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