src/proc_diskstats.c

   1 #ifdef HAVE_CONFIG_H
   2 #include <config.h>
   3 #endif
   4 #include <dirent.h>
   5 #include <fcntl.h>
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <string.h>
   9 #include <sys/stat.h>
  10 #include <sys/statvfs.h>
  11 #include <sys/types.h>
  12 #include <unistd.h>
  13
  14
  15 #include "common.h"
  16 #include "log.h"
  17 #include "appconfig.h"
  18 #include "procfile.h"
  19 #include "rrd.h"
  20 #include "plugin_proc.h"
  21
  22 #include "proc_self_mountinfo.h"
  23
  24 #define RRD_TYPE_DISK "disk"
  25
  26 #define DISK_TYPE_PHYSICAL  1
  27 #define DISK_TYPE_PARTITION 2
  28 #define DISK_TYPE_CONTAINER 3
  29
  30 struct disk {
  31         unsigned long major;
  32         unsigned long minor;
  33         int type;
  34         char *mount_point;
  35         struct disk *next;
  36 } *disk_root = NULL;
  37
  38 struct disk *get_disk(unsigned long major, unsigned long minor) {
  39         static char path_find_block_device[FILENAME_MAX + 1] = "";
  40         static struct mountinfo *mountinfo_root = NULL;
  41         struct disk *d;
  42
  43         // search for it in our RAM list.
  44         // this is sequential, but since we just walk through
  45         // and the number of disks / partitions in a system
  46         // should not be that many, it should be acceptable
  47         for(d = disk_root; d ; d = d->next)
  48                 if(unlikely(d->major == major && d->minor == minor))
  49                         break;
  50
  51         // if we found it, return it
  52         if(likely(d))
  53                 return d;
  54
  55         if(unlikely(!path_find_block_device[0])) {
  56                 char dirname[FILENAME_MAX + 1];
  57                 snprintfz(dirname, FILENAME_MAX, "%s%s", global_host_prefix, "/sys/dev/block/%lu:%lu/%s");
  58                 snprintfz(path_find_block_device, FILENAME_MAX, "%s", config_get("plugin:proc:/proc/diskstats", "path to get block device infos", dirname));
  59         }
  60
  61         // not found
  62         // create a new disk structure
  63         d = (struct disk *)malloc(sizeof(struct disk));
  64         if(!d) fatal("Cannot allocate memory for struct disk in proc_diskstats.");
  65
  66         d->major = major;
  67         d->minor = minor;
  68         d->type = DISK_TYPE_PHYSICAL; // Default type. Changed later if not correct.
  69         d->next = NULL;
  70
  71         // append it to the list
  72         if(!disk_root)
  73                 disk_root = d;
  74         else {
  75                 struct disk *last;
  76                 for(last = disk_root; last->next ;last = last->next);
  77                 last->next = d;
  78         }
  79
  80         // ------------------------------------------------------------------------
  81         // find the type of the device
  82
  83         // find if it is a partition
  84         // by checking if /sys/dev/block/MAJOR:MINOR/partition is readable.
  85         char buffer[FILENAME_MAX + 1];
  86         snprintfz(buffer, FILENAME_MAX, path_find_block_device, major, minor, "partition");
  87         if(access(buffer, R_OK) == 0) {
  88                 d->type = DISK_TYPE_PARTITION;
  89         } else {
  90                 // find if it is a container
  91                 // by checking if /sys/dev/block/MAJOR:MINOR/slaves has entries
  92                 snprintfz(buffer, FILENAME_MAX, path_find_block_device, major, minor, "slaves/");
  93                 DIR *dirp = opendir(buffer);
  94                 if (dirp != NULL) {
  95                 struct dirent *dp;
  96                         while( (dp = readdir(dirp)) ) {
  97                                 // . and .. are also files in empty folders.
  98                                 if(strcmp(dp->d_name, ".") == 0 || strcmp(dp->d_name, "..") == 0) {
  99                                         continue;
 100                                 }
 101                                 d->type = DISK_TYPE_CONTAINER;
 102                                 // Stop the loop after we found one file.
