src/proc_diskstats.c

   1 #include "common.h"
   2
   3 #define RRD_TYPE_DISK "disk"
   4
   5 #define DISK_TYPE_PHYSICAL  1
   6 #define DISK_TYPE_PARTITION 2
   7 #define DISK_TYPE_CONTAINER 3
   8
   9 static int check_for_new_mountpoints_every = 15;
  10
  11 static struct disk {
  12     char *disk;             // the name of the disk (sda, sdb, etc)
  13     unsigned long major;
  14     unsigned long minor;
  15     int sector_size;
  16     int type;
  17
  18     char *mount_point;
  19
  20     // disk options caching
  21     int configured;
  22     int do_io;
  23     int do_ops;
  24     int do_mops;
  25     int do_iotime;
  26     int do_qops;
  27     int do_util;
  28     int do_backlog;
  29
  30     struct disk *next;
  31 } *disk_root = NULL;
  32
  33 static struct mountinfo *disk_mountinfo_root = NULL;
  34
  35 static inline void mountinfo_reload(int force) {
  36     static time_t last_loaded = 0;
  37     time_t now = now_realtime_sec();
  38
  39     if(force || now - last_loaded >= check_for_new_mountpoints_every) {
  40         // mountinfo_free() can be called with NULL disk_mountinfo_root
  41         mountinfo_free(disk_mountinfo_root);
  42
  43         // re-read mountinfo in case something changed
  44         disk_mountinfo_root = mountinfo_read(0);
  45
  46         last_loaded = now;
  47     }
  48 }
  49
  50 static struct disk *get_disk(unsigned long major, unsigned long minor, char *disk) {
  51     static char path_to_get_hw_sector_size[FILENAME_MAX + 1] = "";
  52     static char path_to_get_hw_sector_size_partitions[FILENAME_MAX + 1] = "";
  53     static char path_find_block_device[FILENAME_MAX + 1] = "";
  54     struct disk *d;
  55
  56     // search for it in our RAM list.
  57     // this is sequential, but since we just walk through
  58     // and the number of disks / partitions in a system
  59     // should not be that many, it should be acceptable
  60     for(d = disk_root; d ; d = d->next)
  61         if(unlikely(d->major == major && d->minor == minor))
  62             break;
  63
  64     // if we found it, return it
  65     if(likely(d))
  66         return d;
  67
  68     // not found
  69     // create a new disk structure
  70     d = (struct disk *)mallocz(sizeof(struct disk));
  71
  72     d->disk = strdupz(disk);
  73     d->major = major;
  74     d->minor = minor;
  75     d->type = DISK_TYPE_PHYSICAL; // Default type. Changed later if not correct.
  76     d->configured = 0;
  77     d->sector_size = 512; // the default, will be changed below
  78     d->next = NULL;
  79
  80     // append it to the list
  81     if(unlikely(!disk_root))
  82         disk_root = d;
  83     else {
  84         struct disk *last;
  85         for(last = disk_root; last->next ;last = last->next);
  86         last->next = d;
  87     }
  88
  89     // ------------------------------------------------------------------------
  90     // find the type of the device
  91
  92     char buffer[FILENAME_MAX + 1];
  93
  94     // get the default path for finding info about the block device
  95     if(unlikely(!path_find_block_device[0])) {
  96         snprintfz(buffer, FILENAME_MAX, "%s%s", global_host_prefix, "/sys/dev/block/%lu:%lu/%s");
  97         snprintfz(path_find_block_device, FILENAME_MAX, "%s", config_get("plugin:proc:/proc/diskstats", "path to get block device infos", buffer));
  98     }
  99
 100     // find if it is a partition
 101     // by checking if /sys/dev/block/MAJOR:MINOR/partition is readable.
