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