 103                                 break;
 104                         }
 105                         if(closedir(dirp) == -1)
 106                                 error("Unable to close dir %s", buffer);
 107                 }
 108         }
 109
 110         // ------------------------------------------------------------------------
 111         // check if we can find its mount point
 112
 113         // mountinfo_find() can be called with NULL mountinfo_root
 114         struct mountinfo *mi = mountinfo_find(mountinfo_root, d->major, d->minor);
 115         if(unlikely(!mi)) {
 116                 // mountinfo_free() can be called with NULL mountinfo_root
 117                 mountinfo_free(mountinfo_root);
 118
 119                 // re-read mountinfo in case something changed
 120                 mountinfo_root = mountinfo_read();
 121
 122                 // search again for this disk
 123                 mi = mountinfo_find(mountinfo_root, d->major, d->minor);
 124         }
 125
 126         if(mi)
 127                 d->mount_point = strdup(mi->mount_point);
 128                 // no need to check for NULL
 129         else
 130                 d->mount_point = NULL;
 131
 132         return d;
 133 }
 134
 135 int do_proc_diskstats(int update_every, unsigned long long dt) {
 136         static procfile *ff = NULL;
 137         static char path_to_get_hw_sector_size[FILENAME_MAX + 1] = "";
 138         static int enable_autodetection;
 139         static int enable_physical_disks, enable_virtual_disks, enable_partitions, enable_mountpoints, enable_virtual_mountpoints, enable_space_metrics;
 140         static int do_io, do_ops, do_mops, do_iotime, do_qops, do_util, do_backlog, do_space, do_inodes;
 141         static struct statvfs buff_statvfs;
 142         static struct stat buff_stat;
 143
 144         enable_autodetection = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "enable new disks detected at runtime", CONFIG_ONDEMAND_ONDEMAND);
 145
 146         enable_physical_disks = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "performance metrics for physical disks", CONFIG_ONDEMAND_ONDEMAND);
 147         enable_virtual_disks = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "performance metrics for virtual disks", CONFIG_ONDEMAND_NO);
 148         enable_partitions = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "performance metrics for partitions", CONFIG_ONDEMAND_NO);
 149         enable_mountpoints = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "performance metrics for mounted filesystems", CONFIG_ONDEMAND_NO);
 150         enable_virtual_mountpoints = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "performance metrics for mounted virtual disks", CONFIG_ONDEMAND_ONDEMAND);
 151         enable_space_metrics = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "space metrics for mounted filesystems", CONFIG_ONDEMAND_ONDEMAND);
 152
 153         do_io      = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "bandwidth for all disks", CONFIG_ONDEMAND_ONDEMAND);
 154         do_ops     = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "operations for all disks", CONFIG_ONDEMAND_ONDEMAND);
 155         do_mops    = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "merged operations for all disks", CONFIG_ONDEMAND_ONDEMAND);
 156         do_iotime  = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "i/o time for all disks", CONFIG_ONDEMAND_ONDEMAND);
 157         do_qops    = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "queued operations for all disks", CONFIG_ONDEMAND_ONDEMAND);
 158         do_util    = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "utilization percentage for all disks", CONFIG_ONDEMAND_ONDEMAND);
 159         do_backlog = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "backlog for all disks", CONFIG_ONDEMAND_ONDEMAND);
 160         do_space   = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "space usage for all disks", CONFIG_ONDEMAND_ONDEMAND);
 161         do_inodes  = config_get_boolean_ondemand("plugin:proc:/proc/diskstats", "inodes usage for all disks", CONFIG_ONDEMAND_ONDEMAND);
 162
 163         if(!ff) {
 164                 char filename[FILENAME_MAX + 1];
 165                 snprintfz(filename, FILENAME_MAX, "%s%s", global_host_prefix, "/proc/diskstats");