 102     snprintfz(buffer, FILENAME_MAX, path_find_block_device, major, minor, "partition");
 103     if(likely(access(buffer, R_OK) == 0)) {
 104         d->type = DISK_TYPE_PARTITION;
 105     }
 106     else {
 107         // find if it is a container
 108         // by checking if /sys/dev/block/MAJOR:MINOR/slaves has entries
 109         snprintfz(buffer, FILENAME_MAX, path_find_block_device, major, minor, "slaves/");
 110         DIR *dirp = opendir(buffer);
 111         if(likely(dirp != NULL)) {
 112             struct dirent *dp;
 113             while( (dp = readdir(dirp)) ) {
 114                 // . and .. are also files in empty folders.
 115                 if(unlikely(strcmp(dp->d_name, ".") == 0 || strcmp(dp->d_name, "..") == 0)) {
 116                     continue;
 117                 }
 118
 119                 d->type = DISK_TYPE_CONTAINER;
 120
 121                 // Stop the loop after we found one file.
 122                 break;
 123             }
 124             if(unlikely(closedir(dirp) == -1))
 125                 error("Unable to close dir %s", buffer);
 126         }
 127     }
 128
 129     // ------------------------------------------------------------------------
 130     // check if we can find its mount point
 131
 132     // mountinfo_find() can be called with NULL disk_mountinfo_root
 133     struct mountinfo *mi = mountinfo_find(disk_mountinfo_root, d->major, d->minor);
 134     if(unlikely(mi))
 135         d->mount_point = strdupz(mi->mount_point);
 136     else
 137         d->mount_point = NULL;
 138
 139     // ------------------------------------------------------------------------
 140     // find the disk sector size
 141
 142     if(unlikely(!path_to_get_hw_sector_size[0])) {
 143         snprintfz(buffer, FILENAME_MAX, "%s%s", global_host_prefix, "/sys/block/%s/queue/hw_sector_size");
 144         snprintfz(path_to_get_hw_sector_size, FILENAME_MAX, "%s", config_get("plugin:proc:/proc/diskstats", "path to get h/w sector size", buffer));
 145     }
 146     if(unlikely(!path_to_get_hw_sector_size_partitions[0])) {
 147         snprintfz(buffer, FILENAME_MAX, "%s%s", global_host_prefix, "/sys/dev/block/%lu:%lu/subsystem/%s/../queue/hw_sector_size");
 148         snprintfz(path_to_get_hw_sector_size_partitions, FILENAME_MAX, "%s", config_get("plugin:proc:/proc/diskstats", "path to get h/w sector size for partitions", buffer));
 149     }
 150
 151     {
 152         char tf[FILENAME_MAX + 1], *t;
 153         strncpyz(tf, d->disk, FILENAME_MAX);
 154
 155         // replace all / with !
 156         for(t = tf; *t ;t++)
 157             if(unlikely(*t == '/')) *t = '!';
 158
 159         if(likely(d->type == DISK_TYPE_PARTITION))
 160             snprintfz(buffer, FILENAME_MAX, path_to_get_hw_sector_size_partitions, d->major, d->minor, tf);
 161         else
 162             snprintfz(buffer, FILENAME_MAX, path_to_get_hw_sector_size, tf);
 163
 164         FILE *fpss = fopen(buffer, "r");
 165         if(likely(fpss)) {
 166             char buffer2[1024 + 1];
 167             char *tmp = fgets(buffer2, 1024, fpss);
 168
 169             if(likely(tmp)) {
 170                 d->sector_size = atoi(tmp);
 171                 if(unlikely(d->sector_size <= 0)) {
 172                     error("Invalid sector size %d for device %s in %s. Assuming 512.", d->sector_size, d->disk, buffer);
 173                     d->sector_size = 512;
 174                 }
 175             }
 176             else error("Cannot read data for sector size for device %s from %s. Assuming 512.", d->disk, buffer);
 177
 178             fclose(fpss);
 179         }
 180         else error("Cannot read sector size for device %s from %s. Assuming 512.", d->disk, buffer);
 181     }
 182
 183     return d;
 184 }
 185
 186 static inline int is_major_enabled(int major) {
 187     static char *major_configs = NULL;
 188     static size_t major_size = 0;
 189
 190     if(major < 0) return 1;
 191
 192     size_t wanted_size = (size_t)major + 1;
 193
 194     if(major_size < wanted_size) {
 195         major_configs = reallocz(major_configs, wanted_size);
