src/rrd.c

   1 #ifdef HAVE_CONFIG_H
   2 #include <config.h>
   3 #endif
   4 #include <stddef.h>
   5 #include <string.h>
   6 #include <unistd.h>
   7 #include <time.h>
   8 #include <sys/time.h>
   9 #include <sys/mman.h>
  10 #include <pthread.h>
  11 #include <errno.h>
  12 #include <ctype.h>
  13 #include <sys/stat.h>
  14 #include <sys/types.h>
  15 #include <stdlib.h>
  16
  17 #include "common.h"
  18 #include "log.h"
  19 #include "appconfig.h"
  20
  21 #include "rrd.h"
  22
  23 #define RRD_DEFAULT_GAP_INTERPOLATIONS 1
  24
  25 // ----------------------------------------------------------------------------
  26 // globals
  27
  28 // if not zero it gives the time (in seconds) to remove un-updated dimensions
  29 // DO NOT ENABLE
  30 // if dimensions are removed, the chart generation will have to run again
  31 int rrd_delete_unupdated_dimensions = 0;
  32
  33 int rrd_update_every = UPDATE_EVERY;
  34 int rrd_default_history_entries = RRD_DEFAULT_HISTORY_ENTRIES;
  35
  36 RRDSET *rrdset_root = NULL;
  37 pthread_rwlock_t rrdset_root_rwlock = PTHREAD_RWLOCK_INITIALIZER;
  38
  39 int rrd_memory_mode = RRD_MEMORY_MODE_SAVE;
  40
  41
  42 // ----------------------------------------------------------------------------
  43 // RRDSET index
  44
  45 static int rrdset_iterator(avl *a) { if(a) {}; return 0; }
  46
  47 static int rrdset_compare(void* a, void* b) {
  48         if(((RRDSET *)a)->hash < ((RRDSET *)b)->hash) return -1;
  49         else if(((RRDSET *)a)->hash > ((RRDSET *)b)->hash) return 1;
  50         else return strcmp(((RRDSET *)a)->id, ((RRDSET *)b)->id);
  51 }
  52
  53 avl_tree_lock rrdset_root_index = {
  54                 { NULL, rrdset_compare },
  55                 AVL_LOCK_INITIALIZER
  56 };
  57
  58 #define rrdset_index_add(st) avl_insert_lock(&rrdset_root_index, (avl *)(st))
  59 #define rrdset_index_del(st) avl_remove_lock(&rrdset_root_index, (avl *)(st))
  60
  61 static RRDSET *rrdset_index_find(const char *id, uint32_t hash) {
  62         RRDSET *result = NULL, tmp;
  63         strncpy(tmp.id, id, RRD_ID_LENGTH_MAX);
  64         tmp.id[RRD_ID_LENGTH_MAX] = '\0';
  65         tmp.hash = (hash)?hash:simple_hash(tmp.id);
  66
  67         avl_search_lock(&(rrdset_root_index), (avl *) &tmp, rrdset_iterator, (avl **) &result);
  68         return result;
  69 }
  70
  71 // ----------------------------------------------------------------------------
  72 // RRDSET name index
  73
  74 #define rrdset_from_avlname(avlname_ptr) ((RRDSET *)((avlname_ptr) - offsetof(RRDSET, avlname)))
  75
  76 static int rrdset_iterator_name(avl *a) { if(a) {}; return 0; }
  77
  78 static int rrdset_compare_name(void* a, void* b) {
  79         RRDSET *A = rrdset_from_avlname(a);
  80         RRDSET *B = rrdset_from_avlname(b);
  81
  82         // fprintf(stderr, "COMPARING: %s with %s\n", A->name, B->name);
  83
  84         if(A->hash_name < B->hash_name) return -1;
  85         else if(A->hash_name > B->hash_name) return 1;
  86         else return strcmp(A->name, B->name);
  87 }
  88
  89 avl_tree_lock rrdset_root_index_name = {
  90                 { NULL, rrdset_compare_name },
  91                 AVL_LOCK_INITIALIZER
  92 };
  93
  94 int rrdset_index_add_name(RRDSET *st) {
  95         // fprintf(stderr, "ADDING: %s (name: %s)\n", st->id, st->name);
  96         return avl_insert_lock(&rrdset_root_index_name, (avl *) (&st->avlname));
  97 }
  98
  99 #define rrdset_index_del_name(st) avl_remove_lock(&rrdset_root_index_name, (avl *)(&st->avlname))
 100
 101 static RRDSET *rrdset_index_find_name(const char *name, uint32_t hash) {
 102         void *result = NULL;
 103         RRDSET tmp;
 104         tmp.name = name;
 105         tmp.hash_name = (hash)?hash:simple_hash(tmp.name);
 106
 107         // fprintf(stderr, "SEARCHING: %s\n", name);
 108         avl_search_lock(&(rrdset_root_index_name), (avl *) (&(tmp.avlname)), rrdset_iterator_name, (avl **) &result);
 109         if(result) {
 110                 RRDSET *st = rrdset_from_avlname(result);
 111                 if(strcmp(st->magic, RRDSET_MAGIC))
 112                         error("Search for RRDSET %s returned an invalid RRDSET %s (name %s)", name, st->id, st->name);
 113
 114                 // fprintf(stderr, "FOUND: %s\n", name);
 115                 return rrdset_from_avlname(result);
 116         }
 117         // fprintf(stderr, "NOT FOUND: %s\n", name);
 118         return NULL;
 119 }
 120
 121
 122 // ----------------------------------------------------------------------------
 123 // RRDDIM index
 124
 125 static int rrddim_iterator(avl *a) { if(a) {}; return 0; }
 126
 127 static int rrddim_compare(void* a, void* b) {
 128         if(((RRDDIM *)a)->hash < ((RRDDIM *)b)->hash) return -1;
 129         else if(((RRDDIM *)a)->hash > ((RRDDIM *)b)->hash) return 1;
 130         else return strcmp(((RRDDIM *)a)->id, ((RRDDIM *)b)->id);
 131 }
 132
 133 #define rrddim_index_add(st, rd) avl_insert_lock(&((st)->dimensions_index), (avl *)(rd))
 134 #define rrddim_index_del(st,rd ) avl_remove_lock(&((st)->dimensions_index), (avl *)(rd))
 135
 136 static RRDDIM *rrddim_index_find(RRDSET *st, const char *id, uint32_t hash) {
 137         RRDDIM *result = NULL, tmp;
 138         strncpy(tmp.id, id, RRD_ID_LENGTH_MAX);
 139         tmp.id[RRD_ID_LENGTH_MAX] = '\0';
 140         tmp.hash = (hash)?hash:simple_hash(tmp.id);
 141
 142         avl_search_lock(&(st->dimensions_index), (avl *) &tmp, rrddim_iterator, (avl **) &result);
 143         return result;
 144 }
 145
 146 // ----------------------------------------------------------------------------
 147 // chart types
 148
 149 int rrdset_type_id(const char *name)
 150 {
 151         if(unlikely(strcmp(name, RRDSET_TYPE_AREA_NAME) == 0)) return RRDSET_TYPE_AREA;
 152         else if(unlikely(strcmp(name, RRDSET_TYPE_STACKED_NAME) == 0)) return RRDSET_TYPE_STACKED;
 153         else if(unlikely(strcmp(name, RRDSET_TYPE_LINE_NAME) == 0)) return RRDSET_TYPE_LINE;
 154         return RRDSET_TYPE_LINE;
 155 }
 156
 157 const char *rrdset_type_name(int chart_type)
 158 {
 159         static char line[] = RRDSET_TYPE_LINE_NAME;
 160         static char area[] = RRDSET_TYPE_AREA_NAME;
 161         static char stacked[] = RRDSET_TYPE_STACKED_NAME;
 162
 163         switch(chart_type) {
 164                 case RRDSET_TYPE_LINE:
 165                         return line;
 166
 167                 case RRDSET_TYPE_AREA:
 168                         return area;
 169
 170                 case RRDSET_TYPE_STACKED:
 171                         return stacked;
 172         }
 173         return line;
 174 }
 175
 176 // ----------------------------------------------------------------------------
 177 // load / save
 178
 179 const char *rrd_memory_mode_name(int id)
 180 {
 181         static const char ram[] = RRD_MEMORY_MODE_RAM_NAME;
 182         static const char map[] = RRD_MEMORY_MODE_MAP_NAME;
 183         static const char save[] = RRD_MEMORY_MODE_SAVE_NAME;
 184
 185         switch(id) {
 186                 case RRD_MEMORY_MODE_RAM:
 187                         return ram;
 188
 189                 case RRD_MEMORY_MODE_MAP:
 190                         return map;
 191
 192                 case RRD_MEMORY_MODE_SAVE:
 193                 default:
 194                         return save;
 195         }
 196
 197         return save;
 198 }
 199
 200 int rrd_memory_mode_id(const char *name)
 201 {
 202         if(unlikely(!strcmp(name, RRD_MEMORY_MODE_RAM_NAME)))
 203                 return RRD_MEMORY_MODE_RAM;
 204         else if(unlikely(!strcmp(name, RRD_MEMORY_MODE_MAP_NAME)))
 205                 return RRD_MEMORY_MODE_MAP;
 206
 207         return RRD_MEMORY_MODE_SAVE;
 208 }
 209
 210 // ----------------------------------------------------------------------------
 211 // algorithms types
 212
 213 int rrddim_algorithm_id(const char *name)
 214 {
 215         if(strcmp(name, RRDDIM_ABSOLUTE_NAME) == 0)                     return RRDDIM_ABSOLUTE;