 166                 ff = procfile_open(config_get("plugin:proc:/proc/diskstats", "filename to monitor", filename), " \t", PROCFILE_FLAG_DEFAULT);
 167         }
 168         if(!ff) return 1;
 169
 170         if(!path_to_get_hw_sector_size[0]) {
 171                 char filename[FILENAME_MAX + 1];
 172                 snprintfz(filename, FILENAME_MAX, "%s%s", global_host_prefix, "/sys/block/%s/queue/hw_sector_size");
 173                 snprintfz(path_to_get_hw_sector_size, FILENAME_MAX, "%s", config_get("plugin:proc:/proc/diskstats", "path to get h/w sector size", filename));
 174         }
 175
 176         ff = procfile_readall(ff);
 177         if(!ff) return 0; // we return 0, so that we will retry to open it next time
 178
 179         uint32_t lines = procfile_lines(ff), l;
 180         uint32_t words;
 181
 182         for(l = 0; l < lines ;l++) {
 183                 // --------------------------------------------------------------------------
 184                 // Read parameters
 185                 char *disk;
 186                 unsigned long long      major = 0, minor = 0,
 187                                                         reads = 0,  mreads = 0,  readsectors = 0,  readms = 0,
 188                                                         writes = 0, mwrites = 0, writesectors = 0, writems = 0,
 189                                                         queued_ios = 0, busy_ms = 0, backlog_ms = 0,
 190                                                         space_avail = 0, space_avail_root = 0, space_used = 0,
 191                                                         inodes_avail = 0, inodes_avail_root = 0, inodes_used = 0;
 192
 193                 unsigned long long      last_reads = 0,  last_readsectors = 0,  last_readms = 0,
 194                                                         last_writes = 0, last_writesectors = 0, last_writems = 0,
 195                                                         last_busy_ms = 0;
 196
 197                 words = procfile_linewords(ff, l);
 198                 if(words < 14) continue;
 199
 200                 major                   = strtoull(procfile_lineword(ff, l, 0), NULL, 10);
 201                 minor                   = strtoull(procfile_lineword(ff, l, 1), NULL, 10);
 202                 disk                    = procfile_lineword(ff, l, 2);
 203
 204                 // # of reads completed # of writes completed
 205                 // This is the total number of reads or writes completed successfully.
 206                 reads                   = strtoull(procfile_lineword(ff, l, 3), NULL, 10);      // rd_ios
 207                 writes                  = strtoull(procfile_lineword(ff, l, 7), NULL, 10);      // wr_ios
 208
 209                 // # of reads merged # of writes merged
 210                 // Reads and writes which are adjacent to each other may be merged for
 211             // efficiency.  Thus two 4K reads may become one 8K read before it is
 212             // ultimately handed to the disk, and so it will be counted (and queued)
 213                 mreads                  = strtoull(procfile_lineword(ff, l, 4), NULL, 10);      // rd_merges_or_rd_sec
 214                 mwrites                 = strtoull(procfile_lineword(ff, l, 8), NULL, 10);      // wr_merges
 215
 216                 // # of sectors read # of sectors written
 217                 // This is the total number of sectors read or written successfully.
 218                 readsectors     = strtoull(procfile_lineword(ff, l, 5), NULL, 10);      // rd_sec_or_wr_ios
 219                 writesectors    = strtoull(procfile_lineword(ff, l, 9), NULL, 10);      // wr_sec
 220
 221                 // # of milliseconds spent reading # of milliseconds spent writing
 222                 // This is the total number of milliseconds spent by all reads or writes (as
 223                 // measured from __make_request() to end_that_request_last()).
 224                 readms                  = strtoull(procfile_lineword(ff, l, 6), NULL, 10);      // rd_ticks_or_wr_sec
 225                 writems                 = strtoull(procfile_lineword(ff, l, 10), NULL, 10);     // wr_ticks
 226
 227                 // # of I/Os currently in progress
 228                 // The only field that should go to zero. Incremented as requests are
 229                 // given to appropriate struct request_queue and decremented as they finish.