 196
 197         size_t i;
 198         for(i = major_size; i < wanted_size ; i++)
 199             major_configs[i] = -1;
 200
 201         major_size = wanted_size;
 202     }
 203
 204     if(major_configs[major] == -1) {
 205         char buffer[CONFIG_MAX_NAME + 1];
 206         snprintfz(buffer, CONFIG_MAX_NAME, "performance metrics for disks with major %d", major);
 207         major_configs[major] = (char)config_get_boolean("plugin:proc:/proc/diskstats", buffer, 1);
 208     }
 209
 210     return major_configs[major];
 211 }
 212
 213 int do_proc_diskstats(int update_every, usec_t dt) {
 214     (void)dt;
 215
 216     static procfile *ff = NULL;
 217     static int  global_enable_new_disks_detected_at_runtime = CONFIG_ONDEMAND_YES,
 218                 global_enable_performance_for_physical_disks = CONFIG_ONDEMAND_ONDEMAND,
 219                 global_enable_performance_for_virtual_disks = CONFIG_ONDEMAND_ONDEMAND,
 220                 global_enable_performance_for_partitions = CONFIG_ONDEMAND_NO,
 221                 global_do_io = CONFIG_ONDEMAND_ONDEMAND,
 222                 global_do_ops = CONFIG_ONDEMAND_ONDEMAND,
 223                 global_do_mops = CONFIG_ONDEMAND_ONDEMAND,
 224                 global_do_iotime = CONFIG_ONDEMAND_ONDEMAND,
 225                 global_do_qops = CONFIG_ONDEMAND_ONDEMAND,
 226                 global_do_util = CONFIG_ONDEMAND_ONDEMAND,
 227                 global_do_backlog = CONFIG_ONDEMAND_ONDEMAND,
 228                 globals_initialized = 0;
 229
 230     if(unlikely(!globals_initialized)) {
 231         global_enable_new_disks_detected_at_runtime = config_get_boolean("plugin:proc:/proc/diskstats", "enable new disks detected at runtime", global_enable_new_disks_detected_at_runtime);
 232
 233         global_enable_performance_for_physical_disks = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "performance metrics for physical disks", global_enable_performance_for_physical_disks);
 234         global_enable_performance_for_virtual_disks = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "performance metrics for virtual disks", global_enable_performance_for_virtual_disks);
 235         global_enable_performance_for_partitions = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "performance metrics for partitions", global_enable_performance_for_partitions);
 236
 237         global_do_io      = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "bandwidth for all disks", global_do_io);
 238         global_do_ops     = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "operations for all disks", global_do_ops);
 239         global_do_mops    = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "merged operations for all disks", global_do_mops);
 240         global_do_iotime  = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "i/o time for all disks", global_do_iotime);
 241         global_do_qops    = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "queued operations for all disks", global_do_qops);
 242         global_do_util    = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "utilization percentage for all disks", global_do_util);
 243         global_do_backlog = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "backlog for all disks", global_do_backlog);
 244
 245         check_for_new_mountpoints_every = (int)config_get_number("plugin:proc:/proc/diskstats", "check for new mount points every", check_for_new_mountpoints_every);
 246         if(check_for_new_mountpoints_every < update_every)
 247             check_for_new_mountpoints_every = update_every;
 248
 249         globals_initialized = 1;
 250     }
 251
 252     // --------------------------------------------------------------------------
 253     // this is smart enough not to reload it every time
 254
 255     mountinfo_reload(0);
 256
 257     // --------------------------------------------------------------------------
 258
 259     if(unlikely(!ff)) {
 260         char filename[FILENAME_MAX + 1];
 261         snprintfz(filename, FILENAME_MAX, "%s%s", global_host_prefix, "/proc/diskstats");