 216         if(strcmp(name, RRDDIM_INCREMENTAL_NAME) == 0)                  return RRDDIM_INCREMENTAL;
 217         if(strcmp(name, RRDDIM_PCENT_OVER_ROW_TOTAL_NAME) == 0)                 return RRDDIM_PCENT_OVER_ROW_TOTAL;
 218         if(strcmp(name, RRDDIM_PCENT_OVER_DIFF_TOTAL_NAME) == 0)        return RRDDIM_PCENT_OVER_DIFF_TOTAL;
 219         return RRDDIM_ABSOLUTE;
 220 }
 221
 222 const char *rrddim_algorithm_name(int chart_type)
 223 {
 224         static char absolute[] = RRDDIM_ABSOLUTE_NAME;
 225         static char incremental[] = RRDDIM_INCREMENTAL_NAME;
 226         static char percentage_of_absolute_row[] = RRDDIM_PCENT_OVER_ROW_TOTAL_NAME;
 227         static char percentage_of_incremental_row[] = RRDDIM_PCENT_OVER_DIFF_TOTAL_NAME;
 228
 229         switch(chart_type) {
 230                 case RRDDIM_ABSOLUTE:
 231                         return absolute;
 232
 233                 case RRDDIM_INCREMENTAL:
 234                         return incremental;
 235
 236                 case RRDDIM_PCENT_OVER_ROW_TOTAL:
 237                         return percentage_of_absolute_row;
 238
 239                 case RRDDIM_PCENT_OVER_DIFF_TOTAL:
 240                         return percentage_of_incremental_row;
 241         }
 242         return absolute;
 243 }
 244
 245 // ----------------------------------------------------------------------------
 246 // chart names
 247
 248 char *rrdset_strncpy_name(char *to, const char *from, int length)
 249 {
 250         int i;
 251         for(i = 0; i < length && from[i] ;i++) {
 252                 if(from[i] == '.' || isalpha(from[i]) || isdigit(from[i])) to[i] = from[i];
 253                 else to[i] = '_';
 254         }
 255         if(i < length) to[i] = '\0';
 256         to[length - 1] = '\0';
 257
 258         return to;
 259 }
 260
 261 void rrdset_set_name(RRDSET *st, const char *name)
 262 {
 263         debug(D_RRD_CALLS, "rrdset_set_name() old: %s, new: %s", st->name, name);
 264
 265         if(st->name) rrdset_index_del_name(st);
 266
 267         char b[CONFIG_MAX_VALUE + 1];
 268         char n[RRD_ID_LENGTH_MAX + 1];
 269
 270         snprintf(n, RRD_ID_LENGTH_MAX, "%s.%s", st->type, name);
 271         rrdset_strncpy_name(b, n, CONFIG_MAX_VALUE);
 272         st->name = config_get(st->id, "name", b);
 273         st->hash_name = simple_hash(st->name);
 274
 275         rrdset_index_add_name(st);
 276 }
 277
 278 // ----------------------------------------------------------------------------
 279 // cache directory
 280
 281 char *rrdset_cache_dir(const char *id)
 282 {
 283         char *ret = NULL;
 284
 285         static char *cache_dir = NULL;
 286         if(!cache_dir) cache_dir = config_get("global", "cache directory", CACHE_DIR);
 287
 288         char b[FILENAME_MAX + 1];
 289         char n[FILENAME_MAX + 1];
 290         rrdset_strncpy_name(b, id, FILENAME_MAX);
 291
 292         snprintf(n, FILENAME_MAX, "%s/%s", cache_dir, b);
 293         ret = config_get(id, "cache directory", n);
 294
 295         if(rrd_memory_mode == RRD_MEMORY_MODE_MAP || rrd_memory_mode == RRD_MEMORY_MODE_SAVE) {
 296                 int r = mkdir(ret, 0775);
 297                 if(r != 0 && errno != EEXIST)
 298                         error("Cannot create directory '%s'", ret);
 299         }
 300
 301         return ret;
 302 }
 303
 304 // ----------------------------------------------------------------------------
 305 // core functions
 306
 307 void rrdset_reset(RRDSET *st)
 308 {
 309         debug(D_RRD_CALLS, "rrdset_reset() %s", st->name);
 310
 311         st->last_collected_time.tv_sec = 0;
 312         st->last_collected_time.tv_usec = 0;
 313         st->last_updated.tv_sec = 0;
 314         st->last_updated.tv_usec = 0;
 315         st->current_entry = 0;
 316         st->counter = 0;
 317         st->counter_done = 0;
 318
 319         RRDDIM *rd;
 320         for(rd = st->dimensions; rd ; rd = rd->next) {
 321                 rd->last_collected_time.tv_sec = 0;
 322                 rd->last_collected_time.tv_usec = 0;
 323                 rd->counter = 0;
 324                 bzero(rd->values, rd->entries * sizeof(storage_number));
 325         }
 326 }
 327
 328 RRDSET *rrdset_create(const char *type, const char *id, const char *name, const char *family, const char *context, const char *title, const char *units, long priority, int update_every, int chart_type)
 329 {
 330         if(!type || !type[0]) {
 331                 fatal("Cannot create rrd stats without a type.");
 332                 return NULL;
 333         }
 334
 335         if(!id || !id[0]) {
 336                 fatal("Cannot create rrd stats without an id.");
 337                 return NULL;
 338         }
 339
 340         char fullid[RRD_ID_LENGTH_MAX + 1];
 341         char fullfilename[FILENAME_MAX + 1];
 342         RRDSET *st = NULL;
 343
 344         snprintf(fullid, RRD_ID_LENGTH_MAX, "%s.%s", type, id);
 345
 346         st = rrdset_find(fullid);
 347         if(st) {
 348                 error("Cannot create rrd stats for '%s', it already exists.", fullid);
 349                 return st;
 350         }
 351
 352         long entries = config_get_number(fullid, "history", rrd_default_history_entries);
 353         if(entries < 5) entries = config_set_number(fullid, "history", 5);
 354         if(entries > RRD_HISTORY_ENTRIES_MAX) entries = config_set_number(fullid, "history", RRD_HISTORY_ENTRIES_MAX);
 355
 356         int enabled = config_get_boolean(fullid, "enabled", 1);
 357         if(!enabled) entries = 5;
 358
 359         unsigned long size = sizeof(RRDSET);
 360         char *cache_dir = rrdset_cache_dir(fullid);
 361
 362         debug(D_RRD_CALLS, "Creating RRD_STATS for '%s.%s'.", type, id);
 363
 364         snprintf(fullfilename, FILENAME_MAX, "%s/main.db", cache_dir);
 365         if(rrd_memory_mode != RRD_MEMORY_MODE_RAM) st = (RRDSET *)mymmap(fullfilename, size, ((rrd_memory_mode == RRD_MEMORY_MODE_MAP)?MAP_SHARED:MAP_PRIVATE), 0);
 366         if(st) {
 367                 if(strcmp(st->magic, RRDSET_MAGIC) != 0) {
 368                         errno = 0;
 369                         info("Initializing file %s.", fullfilename);
 370                         bzero(st, size);
 371                 }
 372                 else if(strcmp(st->id, fullid) != 0) {
 373                         errno = 0;
 374                         error("File %s contents are not for chart %s. Clearing it.", fullfilename, fullid);
 375                         // munmap(st, size);
 376                         // st = NULL;
 377                         bzero(st, size);
 378                 }
 379                 else if(st->memsize != size || st->entries != entries) {
 380                         errno = 0;
 381                         error("File %s does not have the desired size. Clearing it.", fullfilename);
 382                         bzero(st, size);
 383                 }
 384                 else if(st->update_every != update_every) {
 385                         errno = 0;
 386                         error("File %s does not have the desired update frequency. Clearing it.", fullfilename);
 387                         bzero(st, size);
 388                 }
 389                 else if((time(NULL) - st->last_updated.tv_sec) > update_every * entries) {
 390                         errno = 0;
 391                         error("File %s is too old. Clearing it.", fullfilename);
 392                         bzero(st, size);
 393                 }
 394         }
 395
 396         if(st) {
 397                 st->name = NULL;
 398                 st->type = NULL;
 399                 st->family = NULL;
 400                 st->context = NULL;
 401                 st->title = NULL;
 402                 st->units = NULL;
 403                 st->dimensions = NULL;
 404                 st->next = NULL;
 405                 st->mapped = rrd_memory_mode;
 406         }
 407         else {
 408                 st = calloc(1, size);
 409                 if(!st) {
 410                         fatal("Cannot allocate memory for RRD_STATS %s.%s", type, id);