 230                 queued_ios              = strtoull(procfile_lineword(ff, l, 11), NULL, 10);     // ios_pgr
 231
 232                 // # of milliseconds spent doing I/Os
 233                 // This field increases so long as field queued_ios is nonzero.
 234                 busy_ms                 = strtoull(procfile_lineword(ff, l, 12), NULL, 10);     // tot_ticks
 235
 236                 // weighted # of milliseconds spent doing I/Os
 237                 // This field is incremented at each I/O start, I/O completion, I/O
 238                 // merge, or read of these stats by the number of I/Os in progress
 239                 // (field queued_ios) times the number of milliseconds spent doing I/O since the
 240                 // last update of this field.  This can provide an easy measure of both
 241                 // I/O completion time and the backlog that may be accumulating.
 242                 backlog_ms              = strtoull(procfile_lineword(ff, l, 13), NULL, 10);     // rq_ticks
 243
 244                 // --------------------------------------------------------------------------
 245                 // remove slashes from disk names
 246                 char *s;
 247                 for(s = disk; *s ;s++) if(*s == '/') *s = '_';
 248                 struct disk *d = get_disk(major, minor);
 249                 // Find mount point and family
 250                 char *mount_point = d->mount_point;
 251                 char *family = d->mount_point;
 252                 if(!family) family = disk;
 253
 254                 // --------------------------------------------------------------------------
 255                 // Check if device is enabled by autodetection or config
 256                 int def_enable = -1;
 257                 char var_name[4096 + 1];
 258                 snprintfz(var_name, 4096, "plugin:proc:/proc/diskstats:%s", disk);
 259
 260                 if(def_enable == -1) def_enable = config_get_boolean_ondemand(var_name, "enable", CONFIG_ONDEMAND_ONDEMAND);
 261                 if(def_enable == CONFIG_ONDEMAND_NO) continue;
 262
 263                 int def_performance = CONFIG_ONDEMAND_NO, def_space = CONFIG_ONDEMAND_NO;
 264                 if(enable_autodetection)  {
 265                         if(enable_physical_disks && (d->type == DISK_TYPE_PHYSICAL)) {
 266                                 def_performance = enable_physical_disks;
 267                         } else if(enable_virtual_disks && (d->type == DISK_TYPE_CONTAINER)) {
 268                                 def_performance = enable_virtual_disks;
 269                         } else if(enable_partitions && (d->type == DISK_TYPE_PARTITION)) {
 270                                 def_performance = enable_partitions;
 271                         } else if(enable_virtual_mountpoints && (d->type == DISK_TYPE_CONTAINER) && (d->mount_point != NULL)) {
 272                                 def_performance = enable_virtual_mountpoints;
 273                         } else if(enable_mountpoints && (d->mount_point != NULL)) {
 274                                 def_performance = enable_mountpoints;
 275                         }
 276
 277                         if(enable_space_metrics && (d->mount_point != NULL)) {
 278                                 def_space = enable_space_metrics;
 279                         }
 280                 }
 281
 282                 RRDSET *st;
 283
 284                 // --------------------------------------------------------------------------
 285                 // Do performance metrics
 286                 def_performance = config_get_boolean_ondemand(var_name, "enable performance metrics", def_performance);
 287                 if( (def_performance == CONFIG_ONDEMAND_YES) || (def_performance == CONFIG_ONDEMAND_ONDEMAND && reads && writes) ) {
 288                         int ddo_io = do_io, ddo_ops = do_ops, ddo_mops = do_mops, ddo_iotime = do_iotime, ddo_qops = do_qops, ddo_util = do_util, ddo_backlog = do_backlog;
 289
 290                         ddo_io          = config_get_boolean_ondemand(var_name, "bandwidth", ddo_io);
 291                         ddo_ops         = config_get_boolean_ondemand(var_name, "operations", ddo_ops);
 292                         ddo_mops        = config_get_boolean_ondemand(var_name, "merged operations", ddo_mops);
 293                         ddo_iotime      = config_get_boolean_ondemand(var_name, "i/o time", ddo_iotime);
 294                         ddo_qops        = config_get_boolean_ondemand(var_name, "queued operations", ddo_qops);
 295                         ddo_util        = config_get_boolean_ondemand(var_name, "utilization percentage", ddo_util);
 296                         ddo_backlog = config_get_boolean_ondemand(var_name, "backlog", ddo_backlog);
 297
 298                         // by default, do not add charts that do not have values