 262         ff = procfile_open(config_get("plugin:proc:/proc/diskstats", "filename to monitor", filename), " \t", PROCFILE_FLAG_DEFAULT);
 263     }
 264     if(unlikely(!ff)) return 0;
 265
 266     ff = procfile_readall(ff);
 267     if(unlikely(!ff)) return 0; // we return 0, so that we will retry to open it next time
 268
 269     uint32_t lines = procfile_lines(ff), l;
 270
 271     for(l = 0; l < lines ;l++) {
 272         // --------------------------------------------------------------------------
 273         // Read parameters
 274
 275         char *disk;
 276         unsigned long       major = 0, minor = 0;
 277
 278         collected_number    reads = 0,  mreads = 0,  readsectors = 0,  readms = 0,
 279                             writes = 0, mwrites = 0, writesectors = 0, writems = 0,
 280                             queued_ios = 0, busy_ms = 0, backlog_ms = 0;
 281
 282         collected_number    last_reads = 0,  last_readsectors = 0,  last_readms = 0,
 283                             last_writes = 0, last_writesectors = 0, last_writems = 0,
 284                             last_busy_ms = 0;
 285
 286         uint32_t words = procfile_linewords(ff, l);
 287         if(unlikely(words < 14)) continue;
 288
 289         major           = strtoul(procfile_lineword(ff, l, 0), NULL, 10);
 290         minor           = strtoul(procfile_lineword(ff, l, 1), NULL, 10);
 291         disk            = procfile_lineword(ff, l, 2);
 292
 293         // # of reads completed # of writes completed
 294         // This is the total number of reads or writes completed successfully.
 295         reads           = strtoull(procfile_lineword(ff, l, 3), NULL, 10);  // rd_ios
 296         writes          = strtoull(procfile_lineword(ff, l, 7), NULL, 10);  // wr_ios
 297
 298         // # of reads merged # of writes merged
 299         // Reads and writes which are adjacent to each other may be merged for
 300         // efficiency.  Thus two 4K reads may become one 8K read before it is
 301         // ultimately handed to the disk, and so it will be counted (and queued)
 302         mreads          = strtoull(procfile_lineword(ff, l, 4), NULL, 10);  // rd_merges_or_rd_sec
 303         mwrites         = strtoull(procfile_lineword(ff, l, 8), NULL, 10);  // wr_merges
 304
 305         // # of sectors read # of sectors written
 306         // This is the total number of sectors read or written successfully.
 307         readsectors     = strtoull(procfile_lineword(ff, l, 5), NULL, 10);  // rd_sec_or_wr_ios
 308         writesectors    = strtoull(procfile_lineword(ff, l, 9), NULL, 10);  // wr_sec
 309
 310         // # of milliseconds spent reading # of milliseconds spent writing
 311         // This is the total number of milliseconds spent by all reads or writes (as
 312         // measured from __make_request() to end_that_request_last()).
 313         readms          = strtoull(procfile_lineword(ff, l, 6), NULL, 10);  // rd_ticks_or_wr_sec
 314         writems         = strtoull(procfile_lineword(ff, l, 10), NULL, 10); // wr_ticks
 315
 316         // # of I/Os currently in progress
 317         // The only field that should go to zero. Incremented as requests are
 318         // given to appropriate struct request_queue and decremented as they finish.
 319         queued_ios      = strtoull(procfile_lineword(ff, l, 11), NULL, 10); // ios_pgr
 320
 321         // # of milliseconds spent doing I/Os
 322         // This field increases so long as field queued_ios is nonzero.
 323         busy_ms         = strtoull(procfile_lineword(ff, l, 12), NULL, 10); // tot_ticks
 324
 325         // weighted # of milliseconds spent doing I/Os
 326         // This field is incremented at each I/O start, I/O completion, I/O
 327         // merge, or read of these stats by the number of I/Os in progress
 328         // (field queued_ios) times the number of milliseconds spent doing I/O since the
 329         // last update of this field.  This can provide an easy measure of both
 330         // I/O completion time and the backlog that may be accumulating.