 411                         return NULL;
 412                 }
 413                 st->mapped = RRD_MEMORY_MODE_RAM;
 414         }
 415         st->memsize = size;
 416         st->entries = entries;
 417         st->update_every = update_every;
 418
 419         strcpy(st->cache_filename, fullfilename);
 420         strcpy(st->magic, RRDSET_MAGIC);
 421
 422         strcpy(st->id, fullid);
 423         st->hash = simple_hash(st->id);
 424
 425         st->cache_dir = cache_dir;
 426
 427         st->chart_type = rrdset_type_id(config_get(st->id, "chart type", rrdset_type_name(chart_type)));
 428         st->type       = config_get(st->id, "type", type);
 429         st->family     = config_get(st->id, "family", family?family:st->type);
 430         st->context    = config_get(st->id, "context", context?context:st->id);
 431         st->units      = config_get(st->id, "units", units?units:"");
 432
 433         st->priority = config_get_number(st->id, "priority", priority);
 434         st->enabled = enabled;
 435
 436         st->isdetail = 0;
 437         st->debug = 0;
 438
 439         st->last_collected_time.tv_sec = 0;
 440         st->last_collected_time.tv_usec = 0;
 441         st->counter_done = 0;
 442
 443         st->gap_when_lost_iterations_above = (int) (
 444                         config_get_number(st->id, "gap when lost iterations above", RRD_DEFAULT_GAP_INTERPOLATIONS) + 2);
 445
 446         avl_init_lock(&st->dimensions_index, rrddim_compare);
 447
 448         pthread_rwlock_init(&st->rwlock, NULL);
 449         pthread_rwlock_wrlock(&rrdset_root_rwlock);
 450
 451         if(name && *name) rrdset_set_name(st, name);
 452         else rrdset_set_name(st, id);
 453
 454         {
 455                 char varvalue[CONFIG_MAX_VALUE + 1];
 456                 snprintf(varvalue, CONFIG_MAX_VALUE, "%s (%s)", title?title:"", st->name);
 457                 st->title = config_get(st->id, "title", varvalue);
 458         }
 459
 460         st->next = rrdset_root;
 461         rrdset_root = st;
 462
 463         rrdset_index_add(st);
 464
 465         pthread_rwlock_unlock(&rrdset_root_rwlock);
 466
 467         return(st);
 468 }
 469
 470 RRDDIM *rrddim_add(RRDSET *st, const char *id, const char *name, long multiplier, long divisor, int algorithm)
 471 {
 472         char filename[FILENAME_MAX + 1];
 473         char fullfilename[FILENAME_MAX + 1];
 474
 475         char varname[CONFIG_MAX_NAME + 1];
 476         RRDDIM *rd = NULL;
 477         unsigned long size = sizeof(RRDDIM) + (st->entries * sizeof(storage_number));
 478
 479         debug(D_RRD_CALLS, "Adding dimension '%s/%s'.", st->id, id);
 480
 481         rrdset_strncpy_name(filename, id, FILENAME_MAX);
 482         snprintf(fullfilename, FILENAME_MAX, "%s/%s.db", st->cache_dir, filename);
 483         if(rrd_memory_mode != RRD_MEMORY_MODE_RAM) rd = (RRDDIM *)mymmap(fullfilename, size, ((rrd_memory_mode == RRD_MEMORY_MODE_MAP)?MAP_SHARED:MAP_PRIVATE), 1);
 484         if(rd) {
 485                 struct timeval now;
 486                 gettimeofday(&now, NULL);
 487
 488                 if(strcmp(rd->magic, RRDDIMENSION_MAGIC) != 0) {
 489                         errno = 0;
 490                         info("Initializing file %s.", fullfilename);
 491                         bzero(rd, size);
 492                 }
 493                 else if(rd->memsize != size) {
 494                         errno = 0;
 495                         error("File %s does not have the desired size. Clearing it.", fullfilename);
 496                         bzero(rd, size);
 497                 }
 498                 else if(rd->multiplier != multiplier) {
 499                         errno = 0;
 500                         error("File %s does not have the same multiplier. Clearing it.", fullfilename);
 501                         bzero(rd, size);
 502                 }
 503                 else if(rd->divisor != divisor) {
 504                         errno = 0;
 505                         error("File %s does not have the same divisor. Clearing it.", fullfilename);
 506                         bzero(rd, size);
 507                 }
 508                 else if(rd->algorithm != algorithm) {
 509                         errno = 0;
 510                         error("File %s does not have the same algorithm. Clearing it.", fullfilename);
 511                         bzero(rd, size);
 512                 }
 513                 else if(rd->update_every != st->update_every) {
 514                         errno = 0;
 515                         error("File %s does not have the same refresh frequency. Clearing it.", fullfilename);
 516                         bzero(rd, size);
 517                 }
 518                 else if(usecdiff(&now, &rd->last_collected_time) > (rd->entries * rd->update_every * 1000000ULL)) {
 519                         errno = 0;
 520                         error("File %s is too old. Clearing it.", fullfilename);
 521                         bzero(rd, size);
 522                 }
 523                 else if(strcmp(rd->id, id) != 0) {
 524                         errno = 0;
 525                         error("File %s contents are not for dimension %s. Clearing it.", fullfilename, id);
 526                         // munmap(rd, size);
 527                         // rd = NULL;
 528                         bzero(rd, size);
 529                 }
 530         }
 531
 532         if(rd) {
 533                 // we have a file mapped for rd
 534                 rd->mapped = rrd_memory_mode;
 535                 rd->flags = 0x00000000;
 536                 rd->next = NULL;
 537                 rd->name = NULL;
 538         }
 539         else {
 540                 // if we didn't manage to get a mmap'd dimension, just create one
 541
 542                 rd = calloc(1, size);
 543                 if(!rd) {
 544                         fatal("Cannot allocate RRD_DIMENSION %s/%s.", st->id, id);
 545                         return NULL;
 546                 }
 547
 548                 rd->mapped = RRD_MEMORY_MODE_RAM;
 549         }
 550         rd->memsize = size;
 551
 552         strcpy(rd->magic, RRDDIMENSION_MAGIC);
 553         strcpy(rd->cache_filename, fullfilename);
 554         strncpy(rd->id, id, RRD_ID_LENGTH_MAX);
 555         rd->hash = simple_hash(rd->id);
 556
 557         snprintf(varname, CONFIG_MAX_NAME, "dim %s name", rd->id);
 558         rd->name = config_get(st->id, varname, (name && *name)?name:rd->id);
 559
 560         snprintf(varname, CONFIG_MAX_NAME, "dim %s algorithm", rd->id);
 561         rd->algorithm = rrddim_algorithm_id(config_get(st->id, varname, rrddim_algorithm_name(algorithm)));
 562
 563         snprintf(varname, CONFIG_MAX_NAME, "dim %s multiplier", rd->id);
 564         rd->multiplier = config_get_number(st->id, varname, multiplier);
 565
 566         snprintf(varname, CONFIG_MAX_NAME, "dim %s divisor", rd->id);
 567         rd->divisor = config_get_number(st->id, varname, divisor);
 568         if(!rd->divisor) rd->divisor = 1;
 569
 570         rd->entries = st->entries;
 571         rd->update_every = st->update_every;
 572
 573         // prevent incremental calculation spikes
 574         rd->counter = 0;
 575
 576         // append this dimension
 577         pthread_rwlock_wrlock(&st->rwlock);
 578         if(!st->dimensions)
 579                 st->dimensions = rd;
 580         else {
 581                 RRDDIM *td = st->dimensions;
 582                 for(; td->next; td = td->next) ;
 583                 td->next = rd;
 584         }
 585         pthread_rwlock_unlock(&st->rwlock);
 586
 587         rrddim_index_add(st, rd);
 588
 589         return(rd);
 590 }
 591
 592 void rrddim_set_name(RRDSET *st, RRDDIM *rd, const char *name)
 593 {
 594         debug(D_RRD_CALLS, "rrddim_set_name() %s.%s", st->name, rd->name);
 595
 596         char varname[CONFIG_MAX_NAME + 1];
 597         snprintf(varname, CONFIG_MAX_NAME, "dim %s name", rd->id);