 299                         if(ddo_io == CONFIG_ONDEMAND_ONDEMAND && !reads && !writes) ddo_io = 0;
 300                         if(ddo_mops == CONFIG_ONDEMAND_ONDEMAND && mreads == 0 && mwrites == 0) ddo_mops = 0;
 301                         if(ddo_iotime == CONFIG_ONDEMAND_ONDEMAND && readms == 0 && writems == 0) ddo_iotime = 0;
 302                         if(ddo_util == CONFIG_ONDEMAND_ONDEMAND && busy_ms == 0) ddo_util = 0;
 303                         if(ddo_backlog == CONFIG_ONDEMAND_ONDEMAND && backlog_ms == 0) ddo_backlog = 0;
 304                         if(ddo_qops == CONFIG_ONDEMAND_ONDEMAND && backlog_ms == 0) ddo_qops = 0;
 305
 306                         // for absolute values, we need to switch the setting to 'yes'
 307                         // to allow it refresh from now on
 308                         if(ddo_qops == CONFIG_ONDEMAND_ONDEMAND) config_set(var_name, "queued operations", "yes");
 309
 310                         // --------------------------------------------------------------------
 311                         int sector_size = 512;
 312                         if(ddo_io) {
 313                                 st = rrdset_find_bytype(RRD_TYPE_DISK, disk);
 314                                 if(!st) {
 315                                         char tf[FILENAME_MAX + 1], *t;
 316                                         char ssfilename[FILENAME_MAX + 1];
 317
 318                                         strncpyz(tf, disk, FILENAME_MAX);
 319
 320                                         // replace all / with !
 321                                         while((t = strchr(tf, '/'))) *t = '!';
 322
 323                                         snprintfz(ssfilename, FILENAME_MAX, path_to_get_hw_sector_size, tf);
 324                                         FILE *fpss = fopen(ssfilename, "r");
 325                                         if(fpss) {
 326                                                 char ssbuffer[1025];
 327                                                 char *tmp = fgets(ssbuffer, 1024, fpss);
 328
 329                                                 if(tmp) {
 330                                                         sector_size = atoi(tmp);
 331                                                         if(sector_size <= 0) {
 332                                                                 error("Invalid sector size %d for device %s in %s. Assuming 512.", sector_size, disk, ssfilename);
 333                                                                 sector_size = 512;
 334                                                         }
 335                                                 }
 336                                                 else error("Cannot read data for sector size for device %s from %s. Assuming 512.", disk, ssfilename);
 337
 338                                                 fclose(fpss);
 339                                         }
 340                                         else error("Cannot read sector size for device %s from %s. Assuming 512.", disk, ssfilename);
 341
 342                                         st = rrdset_create(RRD_TYPE_DISK, disk, NULL, family, "disk.io", "Disk I/O Bandwidth", "kilobytes/s", 2000, update_every, RRDSET_TYPE_AREA);
 343
 344                                         rrddim_add(st, "reads", NULL, sector_size, 1024, RRDDIM_INCREMENTAL);
 345                                         rrddim_add(st, "writes", NULL, sector_size * -1, 1024, RRDDIM_INCREMENTAL);
 346                                 }
 347                                 else rrdset_next_usec(st, dt);
 348
 349                                 last_readsectors  = rrddim_set(st, "reads", readsectors);
 350                                 last_writesectors = rrddim_set(st, "writes", writesectors);
 351                                 rrdset_done(st);
 352                         }
 353
 354                         // --------------------------------------------------------------------
 355                         if(ddo_ops) {
 356                                 st = rrdset_find_bytype("disk_ops", disk);
 357                                 if(!st) {
 358                                         st = rrdset_create("disk_ops", disk, NULL, family, "disk.ops", "Disk Completed I/O Operations", "operations/s", 2001, update_every, RRDSET_TYPE_LINE);
 359                                         st->isdetail = 1;
 360
 361                                         rrddim_add(st, "reads", NULL, 1, 1, RRDDIM_INCREMENTAL);
 362                                         rrddim_add(st, "writes", NULL, -1, 1, RRDDIM_INCREMENTAL);
 363                                 }
 364                                 else rrdset_next_usec(st, dt);
 365
 366                                 last_reads  = rrddim_set(st, "reads", reads);
 367                                 last_writes = rrddim_set(st, "writes", writes);