 331         backlog_ms      = strtoull(procfile_lineword(ff, l, 13), NULL, 10); // rq_ticks
 332
 333
 334         // --------------------------------------------------------------------------
 335         // remove slashes from disk names
 336         char *s;
 337         for(s = disk; *s ;s++)
 338             if(*s == '/') *s = '_';
 339
 340         // --------------------------------------------------------------------------
 341         // get a disk structure for the disk
 342
 343         struct disk *d = get_disk(major, minor, disk);
 344
 345
 346         // --------------------------------------------------------------------------
 347         // Set its family based on mount point
 348
 349         char *family = d->mount_point;
 350         if(!family) family = disk;
 351
 352
 353         // --------------------------------------------------------------------------
 354         // Check the configuration for the device
 355
 356         if(unlikely(!d->configured)) {
 357             char var_name[4096 + 1];
 358             snprintfz(var_name, 4096, "plugin:proc:/proc/diskstats:%s", disk);
 359
 360             int def_enable = config_get_boolean_ondemand(var_name, "enable", global_enable_new_disks_detected_at_runtime);
 361             if(unlikely(def_enable == CONFIG_ONDEMAND_NO)) {
 362                 // the user does not want any metrics for this disk
 363                 d->do_io = CONFIG_ONDEMAND_NO;
 364                 d->do_ops = CONFIG_ONDEMAND_NO;
 365                 d->do_mops = CONFIG_ONDEMAND_NO;
 366                 d->do_iotime = CONFIG_ONDEMAND_NO;
 367                 d->do_qops = CONFIG_ONDEMAND_NO;
 368                 d->do_util = CONFIG_ONDEMAND_NO;
 369                 d->do_backlog = CONFIG_ONDEMAND_NO;
 370             }
 371             else {
 372                 // this disk is enabled
 373                 // check its direct settings
 374
 375                 int def_performance = CONFIG_ONDEMAND_ONDEMAND;
 376
 377                 // since this is 'on demand' we can figure the performance settings
 378                 // based on the type of disk
 379
 380                 switch(d->type) {
 381                     case DISK_TYPE_PHYSICAL:
 382                         def_performance = global_enable_performance_for_physical_disks;
 383                         break;
 384
 385                     case DISK_TYPE_PARTITION:
 386                         def_performance = global_enable_performance_for_partitions;
 387                         break;
 388
 389                     case DISK_TYPE_CONTAINER:
 390                         def_performance = global_enable_performance_for_virtual_disks;
 391                         break;
 392                 }
 393
 394                 // check if we have to disable performance for this disk
 395                 if(def_performance)
 396                     def_performance = is_major_enabled((int)major);
 397
 398                 // ------------------------------------------------------------
 399                 // now we have def_performance and def_space
 400                 // to work further
 401
 402                 // def_performance
 403                 // check the user configuration (this will also show our 'on demand' decision)
 404                 def_performance = config_get_boolean_ondemand(var_name, "enable performance metrics", def_performance);
 405
 406                 int ddo_io = CONFIG_ONDEMAND_NO,
 407                     ddo_ops = CONFIG_ONDEMAND_NO,
 408                     ddo_mops = CONFIG_ONDEMAND_NO,
 409                     ddo_iotime = CONFIG_ONDEMAND_NO,
 410                     ddo_qops = CONFIG_ONDEMAND_NO,
 411                     ddo_util = CONFIG_ONDEMAND_NO,
 412                     ddo_backlog = CONFIG_ONDEMAND_NO;
 413