 598         config_set_default(st->id, varname, name);
 599 }
 600
 601 void rrddim_free(RRDSET *st, RRDDIM *rd)
 602 {
 603         debug(D_RRD_CALLS, "rrddim_free() %s.%s", st->name, rd->name);
 604
 605         RRDDIM *i, *last = NULL;
 606         for(i = st->dimensions; i && i != rd ; i = i->next) last = i;
 607
 608         if(!i) {
 609                 error("Request to free dimension %s.%s but it is not linked.", st->id, rd->name);
 610                 return;
 611         }
 612
 613         if(last) last->next = rd->next;
 614         else st->dimensions = rd->next;
 615         rd->next = NULL;
 616
 617         rrddim_index_del(st, rd);
 618
 619         // free(rd->annotations);
 620         if(rd->mapped == RRD_MEMORY_MODE_SAVE) {
 621                 debug(D_RRD_CALLS, "Saving dimension '%s' to '%s'.", rd->name, rd->cache_filename);
 622                 savememory(rd->cache_filename, rd, rd->memsize);
 623
 624                 debug(D_RRD_CALLS, "Unmapping dimension '%s'.", rd->name);
 625                 munmap(rd, rd->memsize);
 626         }
 627         else if(rd->mapped == RRD_MEMORY_MODE_MAP) {
 628                 debug(D_RRD_CALLS, "Unmapping dimension '%s'.", rd->name);
 629                 munmap(rd, rd->memsize);
 630         }
 631         else {
 632                 debug(D_RRD_CALLS, "Removing dimension '%s'.", rd->name);
 633                 free(rd);
 634         }
 635 }
 636
 637 void rrdset_free_all(void)
 638 {
 639         info("Freeing all memory...");
 640
 641         RRDSET *st;
 642         for(st = rrdset_root; st ;) {
 643                 RRDSET *next = st->next;
 644
 645                 while(st->dimensions)
 646                         rrddim_free(st, st->dimensions);
 647
 648                 rrdset_index_del(st);
 649
 650                 if(st->mapped == RRD_MEMORY_MODE_SAVE) {
 651                         debug(D_RRD_CALLS, "Saving stats '%s' to '%s'.", st->name, st->cache_filename);
 652                         savememory(st->cache_filename, st, st->memsize);
 653
 654                         debug(D_RRD_CALLS, "Unmapping stats '%s'.", st->name);
 655                         munmap(st, st->memsize);
 656                 }
 657                 else if(st->mapped == RRD_MEMORY_MODE_MAP) {
 658                         debug(D_RRD_CALLS, "Unmapping stats '%s'.", st->name);
 659                         munmap(st, st->memsize);
 660                 }
 661                 else
 662                         free(st);
 663
 664                 st = next;
 665         }
 666         rrdset_root = NULL;
 667
 668         info("Memory cleanup completed...");
 669 }
 670
 671 void rrdset_save_all(void)
 672 {
 673         debug(D_RRD_CALLS, "rrdset_save_all()");
 674
 675         // let it log a few error messages
 676         error_log_limit_reset();
 677
 678         RRDSET *st;
 679         RRDDIM *rd;
 680
 681         pthread_rwlock_wrlock(&rrdset_root_rwlock);
 682         for(st = rrdset_root; st ; st = st->next) {
 683                 pthread_rwlock_wrlock(&st->rwlock);
 684
 685                 if(st->mapped == RRD_MEMORY_MODE_SAVE) {
 686                         debug(D_RRD_CALLS, "Saving stats '%s' to '%s'.", st->name, st->cache_filename);
 687                         savememory(st->cache_filename, st, st->memsize);
 688                 }
 689
 690                 for(rd = st->dimensions; rd ; rd = rd->next) {
 691                         if(likely(rd->mapped == RRD_MEMORY_MODE_SAVE)) {
 692                                 debug(D_RRD_CALLS, "Saving dimension '%s' to '%s'.", rd->name, rd->cache_filename);
 693                                 savememory(rd->cache_filename, rd, rd->memsize);
 694                         }
 695                 }
 696
 697                 pthread_rwlock_unlock(&st->rwlock);
 698         }
 699         pthread_rwlock_unlock(&rrdset_root_rwlock);
 700 }
 701
 702
 703 RRDSET *rrdset_find(const char *id)
 704 {
 705         debug(D_RRD_CALLS, "rrdset_find() for chart %s", id);
 706
 707         RRDSET *st = rrdset_index_find(id, 0);
 708         return(st);
 709 }
 710
 711 RRDSET *rrdset_find_bytype(const char *type, const char *id)
 712 {
 713         debug(D_RRD_CALLS, "rrdset_find_bytype() for chart %s.%s", type, id);
 714
 715         char buf[RRD_ID_LENGTH_MAX + 1];
 716
 717         strncpy(buf, type, RRD_ID_LENGTH_MAX - 1);
 718         buf[RRD_ID_LENGTH_MAX - 1] = '\0';
 719         strcat(buf, ".");
 720         int len = (int) strlen(buf);
 721         strncpy(&buf[len], id, (size_t) (RRD_ID_LENGTH_MAX - len));
 722         buf[RRD_ID_LENGTH_MAX] = '\0';
 723
 724         return(rrdset_find(buf));
 725 }
 726
 727 RRDSET *rrdset_find_byname(const char *name)
 728 {
 729         debug(D_RRD_CALLS, "rrdset_find_byname() for chart %s", name);
 730
 731         RRDSET *st = rrdset_index_find_name(name, 0);
 732         return(st);
 733 }
 734
 735 RRDDIM *rrddim_find(RRDSET *st, const char *id)
 736 {
 737         debug(D_RRD_CALLS, "rrddim_find() for chart %s, dimension %s", st->name, id);
 738
 739         return rrddim_index_find(st, id, 0);
 740 }
 741
 742 int rrddim_hide(RRDSET *st, const char *id)
 743 {
 744         debug(D_RRD_CALLS, "rrddim_hide() for chart %s, dimension %s", st->name, id);
 745
 746         RRDDIM *rd = rrddim_find(st, id);
 747         if(unlikely(!rd)) {
 748                 error("Cannot find dimension with id '%s' on stats '%s' (%s).", id, st->name, st->id);
 749                 return 1;
 750         }
 751
 752         rd->flags |= RRDDIM_FLAG_HIDDEN;
 753         return 0;
 754 }
 755
 756 int rrddim_unhide(RRDSET *st, const char *id)
 757 {
 758         debug(D_RRD_CALLS, "rrddim_unhide() for chart %s, dimension %s", st->name, id);
 759
 760         RRDDIM *rd = rrddim_find(st, id);
 761         if(unlikely(!rd)) {
 762                 error("Cannot find dimension with id '%s' on stats '%s' (%s).", id, st->name, st->id);
 763                 return 1;
 764         }
 765
 766         if(rd->flags & RRDDIM_FLAG_HIDDEN) rd->flags ^= RRDDIM_FLAG_HIDDEN;
 767         return 0;
 768 }
 769
 770 collected_number rrddim_set_by_pointer(RRDSET *st, RRDDIM *rd, collected_number value)
 771 {
 772         debug(D_RRD_CALLS, "rrddim_set_by_pointer() for chart %s, dimension %s, value " COLLECTED_NUMBER_FORMAT, st->name, rd->name, value);
 773
 774         gettimeofday(&rd->last_collected_time, NULL);
 775         rd->collected_value = value;
 776         rd->updated = 1;
 777         rd->counter++;
 778
 779         return rd->last_collected_value;
 780 }
 781
 782 collected_number rrddim_set(RRDSET *st, const char *id, collected_number value)
 783 {
 784         RRDDIM *rd = rrddim_find(st, id);
 785         if(unlikely(!rd)) {
 786                 error("Cannot find dimension with id '%s' on stats '%s' (%s).", id, st->name, st->id);
 787                 return 0;
 788         }
 789
 790         return rrddim_set_by_pointer(st, rd, value);
 791 }
 792
 793 void rrdset_next_usec(RRDSET *st, unsigned long long microseconds)
 794 {
 795         if(!microseconds) rrdset_next(st);
 796         else {
 797                 debug(D_RRD_CALLS, "rrdset_next_usec() for chart %s with microseconds %llu", st->name, microseconds);
 798
 799                 if(unlikely(st->debug)) debug(D_RRD_STATS, "%s: NEXT: %llu microseconds", st->name, microseconds);
 800                 st->usec_since_last_update = microseconds;
 801         }
 802 }
 803
 804 void rrdset_next(RRDSET *st)
 805 {
 806         unsigned long long microseconds = 0;
 807
 808         if(likely(st->last_collected_time.tv_sec)) {
 809                 struct timeval now;
 810                 gettimeofday(&now, NULL);
 811                 microseconds = usecdiff(&now, &st->last_collected_time);
 812         }
 813         // prevent infinite loop
 814         else microseconds = st->update_every * 1000000ULL;
 815
 816         rrdset_next_usec(st, microseconds);
 817 }
 818
 819 void rrdset_next_plugins(RRDSET *st)
 820 {
 821         rrdset_next(st);
 822 }
 823