 368                                 rrdset_done(st);
 369                         }
 370
 371                         // --------------------------------------------------------------------
 372                         if(ddo_qops) {
 373                                 st = rrdset_find_bytype("disk_qops", disk);
 374                                 if(!st) {
 375                                         st = rrdset_create("disk_qops", disk, NULL, family, "disk.qops", "Disk Current I/O Operations", "operations", 2002, update_every, RRDSET_TYPE_LINE);
 376                                         st->isdetail = 1;
 377
 378                                         rrddim_add(st, "operations", NULL, 1, 1, RRDDIM_ABSOLUTE);
 379                                 }
 380                                 else rrdset_next_usec(st, dt);
 381
 382                                 rrddim_set(st, "operations", queued_ios);
 383                                 rrdset_done(st);
 384                         }
 385
 386                         // --------------------------------------------------------------------
 387                         if(ddo_backlog) {
 388                                 st = rrdset_find_bytype("disk_backlog", disk);
 389                                 if(!st) {
 390                                         st = rrdset_create("disk_backlog", disk, NULL, family, "disk.backlog", "Disk Backlog", "backlog (ms)", 2003, update_every, RRDSET_TYPE_AREA);
 391                                         st->isdetail = 1;
 392
 393                                         rrddim_add(st, "backlog", NULL, 1, 10, RRDDIM_INCREMENTAL);
 394                                 }
 395                                 else rrdset_next_usec(st, dt);
 396
 397                                 rrddim_set(st, "backlog", backlog_ms);
 398                                 rrdset_done(st);
 399                         }
 400
 401                         // --------------------------------------------------------------------
 402                         if(ddo_util) {
 403                                 st = rrdset_find_bytype("disk_util", disk);
 404                                 if(!st) {
 405                                         st = rrdset_create("disk_util", disk, NULL, family, "disk.util", "Disk Utilization Time", "% of time working", 2004, update_every, RRDSET_TYPE_AREA);
 406                                         st->isdetail = 1;
 407
 408                                         rrddim_add(st, "utilization", NULL, 1, 10, RRDDIM_INCREMENTAL);
 409                                 }
 410                                 else rrdset_next_usec(st, dt);
 411
 412                                 last_busy_ms = rrddim_set(st, "utilization", busy_ms);
 413                                 rrdset_done(st);
 414                         }
 415
 416                         // --------------------------------------------------------------------
 417                         if(ddo_mops) {
 418                                 st = rrdset_find_bytype("disk_mops", disk);
 419                                 if(!st) {
 420                                         st = rrdset_create("disk_mops", disk, NULL, family, "disk.mops", "Disk Merged Operations", "merged operations/s", 2021, update_every, RRDSET_TYPE_LINE);
 421                                         st->isdetail = 1;
 422
 423                                         rrddim_add(st, "reads", NULL, 1, 1, RRDDIM_INCREMENTAL);
 424                                         rrddim_add(st, "writes", NULL, -1, 1, RRDDIM_INCREMENTAL);
 425                                 }
 426                                 else rrdset_next_usec(st, dt);
 427
 428                                 rrddim_set(st, "reads", mreads);
 429                                 rrddim_set(st, "writes", mwrites);
 430                                 rrdset_done(st);
 431                         }
 432
 433                         // --------------------------------------------------------------------
 434                         if(ddo_iotime) {
 435                                 st = rrdset_find_bytype("disk_iotime", disk);
 436                                 if(!st) {
 437                                         st = rrdset_create("disk_iotime", disk, NULL, family, "disk.iotime", "Disk Total I/O Time", "milliseconds/s", 2022, update_every, RRDSET_TYPE_LINE);
 438                                         st->isdetail = 1;
 439
 440                                         rrddim_add(st, "reads", NULL, 1, 1, RRDDIM_INCREMENTAL);
 441                                         rrddim_add(st, "writes", NULL, -1, 1, RRDDIM_INCREMENTAL);
 442                                 }
 443                                 else rrdset_next_usec(st, dt);
 444
 445                                 last_readms  = rrddim_set(st, "reads", readms);