 414                 // we enable individual performance charts only when def_performance is not disabled
 415                 if(unlikely(def_performance != CONFIG_ONDEMAND_NO)) {
 416                     ddo_io = global_do_io,
 417                     ddo_ops = global_do_ops,
 418                     ddo_mops = global_do_mops,
 419                     ddo_iotime = global_do_iotime,
 420                     ddo_qops = global_do_qops,
 421                     ddo_util = global_do_util,
 422                     ddo_backlog = global_do_backlog;
 423                 }
 424
 425                 d->do_io      = config_get_boolean_ondemand(var_name, "bandwidth", ddo_io);
 426                 d->do_ops     = config_get_boolean_ondemand(var_name, "operations", ddo_ops);
 427                 d->do_mops    = config_get_boolean_ondemand(var_name, "merged operations", ddo_mops);
 428                 d->do_iotime  = config_get_boolean_ondemand(var_name, "i/o time", ddo_iotime);
 429                 d->do_qops    = config_get_boolean_ondemand(var_name, "queued operations", ddo_qops);
 430                 d->do_util    = config_get_boolean_ondemand(var_name, "utilization percentage", ddo_util);
 431                 d->do_backlog = config_get_boolean_ondemand(var_name, "backlog", ddo_backlog);
 432             }
 433
 434             d->configured = 1;
 435         }
 436
 437         RRDSET *st;
 438
 439         // --------------------------------------------------------------------------
 440         // Do performance metrics
 441
 442         if(d->do_io == CONFIG_ONDEMAND_YES || (d->do_io == CONFIG_ONDEMAND_ONDEMAND && (readsectors || writesectors))) {
 443             d->do_io = CONFIG_ONDEMAND_YES;
 444
 445             st = rrdset_find_bytype(RRD_TYPE_DISK, disk);
 446             if(unlikely(!st)) {
 447                 st = rrdset_create(RRD_TYPE_DISK, disk, NULL, family, "disk.io", "Disk I/O Bandwidth", "kilobytes/s", 2000, update_every, RRDSET_TYPE_AREA);
 448
 449                 rrddim_add(st, "reads", NULL, d->sector_size, 1024, RRDDIM_INCREMENTAL);
 450                 rrddim_add(st, "writes", NULL, d->sector_size * -1, 1024, RRDDIM_INCREMENTAL);
 451             }
 452             else rrdset_next(st);
 453
 454             last_readsectors  = rrddim_set(st, "reads", readsectors);
 455             last_writesectors = rrddim_set(st, "writes", writesectors);
 456             rrdset_done(st);
 457         }
 458
 459         // --------------------------------------------------------------------
 460
 461         if(d->do_ops == CONFIG_ONDEMAND_YES || (d->do_ops == CONFIG_ONDEMAND_ONDEMAND && (reads || writes))) {
 462             d->do_ops = CONFIG_ONDEMAND_YES;
 463
 464             st = rrdset_find_bytype("disk_ops", disk);
 465             if(unlikely(!st)) {
 466                 st = rrdset_create("disk_ops", disk, NULL, family, "disk.ops", "Disk Completed I/O Operations", "operations/s", 2001, update_every, RRDSET_TYPE_LINE);
 467                 st->isdetail = 1;
 468
 469                 rrddim_add(st, "reads", NULL, 1, 1, RRDDIM_INCREMENTAL);
 470                 rrddim_add(st, "writes", NULL, -1, 1, RRDDIM_INCREMENTAL);
 471             }
 472             else rrdset_next(st);
 473
 474             last_reads  = rrddim_set(st, "reads", reads);
 475             last_writes = rrddim_set(st, "writes", writes);
 476             rrdset_done(st);
 477         }
 478
 479         // --------------------------------------------------------------------
 480
 481         if(d->do_qops == CONFIG_ONDEMAND_YES || (d->do_qops == CONFIG_ONDEMAND_ONDEMAND && queued_ios)) {
 482             d->do_qops = CONFIG_ONDEMAND_YES;
 483
 484             st = rrdset_find_bytype("disk_qops", disk);
 485             if(unlikely(!st)) {