 824 unsigned long long rrdset_done(RRDSET *st)
 825 {
 826         debug(D_RRD_CALLS, "rrdset_done() for chart %s", st->name);
 827
 828         RRDDIM *rd, *last;
 829         int oldstate, store_this_entry = 1, first_entry = 0;
 830         unsigned long long last_ut, now_ut, next_ut, stored_entries = 0;
 831
 832         if(unlikely(pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &oldstate) != 0))
 833                 error("Cannot set pthread cancel state to DISABLE.");
 834
 835         // a read lock is OK here
 836         pthread_rwlock_rdlock(&st->rwlock);
 837
 838         // enable the chart, if it was disabled
 839         if(unlikely(rrd_delete_unupdated_dimensions) && !st->enabled)
 840                 st->enabled = 1;
 841
 842         // check if the chart has a long time to be updated
 843         if(unlikely(st->usec_since_last_update > st->entries * st->update_every * 1000000ULL)) {
 844                 info("%s: took too long to be updated (%0.3Lf secs). Reseting it.", st->name, (long double)(st->usec_since_last_update / 1000000.0));
 845                 rrdset_reset(st);
 846                 st->usec_since_last_update = st->update_every * 1000000ULL;
 847                 first_entry = 1;
 848         }
 849         if(unlikely(st->debug)) debug(D_RRD_STATS, "%s: microseconds since last update: %llu", st->name, st->usec_since_last_update);
 850
 851         // set last_collected_time
 852         if(unlikely(!st->last_collected_time.tv_sec)) {
 853                 // it is the first entry
 854                 // set the last_collected_time to now
 855                 gettimeofday(&st->last_collected_time, NULL);
 856
 857                 // the first entry should not be stored
 858                 store_this_entry = 0;
 859                 first_entry = 1;
 860
 861                 if(unlikely(st->debug)) debug(D_RRD_STATS, "%s: has not set last_collected_time. Setting it now. Will not store the next entry.", st->name);
 862         }
 863         else {
 864                 // it is not the first entry
 865                 // calculate the proper last_collected_time, using usec_since_last_update
 866                 unsigned long long ut = st->last_collected_time.tv_sec * 1000000ULL + st->last_collected_time.tv_usec + st->usec_since_last_update;
 867                 st->last_collected_time.tv_sec = (time_t) (ut / 1000000ULL);
 868                 st->last_collected_time.tv_usec = (useconds_t) (ut % 1000000ULL);
 869         }
 870
 871         // if this set has not been updated in the past
 872         // we fake the last_update time to be = now - usec_since_last_update
 873         if(unlikely(!st->last_updated.tv_sec)) {
 874                 // it has never been updated before
 875                 // set a fake last_updated, in the past using usec_since_last_update
 876                 unsigned long long ut = st->last_collected_time.tv_sec * 1000000ULL + st->last_collected_time.tv_usec - st->usec_since_last_update;
 877                 st->last_updated.tv_sec = (time_t) (ut / 1000000ULL);
 878                 st->last_updated.tv_usec = (useconds_t) (ut % 1000000ULL);
 879
 880                 // the first entry should not be stored
 881                 store_this_entry = 0;
 882                 first_entry = 1;
 883
 884                 if(unlikely(st->debug)) debug(D_RRD_STATS, "%s: initializing last_updated to now - %llu microseconds (%0.3Lf). Will not store the next entry.", st->name, st->usec_since_last_update, (long double)ut/1000000.0);
 885         }
 886
 887         // check if we will re-write the entire data set
 888         if(unlikely(usecdiff(&st->last_collected_time, &st->last_updated) > st->update_every * st->entries * 1000000ULL)) {
 889                 info("%s: too old data (last updated at %u.%u, last collected at %u.%u). Reseting it. Will not store the next entry.", st->name, st->last_updated.tv_sec, st->last_updated.tv_usec, st->last_collected_time.tv_sec, st->last_collected_time.tv_usec);
 890                 rrdset_reset(st);
 891
 892                 st->usec_since_last_update = st->update_every * 1000000ULL;
 893
 894                 gettimeofday(&st->last_collected_time, NULL);
 895
 896                 unsigned long long ut = st->last_collected_time.tv_sec * 1000000ULL + st->last_collected_time.tv_usec - st->usec_since_last_update;
 897                 st->last_updated.tv_sec = (time_t) (ut / 1000000ULL);
 898                 st->last_updated.tv_usec = (useconds_t) (ut % 1000000ULL);
 899
 900                 // the first entry should not be stored
 901                 store_this_entry = 0;
 902                 first_entry = 1;
 903         }
 904
 905         // these are the 3 variables that will help us in interpolation
 906         // last_ut = the last time we added a value to the storage
 907         //  now_ut = the time the current value is taken at
 908         // next_ut = the time of the next interpolation point
 909         last_ut = st->last_updated.tv_sec * 1000000ULL + st->last_updated.tv_usec;
 910         now_ut  = st->last_collected_time.tv_sec * 1000000ULL + st->last_collected_time.tv_usec;
 911         next_ut = (st->last_updated.tv_sec + st->update_every) * 1000000ULL;
 912
 913         if(unlikely(!first_entry && now_ut < next_ut)) {
 914                 if(unlikely(st->debug)) debug(D_RRD_STATS, "%s: THIS IS IN THE SAME INTERPOLATION POINT", st->name);
 915         }
 916
 917         if(unlikely(st->debug)) {
 918                 debug(D_RRD_STATS, "%s: last ut = %0.3Lf (last updated time)", st->name, (long double)last_ut/1000000.0);
 919                 debug(D_RRD_STATS, "%s: now  ut = %0.3Lf (current update time)", st->name, (long double)now_ut/1000000.0);
 920                 debug(D_RRD_STATS, "%s: next ut = %0.3Lf (next interpolation point)", st->name, (long double)next_ut/1000000.0);
 921         }
 922
 923         if(unlikely(!st->counter_done)) {
 924                 store_this_entry = 0;
 925                 if(unlikely(st->debug)) debug(D_RRD_STATS, "%s: Will not store the next entry.", st->name);
 926         }
 927         st->counter_done++;
 928
 929         // calculate totals and count the dimensions
 930         int dimensions;
 931         st->collected_total = 0;
 932         for( rd = st->dimensions, dimensions = 0 ; likely(rd) ; rd = rd->next, dimensions++ )
 933                 st->collected_total += rd->collected_value;
 934
 935         uint32_t storage_flags = SN_EXISTS;
 936
 937         // process all dimensions to calculate their values
 938         // based on the collected figures only
 939         // at this stage we do not interpolate anything
 940         for( rd = st->dimensions ; likely(rd) ; rd = rd->next ) {
 941
 942                 if(unlikely(st->debug)) debug(D_RRD_STATS, "%s/%s: START "
 943                         " last_collected_value = " COLLECTED_NUMBER_FORMAT
 944                         " collected_value = " COLLECTED_NUMBER_FORMAT
 945                         " last_calculated_value = " CALCULATED_NUMBER_FORMAT
 946                         " calculated_value = " CALCULATED_NUMBER_FORMAT
 947                         , st->id, rd->name
 948                         , rd->last_collected_value
 949                         , rd->collected_value
 950                         , rd->last_calculated_value
 951                         , rd->calculated_value
 952                         );
 953
 954                 switch(rd->algorithm) {
 955                 case RRDDIM_ABSOLUTE:
 956                         rd->calculated_value = (calculated_number)rd->collected_value
 957                                 * (calculated_number)rd->multiplier
 958                                 / (calculated_number)rd->divisor;
 959
 960                         if(unlikely(st->debug))
 961                                 debug(D_RRD_STATS, "%s/%s: CALC ABS/ABS-NO-IN "
 962                                         CALCULATED_NUMBER_FORMAT " = "
 963                                         COLLECTED_NUMBER_FORMAT