 446                                 last_writems = rrddim_set(st, "writes", writems);
 447                                 rrdset_done(st);
 448                         }
 449
 450                         // --------------------------------------------------------------------
 451                         // calculate differential charts
 452                         // only if this is not the first time we run
 453                         if(dt) {
 454                                 if(ddo_iotime && ddo_ops) {
 455                                         st = rrdset_find_bytype("disk_await", disk);
 456                                         if(!st) {
 457                                                 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);
 458                                                 st->isdetail = 1;
 459
 460                                                 rrddim_add(st, "reads", NULL, 1, 1, RRDDIM_ABSOLUTE);
 461                                                 rrddim_add(st, "writes", NULL, -1, 1, RRDDIM_ABSOLUTE);
 462                                         }
 463                                         else rrdset_next_usec(st, dt);
 464
 465                                         rrddim_set(st, "reads", (reads - last_reads) ? (readms - last_readms) / (reads - last_reads) : 0);
 466                                         rrddim_set(st, "writes", (writes - last_writes) ? (writems - last_writems) / (writes - last_writes) : 0);
 467                                         rrdset_done(st);
 468                                 }
 469
 470                                 if(ddo_io && ddo_ops) {
 471                                         st = rrdset_find_bytype("disk_avgsz", disk);
 472                                         if(!st) {
 473                                                 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);
 474                                                 st->isdetail = 1;
 475
 476                                                 rrddim_add(st, "reads", NULL, sector_size, 1024, RRDDIM_ABSOLUTE);
 477                                                 rrddim_add(st, "writes", NULL, -sector_size, 1024, RRDDIM_ABSOLUTE);
 478                                         }
 479                                         else rrdset_next_usec(st, dt);
 480
 481                                         rrddim_set(st, "reads", (reads - last_reads) ? (readsectors - last_readsectors) / (reads - last_reads) : 0);
 482                                         rrddim_set(st, "writes", (writes - last_writes) ? (writesectors - last_writesectors) / (writes - last_writes) : 0);
 483                                         rrdset_done(st);
 484                                 }
 485
 486                                 if(ddo_util && ddo_ops) {
 487                                         st = rrdset_find_bytype("disk_svctm", disk);
 488                                         if(!st) {
 489                                                 st = rrdset_create("disk_svctm", disk, NULL, family, "disk.svctm", "Average Service Time", "ms per operation", 2007, update_every, RRDSET_TYPE_LINE);
 490                                                 st->isdetail = 1;
 491
 492                                                 rrddim_add(st, "svctm", NULL, 1, 1, RRDDIM_ABSOLUTE);
 493                                         }
 494                                         else rrdset_next_usec(st, dt);
 495
 496                                         rrddim_set(st, "svctm", ((reads - last_reads) + (writes - last_writes)) ? (busy_ms - last_busy_ms) / ((reads - last_reads) + (writes - last_writes)) : 0);
 497                                         rrdset_done(st);
 498                                 }
 499                         }
 500                 }
 501
 502                 // --------------------------------------------------------------------------
 503                 // Do space metrics
 504                 def_space = config_get_boolean_ondemand(var_name, "enable space metrics", def_space);
 505                 if(def_space != CONFIG_ONDEMAND_NO) {
 506                         int ddo_space = do_space, ddo_inodes = do_inodes;
 507
 508                         ddo_space = config_get_boolean_ondemand(var_name, "space", ddo_space);
 509                         ddo_inodes = config_get_boolean_ondemand(var_name, "inodes", ddo_space);
 510                         if(mount_point && (ddo_space || ddo_inodes) ) {
 511                                 // collect space metrics using statvfs
 512                                 if (statvfs(mount_point, &buff_statvfs) < 0) {
 513                                         error("Failed checking disk space usage of %s", family);
 514                                 } else {
 515                                         // verify we collected the metrics for the right disk.