 486                 st = rrdset_create("disk_qops", disk, NULL, family, "disk.qops", "Disk Current I/O Operations", "operations", 2002, update_every, RRDSET_TYPE_LINE);
 487                 st->isdetail = 1;
 488
 489                 rrddim_add(st, "operations", NULL, 1, 1, RRDDIM_ABSOLUTE);
 490             }
 491             else rrdset_next(st);
 492
 493             rrddim_set(st, "operations", queued_ios);
 494             rrdset_done(st);
 495         }
 496
 497         // --------------------------------------------------------------------
 498
 499         if(d->do_backlog == CONFIG_ONDEMAND_YES || (d->do_backlog == CONFIG_ONDEMAND_ONDEMAND && backlog_ms)) {
 500             d->do_backlog = CONFIG_ONDEMAND_YES;
 501
 502             st = rrdset_find_bytype("disk_backlog", disk);
 503             if(unlikely(!st)) {
 504                 st = rrdset_create("disk_backlog", disk, NULL, family, "disk.backlog", "Disk Backlog", "backlog (ms)", 2003, update_every, RRDSET_TYPE_AREA);
 505                 st->isdetail = 1;
 506
 507                 rrddim_add(st, "backlog", NULL, 1, 10, RRDDIM_INCREMENTAL);
 508             }
 509             else rrdset_next(st);
 510
 511             rrddim_set(st, "backlog", backlog_ms);
 512             rrdset_done(st);
 513         }
 514
 515         // --------------------------------------------------------------------
 516
 517         if(d->do_util == CONFIG_ONDEMAND_YES || (d->do_util == CONFIG_ONDEMAND_ONDEMAND && busy_ms)) {
 518             d->do_util = CONFIG_ONDEMAND_YES;
 519
 520             st = rrdset_find_bytype("disk_util", disk);
 521             if(unlikely(!st)) {
 522                 st = rrdset_create("disk_util", disk, NULL, family, "disk.util", "Disk Utilization Time", "% of time working", 2004, update_every, RRDSET_TYPE_AREA);
 523                 st->isdetail = 1;
 524
 525                 rrddim_add(st, "utilization", NULL, 1, 10, RRDDIM_INCREMENTAL);
 526             }
 527             else rrdset_next(st);
 528
 529             last_busy_ms = rrddim_set(st, "utilization", busy_ms);
 530             rrdset_done(st);
 531         }
 532
 533         // --------------------------------------------------------------------
 534
 535         if(d->do_mops == CONFIG_ONDEMAND_YES || (d->do_mops == CONFIG_ONDEMAND_ONDEMAND && (mreads || mwrites))) {
 536             d->do_mops = CONFIG_ONDEMAND_YES;
 537
 538             st = rrdset_find_bytype("disk_mops", disk);
 539             if(unlikely(!st)) {
 540                 st = rrdset_create("disk_mops", disk, NULL, family, "disk.mops", "Disk Merged Operations", "merged operations/s", 2021, update_every, RRDSET_TYPE_LINE);
 541                 st->isdetail = 1;
 542
 543                 rrddim_add(st, "reads", NULL, 1, 1, RRDDIM_INCREMENTAL);
 544                 rrddim_add(st, "writes", NULL, -1, 1, RRDDIM_INCREMENTAL);
 545             }
 546             else rrdset_next(st);
 547
 548             rrddim_set(st, "reads", mreads);
 549             rrddim_set(st, "writes", mwrites);
 550             rrdset_done(st);
 551         }
 552
 553         // --------------------------------------------------------------------
 554
 555         if(d->do_iotime == CONFIG_ONDEMAND_YES || (d->do_iotime == CONFIG_ONDEMAND_ONDEMAND && (readms || writems))) {
 556             d->do_iotime = CONFIG_ONDEMAND_YES;
 557
 558             st = rrdset_find_bytype("disk_iotime", disk);
 559             if(unlikely(!st)) {
 560                 st = rrdset_create("disk_iotime", disk, NULL, family, "disk.iotime", "Disk Total I/O Time", "milliseconds/s", 2022, update_every, RRDSET_TYPE_LINE);
 561                 st->isdetail = 1;
 562
 563                 rrddim_add(st, "reads", NULL, 1, 1, RRDDIM_INCREMENTAL);
 564                 rrddim_add(st, "writes", NULL, -1, 1, RRDDIM_INCREMENTAL);
 565             }