 964                                         " * " CALCULATED_NUMBER_FORMAT
 965                                         " / " CALCULATED_NUMBER_FORMAT
 966                                         , st->id, rd->name
 967                                         , rd->calculated_value
 968                                         , rd->collected_value
 969                                         , (calculated_number)rd->multiplier
 970                                         , (calculated_number)rd->divisor
 971                                         );
 972                         break;
 973
 974                         case RRDDIM_PCENT_OVER_ROW_TOTAL:
 975                                 if(unlikely(!st->collected_total)) rd->calculated_value = 0;
 976                                 else
 977                                 // the percentage of the current value
 978                                 // over the total of all dimensions
 979                                 rd->calculated_value =
 980                                           (calculated_number)100
 981                                         * (calculated_number)rd->collected_value
 982                                         / (calculated_number)st->collected_total;
 983
 984                                 if(unlikely(st->debug))
 985                                         debug(D_RRD_STATS, "%s/%s: CALC PCENT-ROW "
 986                                                 CALCULATED_NUMBER_FORMAT " = 100"
 987                                                 " * " COLLECTED_NUMBER_FORMAT
 988                                                 " / " COLLECTED_NUMBER_FORMAT
 989                                                 , st->id, rd->name
 990                                                 , rd->calculated_value
 991                                                 , rd->collected_value
 992                                                 , st->collected_total
 993                                                 );
 994                                 break;
 995
 996                         case RRDDIM_INCREMENTAL:
 997                                 if(unlikely(!rd->updated || rd->counter <= 1)) {
 998                                         rd->calculated_value = 0;
 999                                         continue;
1000                                 }
1001
1002                                 // if the new is smaller than the old (an overflow, or reset), set the old equal to the new
1003                                 // to reset the calculation (it will give zero as the calculation for this second)
1004                                 if(unlikely(rd->last_collected_value > rd->collected_value)) {
1005                                         debug(D_RRD_STATS, "%s.%s: RESET or OVERFLOW. Last collected value = " COLLECTED_NUMBER_FORMAT ", current = " COLLECTED_NUMBER_FORMAT
1006                                                         , st->name, rd->name
1007                                                         , rd->last_collected_value
1008                                                         , rd->collected_value);
1009                                         if(!(rd->flags & RRDDIM_FLAG_DONT_DETECT_RESETS_OR_OVERFLOWS)) storage_flags = SN_EXISTS_RESET;
1010                                         rd->last_collected_value = rd->collected_value;
1011                                 }
1012
1013                                 rd->calculated_value = (calculated_number)(rd->collected_value - rd->last_collected_value)
1014                                         * (calculated_number)rd->multiplier
1015                                         / (calculated_number)rd->divisor;
1016
1017                                 if(unlikely(st->debug))
1018                                         debug(D_RRD_STATS, "%s/%s: CALC INC PRE "
1019                                                 CALCULATED_NUMBER_FORMAT " = ("
1020                                                 COLLECTED_NUMBER_FORMAT " - " COLLECTED_NUMBER_FORMAT
1021                                                 ")"
1022                                                 " * " CALCULATED_NUMBER_FORMAT
1023                                                 " / " CALCULATED_NUMBER_FORMAT
1024                                                 , st->id, rd->name
1025                                                 , rd->calculated_value
1026                                                 , rd->collected_value, rd->last_collected_value
1027                                                 , (calculated_number)rd->multiplier
1028                                                 , (calculated_number)rd->divisor
1029                                                 );
1030                                 break;
1031
1032                         case RRDDIM_PCENT_OVER_DIFF_TOTAL:
1033                                 if(unlikely(!rd->updated || rd->counter <= 1)) {
1034                                         rd->calculated_value = 0;
1035                                         continue;
1036                                 }
1037
1038                                 // the percentage of the current increment
1039                                 // over the increment of all dimensions together
1040                                 if(unlikely(st->collected_total == st->last_collected_total)) rd->calculated_value = rd->last_calculated_value;
1041                                 else rd->calculated_value =
1042                                           (calculated_number)100
1043                                         * (calculated_number)(rd->collected_value - rd->last_collected_value)
1044                                         / (calculated_number)(st->collected_total  - st->last_collected_total);
1045
1046                                 if(unlikely(st->debug))
1047                                         debug(D_RRD_STATS, "%s/%s: CALC PCENT-DIFF "
1048                                                 CALCULATED_NUMBER_FORMAT " = 100"
1049                                                 " * (" COLLECTED_NUMBER_FORMAT " - " COLLECTED_NUMBER_FORMAT ")"
1050                                                 " / (" COLLECTED_NUMBER_FORMAT " - " COLLECTED_NUMBER_FORMAT ")"
1051                                                 , st->id, rd->name
1052                                                 , rd->calculated_value
1053                                                 , rd->collected_value, rd->last_collected_value
1054                                                 , st->collected_total, st->last_collected_total
1055                                                 );
1056                                 break;
1057
1058                         default:
1059                                 // make the default zero, to make sure
1060                                 // it gets noticed when we add new types
1061                                 rd->calculated_value = 0;
1062
1063                                 if(unlikely(st->debug))
1064                                         debug(D_RRD_STATS, "%s/%s: CALC "
1065                                                 CALCULATED_NUMBER_FORMAT " = 0"
1066                                                 , st->id, rd->name
1067                                                 , rd->calculated_value
1068                                                 );
1069                                 break;
1070                 }
1071
1072                 if(unlikely(st->debug)) debug(D_RRD_STATS, "%s/%s: PHASE2 "
1073                         " last_collected_value = " COLLECTED_NUMBER_FORMAT
1074                         " collected_value = " COLLECTED_NUMBER_FORMAT
1075                         " last_calculated_value = " CALCULATED_NUMBER_FORMAT
1076                         " calculated_value = " CALCULATED_NUMBER_FORMAT
1077                         , st->id, rd->name
1078                         , rd->last_collected_value
1079                         , rd->collected_value