 516                                         // if not the mountpoint has changed.
 517                                         if(stat(mount_point, &buff_stat) == -1) {
 518                                                 error("Failed to call stat for %s", family);
 519                                         } else {
 520                                                 if(major(buff_stat.st_dev) == major && minor(buff_stat.st_dev) == minor)
 521                                                 {
 522                                                         if(ddo_space) {
 523                                                                 space_avail = buff_statvfs.f_bavail * buff_statvfs.f_bsize;
 524                                                                 space_avail_root = (buff_statvfs.f_bfree - buff_statvfs.f_bavail) * buff_statvfs.f_bsize;
 525                                                                 space_used = (buff_statvfs.f_blocks - buff_statvfs.f_bfree) * buff_statvfs.f_bsize;
 526
 527                                                                 st = rrdset_find_bytype("disk_space", disk);
 528                                                                 if(!st) {
 529                                                                         st = rrdset_create("disk_space", disk, NULL, family, "disk.space", "Disk Space Usage", "GB", 2023, update_every, RRDSET_TYPE_STACKED);
 530                                                                         st->isdetail = 1;
 531
 532                                                                         rrddim_add(st, "avail", NULL, 1, 1000*1000*1000, RRDDIM_ABSOLUTE);
 533                                                                         rrddim_add(st, "reserved_for_root", "reserved for root", 1, 1000*1000*1000, RRDDIM_ABSOLUTE);
 534                                                                         rrddim_add(st, "used" , NULL, 1, 1000*1000*1000, RRDDIM_ABSOLUTE);
 535                                                                 }
 536                                                                 else rrdset_next_usec(st, dt);
 537
 538                                                                 rrddim_set(st, "avail", space_avail);
 539                                                                 rrddim_set(st, "reserved_for_root", space_avail_root);
 540                                                                 rrddim_set(st, "used", space_used);
 541                                                                 rrdset_done(st);
 542                                                         }
 543                                                         if(ddo_inodes) {
 544                                                                 inodes_avail = buff_statvfs.f_favail;
 545                                                                 inodes_avail_root = buff_statvfs.f_ffree - buff_statvfs.f_favail;
 546                                                                 inodes_used = buff_statvfs.f_files - buff_statvfs.f_ffree;
 547
 548                                                                 st = rrdset_find_bytype("disk_inodes", disk);
 549                                                                 if(!st) {
 550                                                                         st = rrdset_create("disk_inodes", disk, NULL, family, "disk.inodes", "Disk Inodes Usage", "Inodes", 2024, update_every, RRDSET_TYPE_STACKED);
 551                                                                         st->isdetail = 1;
 552
 553                                                                         rrddim_add(st, "avail", NULL, 1, 1, RRDDIM_ABSOLUTE);
 554                                                                         rrddim_add(st, "reserved_for_root", "reserved for root", 1, 1, RRDDIM_ABSOLUTE);
 555                                                                         rrddim_add(st, "used" , NULL, 1, 1, RRDDIM_ABSOLUTE);
 556                                                                 }
 557                                                                 else rrdset_next_usec(st, dt);
 558
 559                                                                 rrddim_set(st, "avail", inodes_avail);
 560                                                                 rrddim_set(st, "reserved_for_root", inodes_avail_root);
 561                                                                 rrddim_set(st, "used", inodes_used);
 562                                                                 rrdset_done(st);
 563                                                         }
 564                                                 }
 565                                         }
 566                                 }
 567                         }
 568                 }
 569         }
 570         return 0;
 571 }