #else
 170         printf("\t(o_sync unavailable)  ");
 171 #endif
 172         printf("\n");
 173
 174 #ifdef OPEN_DATASYNC_FLAG
 175         /* open_dsync, write */
 176         if ((tmpfile = open(filename, O_RDWR | O_DSYNC, 0)) == -1)
 177                 die("Cannot open output file.");
 178         gettimeofday(&start_t, NULL);
 179         for (i = 0; i < loops; i++)
 180                 if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
 181                         die("write failed");
 182         gettimeofday(&elapse_t, NULL);
 183         close(tmpfile);
 184         printf("\topen o_dsync, write    ");
 185         print_elapse(start_t, elapse_t);
 186         printf("\n");
 187 #ifdef OPEN_SYNC_FLAG
 188         /* open_fsync, write */
 189         if ((tmpfile = open(filename, O_RDWR | OPEN_SYNC_FLAG, 0)) == -1)
 190                 die("Cannot open output file.");
 191         gettimeofday(&start_t, NULL);
 192         for (i = 0; i < loops; i++)
 193                 if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
 194                         die("write failed");
 195         gettimeofday(&elapse_t, NULL);
 196         close(tmpfile);
 197         printf("\topen o_sync, write     ");
 198         print_elapse(start_t, elapse_t);
 199 #endif
 200 #else
 201         printf("\t(o_dsync unavailable)  ");
 202 #endif
 203         printf("\n");
 204
 205 #ifdef HAVE_FDATASYNC
 206         /* write, fdatasync */
 207         if ((tmpfile = open(filename, O_RDWR, 0)) == -1)
 208                 die("Cannot open output file.");
 209         gettimeofday(&start_t, NULL);
 210         for (i = 0; i < loops; i++)
 211         {
 212                 if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
 213                         die("write failed");
 214                 fdatasync(tmpfile);
 215         }
 216         gettimeofday(&elapse_t, NULL);
 217         close(tmpfile);
 218         printf("\twrite, fdatasync       ");
 219         print_elapse(start_t, elapse_t);
 220 #else
 221         printf("\t(fdatasync unavailable)");
 222 #endif
 223         printf("\n");
 224
 225         /* write, fsync, close */
 226         if ((tmpfile = open(filename, O_RDWR, 0)) == -1)
 227                 die("Cannot open output file.");
 228         gettimeofday(&start_t, NULL);
 229         for (i = 0; i < loops; i++)
 230         {
 231                 if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
 232                         die("write failed");
 233                 if (fsync(tmpfile) != 0)
 234                         die("fsync failed");
 235         }
 236         gettimeofday(&elapse_t, NULL);
 237         close(tmpfile);
 238         printf("\twrite, fsync,          ");
 239         print_elapse(start_t, elapse_t);
 240         printf("\n");
 241
 242         printf("\nCompare file sync methods with 2 8k writes:\n");
 243
 244 #ifdef OPEN_DATASYNC_FLAG
 245         /* open_dsync, write */
 246         if ((tmpfile = open(filename, O_RDWR | O_DSYNC, 0)) == -1)
 247                 die("Cannot open output file.");
 248         gettimeofday(&start_t, NULL);
 249         for (i = 0; i < loops; i++)
 250         {
 251                 if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
 252                         die("write failed");
 253                 if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
 254                         die("write failed");
 255         }
 256         gettimeofday(&elapse_t, NULL);
 257         close(tmpfile);
 258         printf("\topen o_dsync, write    ");
 259         print_elapse(start_t, elapse_t);
 260 #else
 261         printf("\t(o_dsync unavailable)  ");
 262 #endif
 263         printf("\n");
 264
 265 #ifdef OPEN_SYNC_FLAG
 266         /* open_fsync, write */
 267         if ((tmpfile = open(filename, O_RDWR | OPEN_SYNC_FLAG, 0)) == -1)
 268                 die("Cannot open output file.");
 269         gettimeofday(&start_t, NULL);
 270         for (i = 0; i < loops; i++)
 271         {
 272                 if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
 273                         die("write failed");
 274                 if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
 275                         die("write failed");
 276         }
 277         gettimeofday(&elapse_t, NULL);
 278         close(tmpfile);
 279         printf("\topen o_sync, write     ");
 280         print_elapse(start_t, elapse_t);
 281         printf("\n");
 282 #endif
 283
 284 #ifdef HAVE_FDATASYNC
 285         /* write, fdatasync */
 286         if ((tmpfile = open(filename, O_RDWR, 0)) == -1)
 287                 die("Cannot open output file.");
 288         gettimeofday(&start_t, NULL);
 289         for (i = 0; i < loops; i++)
 290         {
 291                 if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
 292                         die("write failed");
 293                 if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
 294                         die("write failed");
 295                 fdatasync(tmpfile);
 296         }
 297         gettimeofday(&elapse_t, NULL);
 298         close(tmpfile);
 299         printf("\twrite, fdatasync       ");
 300         print_elapse(start_t, elapse_t);
 301 #else
 302         printf("\t(fdatasync unavailable)");
 303 #endif
 304         printf("\n");
 305
 306         /* write, fsync, close */
 307         if ((tmpfile = open(filename, O_RDWR, 0)) == -1)
 308                 die("Cannot open output file.");
 309         gettimeofday(&start_t, NULL);
 310         for (i = 0; i < loops; i++)
 311         {
 312                 if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
 313                         die("write failed");
 314                 if (write(tmpfile, buf, WRITE_SIZE / 2) != WRITE_SIZE / 2)
 315                         die("write failed");
 316                 if (fsync(tmpfile) != 0)
 317                         die("fsync failed");
 318         }
 319         gettimeofday(&elapse_t, NULL);
 320         close(tmpfile);
 321         printf("\twrite, fsync,          ");
 322         print_elapse(start_t, elapse_t);
 323         printf("\n");
 324
 325         free(full_buf);
 326         unlink(filename);
 327
 328         return 0;
 329 }
 330
 331 void
 332 print_elapse(struct timeval start_t, struct timeval elapse_t)
 333 {
 334         if (elapse_t.tv_usec < start_t.tv_usec)
 335         {
 336                 elapse_t.tv_sec--;
 337                 elapse_t.tv_usec += 1000000;
 338         }
 339
 340         printf("%3ld.%06ld", (long) (elapse_t.tv_sec - start_t.tv_sec),
 341                    (long) (elapse_t.tv_usec - start_t.tv_usec));
 342 }
 343
 344 void
 345 die(char *str)
 346 {
 347         fprintf(stderr, "%s\n", str);
 348         exit(1);
 349 }