1080                         , rd->last_calculated_value
1081                         , rd->calculated_value
1082                         );
1083
1084         }
1085
1086         // at this point we have all the calculated values ready
1087         // it is now time to interpolate values on a second boundary
1088
1089         unsigned long long first_ut = last_ut;
1090         long long iterations = (now_ut - last_ut) / (st->update_every * 1000000ULL);
1091         if((now_ut % (st->update_every * 1000000ULL)) == 0) iterations++;
1092
1093         for( ; likely(next_ut <= now_ut) ; next_ut += st->update_every * 1000000ULL, iterations-- ) {
1094 #ifdef NETDATA_INTERNAL_CHECKS
1095                 if(iterations < 0) { error("%s: iterations calculation wrapped! first_ut = %llu, last_ut = %llu, next_ut = %llu, now_ut = %llu", st->name, first_ut, last_ut, next_ut, now_ut); }
1096 #endif
1097
1098                 if(unlikely(st->debug)) {
1099                         debug(D_RRD_STATS, "%s: last ut = %0.3Lf (last updated time)", st->name, (long double)last_ut/1000000.0);
1100                         debug(D_RRD_STATS, "%s: next ut = %0.3Lf (next interpolation point)", st->name, (long double)next_ut/1000000.0);
1101                 }
1102
1103                 st->last_updated.tv_sec = (time_t) (next_ut / 1000000ULL);
1104                 st->last_updated.tv_usec = 0;
1105
1106                 for( rd = st->dimensions ; likely(rd) ; rd = rd->next ) {
1107                         calculated_number new_value;
1108
1109                         switch(rd->algorithm) {
1110                                 case RRDDIM_INCREMENTAL:
1111                                         new_value = (calculated_number)
1112                                                 (          rd->calculated_value
1113                                                         * (calculated_number)(next_ut - last_ut)
1114                                                         / (calculated_number)(now_ut - last_ut)
1115                                                 );
1116
1117                                         if(unlikely(st->debug))
1118                                                 debug(D_RRD_STATS, "%s/%s: CALC2 INC "
1119                                                         CALCULATED_NUMBER_FORMAT " = "
1120                                                         CALCULATED_NUMBER_FORMAT
1121                                                         " * %llu"
1122                                                         " / %llu"
1123                                                         , st->id, rd->name
1124                                                         , new_value
1125                                                         , rd->calculated_value
1126                                                         , (next_ut - last_ut)
1127                                                         , (now_ut - last_ut)
1128                                                         );
1129
1130                                         rd->calculated_value -= new_value;
1131                                         new_value += rd->last_calculated_value;
1132                                         rd->last_calculated_value = 0;
1133                                         new_value /= (calculated_number)st->update_every;
1134                                         break;
1135
1136                                 case RRDDIM_ABSOLUTE:
1137                                 case RRDDIM_PCENT_OVER_ROW_TOTAL:
1138                                 case RRDDIM_PCENT_OVER_DIFF_TOTAL:
1139                                 default:
1140                                         if(iterations == 1) {
1141                                                 // this is the last iteration
1142                                                 // do not interpolate
1143                                                 // just show the calculated value
1144
1145                                                 new_value = rd->calculated_value;
1146                                         }
1147                                         else {
1148                                                 // we have missed an update
1149                                                 // interpolate in the middle values
1150
1151                                                 new_value = (calculated_number)
1152                                                         (       (         (rd->calculated_value - rd->last_calculated_value)
1153                                                                         * (calculated_number)(next_ut - first_ut)
1154                                                                         / (calculated_number)(now_ut - first_ut)
1155                                                                 )
1156                                                                 +  rd->last_calculated_value
1157                                                         );
1158
1159                                                 if(unlikely(st->debug))
1160                                                         debug(D_RRD_STATS, "%s/%s: CALC2 DEF "
1161                                                                 CALCULATED_NUMBER_FORMAT " = ((("
1162                                                                 "(" CALCULATED_NUMBER_FORMAT " - " CALCULATED_NUMBER_FORMAT ")"
1163                                                                 " * %llu"
1164                                                                 " / %llu) + " CALCULATED_NUMBER_FORMAT
1165                                                                 , st->id, rd->name
1166                                                                 , new_value
1167                                                                 , rd->calculated_value, rd->last_calculated_value
1168                                                                 , (next_ut - first_ut)
1169                                                                 , (now_ut - first_ut), rd->last_calculated_value
1170                                                                 );
1171
1172                                                 // this is wrong
1173                                                 // it fades the value towards the target
1174                                                 // while we know the calculated value is different
1175                                                 // if(likely(next_ut + st->update_every * 1000000ULL > now_ut)) rd->calculated_value = new_value;
1176                                         }
1177                                         break;
1178                         }
1179
1180                         if(unlikely(!store_this_entry)) {
1181                                 store_this_entry = 1;
1182                                 continue;
1183                         }
1184
1185                         if(likely(rd->updated && rd->counter > 1 && iterations < st->gap_when_lost_iterations_above)) {
1186                                 rd->values[st->current_entry] = pack_storage_number(new_value, storage_flags );
1187
1188                                 if(unlikely(st->debug))
1189                                         debug(D_RRD_STATS, "%s/%s: STORE[%ld] "
1190                                                 CALCULATED_NUMBER_FORMAT " = " CALCULATED_NUMBER_FORMAT
1191                                                 , st->id, rd->name
1192                                                 , st->current_entry
1193                                                 , unpack_storage_number(rd->values[st->current_entry]), new_value
1194                                                 );
1195                         }
1196                         else {
1197                                 if(unlikely(st->debug)) debug(D_RRD_STATS, "%s/%s: STORE[%ld] = NON EXISTING "
1198                                                 , st->id, rd->name
1199                                                 , st->current_entry