 566             else rrdset_next(st);
 567
 568             last_readms  = rrddim_set(st, "reads", readms);
 569             last_writems = rrddim_set(st, "writes", writems);
 570             rrdset_done(st);
 571         }
 572
 573         // --------------------------------------------------------------------
 574         // calculate differential charts
 575         // only if this is not the first time we run
 576
 577         if(likely(dt)) {
 578             if( (d->do_iotime == CONFIG_ONDEMAND_YES || (d->do_iotime == CONFIG_ONDEMAND_ONDEMAND && (readms || writems))) &&
 579                 (d->do_ops    == CONFIG_ONDEMAND_YES || (d->do_ops    == CONFIG_ONDEMAND_ONDEMAND && (reads || writes)))) {
 580                 st = rrdset_find_bytype("disk_await", disk);
 581                 if(unlikely(!st)) {
 582                     st = rrdset_create("disk_await", disk, NULL, family, "disk.await", "Average Completed I/O Operation Time", "ms per operation", 2005, update_every, RRDSET_TYPE_LINE);
 583                     st->isdetail = 1;
 584
 585                     rrddim_add(st, "reads", NULL, 1, 1, RRDDIM_ABSOLUTE);
 586                     rrddim_add(st, "writes", NULL, -1, 1, RRDDIM_ABSOLUTE);
 587                 }
 588                 else rrdset_next(st);
 589
 590                 rrddim_set(st, "reads", (reads - last_reads) ? (readms - last_readms) / (reads - last_reads) : 0);
 591                 rrddim_set(st, "writes", (writes - last_writes) ? (writems - last_writems) / (writes - last_writes) : 0);
 592                 rrdset_done(st);
 593             }
 594
 595             if( (d->do_io  == CONFIG_ONDEMAND_YES || (d->do_io  == CONFIG_ONDEMAND_ONDEMAND && (readsectors || writesectors))) &&
 596                 (d->do_ops == CONFIG_ONDEMAND_YES || (d->do_ops == CONFIG_ONDEMAND_ONDEMAND && (reads || writes)))) {
 597                 st = rrdset_find_bytype("disk_avgsz", disk);
 598                 if(unlikely(!st)) {
 599                     st = rrdset_create("disk_avgsz", disk, NULL, family, "disk.avgsz", "Average Completed I/O Operation Bandwidth", "kilobytes per operation", 2006, update_every, RRDSET_TYPE_AREA);
 600                     st->isdetail = 1;
 601
 602                     rrddim_add(st, "reads", NULL, d->sector_size, 1024, RRDDIM_ABSOLUTE);
 603                     rrddim_add(st, "writes", NULL, d->sector_size * -1, 1024, RRDDIM_ABSOLUTE);
 604                 }
 605                 else rrdset_next(st);
 606
 607                 rrddim_set(st, "reads", (reads - last_reads) ? (readsectors - last_readsectors) / (reads - last_reads) : 0);
 608                 rrddim_set(st, "writes", (writes - last_writes) ? (writesectors - last_writesectors) / (writes - last_writes) : 0);
 609                 rrdset_done(st);
 610             }
 611
 612             if( (d->do_util == CONFIG_ONDEMAND_YES || (d->do_util == CONFIG_ONDEMAND_ONDEMAND && busy_ms)) &&
 613                 (d->do_ops  == CONFIG_ONDEMAND_YES || (d->do_ops  == CONFIG_ONDEMAND_ONDEMAND && (reads || writes)))) {
 614                 st = rrdset_find_bytype("disk_svctm", disk);
 615                 if(unlikely(!st)) {
 616                     st = rrdset_create("disk_svctm", disk, NULL, family, "disk.svctm", "Average Service Time", "ms per operation", 2007, update_every, RRDSET_TYPE_LINE);
 617                     st->isdetail = 1;
 618
 619                     rrddim_add(st, "svctm", NULL, 1, 1, RRDDIM_ABSOLUTE);
 620                 }
 621                 else rrdset_next(st);
 622
 623                 rrddim_set(st, "svctm", ((reads - last_reads) + (writes - last_writes)) ? (busy_ms - last_busy_ms) / ((reads - last_reads) + (writes - last_writes)) : 0);
 624                 rrdset_done(st);
 625             }
 626         }
 627     }
 628
 629     return 0;
 630 }