1200                                                 );
1201                                 rd->values[st->current_entry] = pack_storage_number(0, SN_NOT_EXISTS);
1202                         }
1203
1204                         stored_entries++;
1205
1206                         if(unlikely(st->debug)) {
1207                                 calculated_number t1 = new_value * (calculated_number)rd->multiplier / (calculated_number)rd->divisor;
1208                                 calculated_number t2 = unpack_storage_number(rd->values[st->current_entry]);
1209                                 calculated_number accuracy = accuracy_loss(t1, t2);
1210                                 debug(D_RRD_STATS, "%s/%s: UNPACK[%ld] = " CALCULATED_NUMBER_FORMAT " FLAGS=0x%08x (original = " CALCULATED_NUMBER_FORMAT ", accuracy loss = " CALCULATED_NUMBER_FORMAT "%%%s)"
1211                                                 , st->id, rd->name
1212                                                 , st->current_entry
1213                                                 , t2
1214                                                 , get_storage_number_flags(rd->values[st->current_entry])
1215                                                 , t1
1216                                                 , accuracy
1217                                                 , (accuracy > ACCURACY_LOSS) ? " **TOO BIG** " : ""
1218                                                 );
1219
1220                                 rd->collected_volume += t1;
1221                                 rd->stored_volume += t2;
1222                                 accuracy = accuracy_loss(rd->collected_volume, rd->stored_volume);
1223                                 debug(D_RRD_STATS, "%s/%s: VOLUME[%ld] = " CALCULATED_NUMBER_FORMAT ", calculated  = " CALCULATED_NUMBER_FORMAT ", accuracy loss = " CALCULATED_NUMBER_FORMAT "%%%s"
1224                                                 , st->id, rd->name
1225                                                 , st->current_entry
1226                                                 , rd->stored_volume
1227                                                 , rd->collected_volume
1228                                                 , accuracy
1229                                                 , (accuracy > ACCURACY_LOSS) ? " **TOO BIG** " : ""
1230                                                 );
1231
1232                         }
1233                 }
1234                 // reset the storage flags for the next point, if any;
1235                 storage_flags = SN_EXISTS;
1236
1237                 st->counter++;
1238                 st->current_entry = ((st->current_entry + 1) >= st->entries) ? 0 : st->current_entry + 1;
1239                 last_ut = next_ut;
1240         }
1241
1242         // align next interpolation to last collection point
1243         if(likely(stored_entries || !store_this_entry)) {
1244                 st->last_updated.tv_sec = st->last_collected_time.tv_sec;
1245                 st->last_updated.tv_usec = st->last_collected_time.tv_usec;
1246         }
1247
1248         for( rd = st->dimensions; likely(rd) ; rd = rd->next ) {
1249                 if(unlikely(!rd->updated)) continue;
1250
1251                 if(likely(stored_entries || !store_this_entry)) {
1252                         if(unlikely(st->debug)) debug(D_RRD_STATS, "%s/%s: setting last_collected_value (old: " COLLECTED_NUMBER_FORMAT ") to last_collected_value (new: " COLLECTED_NUMBER_FORMAT ")", st->id, rd->name, rd->last_collected_value, rd->collected_value);
1253                         rd->last_collected_value = rd->collected_value;
1254
1255                         if(unlikely(st->debug)) debug(D_RRD_STATS, "%s/%s: setting last_calculated_value (old: " CALCULATED_NUMBER_FORMAT ") to last_calculated_value (new: " CALCULATED_NUMBER_FORMAT ")", st->id, rd->name, rd->last_calculated_value, rd->calculated_value);
1256                         rd->last_calculated_value = rd->calculated_value;
1257                 }
1258
1259                 rd->calculated_value = 0;
1260                 rd->collected_value = 0;
1261                 rd->updated = 0;
1262
1263                 if(unlikely(st->debug)) debug(D_RRD_STATS, "%s/%s: END "
1264                         " last_collected_value = " COLLECTED_NUMBER_FORMAT
1265                         " collected_value = " COLLECTED_NUMBER_FORMAT
1266                         " last_calculated_value = " CALCULATED_NUMBER_FORMAT
1267                         " calculated_value = " CALCULATED_NUMBER_FORMAT
1268                         , st->id, rd->name
1269                         , rd->last_collected_value
1270                         , rd->collected_value
1271                         , rd->last_calculated_value
1272                         , rd->calculated_value
1273                         );
1274         }
1275         st->last_collected_total  = st->collected_total;
1276
1277         // ALL DONE ABOUT THE DATA UPDATE
1278         // --------------------------------------------------------------------
1279
1280         // find if there are any obsolete dimensions (not updated recently)
1281         if(unlikely(rrd_delete_unupdated_dimensions)) {
1282
1283                 for( rd = st->dimensions; likely(rd) ; rd = rd->next )
1284                         if((rd->last_collected_time.tv_sec + (rrd_delete_unupdated_dimensions * st->update_every)) < st->last_collected_time.tv_sec)
1285                                 break;
1286
1287                 if(unlikely(rd)) {
1288                         // there is dimension to free
1289                         // upgrade our read lock to a write lock
1290                         pthread_rwlock_unlock(&st->rwlock);
1291                         pthread_rwlock_wrlock(&st->rwlock);
1292
1293                         for( rd = st->dimensions, last = NULL ; likely(rd) ; ) {
1294                                 // remove it only it is not updated in rrd_delete_unupdated_dimensions seconds
1295
1296                                 if(unlikely((rd->last_collected_time.tv_sec + (rrd_delete_unupdated_dimensions * st->update_every)) < st->last_collected_time.tv_sec)) {
1297                                         info("Removing obsolete dimension '%s' (%s) of '%s' (%s).", rd->name, rd->id, st->name, st->id);
1298
1299                                         if(unlikely(!last)) {
1300                                                 st->dimensions = rd->next;
1301                                                 rd->next = NULL;
1302                                                 rrddim_free(st, rd);
1303                                                 rd = st->dimensions;
1304                                                 continue;
1305                                         }
1306                                         else {
1307                                                 last->next = rd->next;
1308                                                 rd->next = NULL;
1309                                                 rrddim_free(st, rd);
1310                                                 rd = last->next;
1311                                                 continue;
1312                                         }
1313                                 }
1314
1315                                 last = rd;
1316                                 rd = rd->next;
1317                         }
1318
1319                         if(unlikely(!st->dimensions)) {
1320                                 info("Disabling chart %s (%s) since it does not have any dimensions", st->name, st->id);
1321                                 st->enabled = 0;
1322                         }
1323                 }
1324         }
1325
1326         pthread_rwlock_unlock(&st->rwlock);
1327
1328         if(unlikely(pthread_setcancelstate(oldstate, NULL) != 0))
1329                 error("Cannot set pthread cancel state to RESTORE (%d).", oldstate);
1330
1331         return(st->usec_since_last_update);
1332 }