src/backends.c

   1 #include "common.h"
   2
   3 #define BACKEND_SOURCE_DATA_AS_COLLECTED 0x00000001
   4 #define BACKEND_SOURCE_DATA_AVERAGE      0x00000002
   5 #define BACKEND_SOURCE_DATA_SUM          0x00000004
   6
   7 static inline calculated_number backend_calculate_value_from_stored_data(RRDSET *st, RRDDIM *rd, time_t after, time_t before, uint32_t options) {
   8     time_t first_t = rrdset_first_entry_t(st);
   9     time_t last_t = rrdset_last_entry_t(st);
  10
  11     if(unlikely(before < first_t || after > last_t))
  12         // the chart has not been updated in the wanted timeframe
  13         return NAN;
  14
  15     // align the time-frame
  16     // for 'after' also skip the first value by adding st->update_every
  17     after  = after  - after  % st->update_every + st->update_every;
  18     before = before - before % st->update_every;
  19
  20     if(unlikely(after < first_t))
  21         after = first_t;
  22
  23     if(unlikely(after > before))
  24         // this can happen when the st->update_every > before - after
  25         before = after;
  26
  27     if(unlikely(before > last_t))
  28         before = last_t;
  29
  30     size_t counter = 0;
  31     calculated_number sum = 0;
  32
  33     long    start_at_slot = rrdset_time2slot(st, before),
  34             stop_at_slot  = rrdset_time2slot(st, after),
  35             slot, stop_now = 0;
  36
  37     for(slot = start_at_slot; !stop_now ; slot--) {
  38         if(unlikely(slot < 0)) slot = st->entries - 1;
  39         if(unlikely(slot == stop_at_slot)) stop_now = 1;
  40
  41         storage_number n = rd->values[slot];
  42         if(unlikely(!does_storage_number_exist(n))) continue;
  43
  44         calculated_number value = unpack_storage_number(n);
  45         sum += value;
  46         counter++;
  47     }
  48
  49     if(unlikely(!counter))
  50         return NAN;
  51
  52     if(unlikely(options & BACKEND_SOURCE_DATA_SUM))
  53         return sum;
  54
  55     return sum / (calculated_number)counter;
  56 }
  57
  58 static inline int format_dimension_collected_graphite_plaintext(BUFFER *b, const char *prefix, RRDHOST *host, const char *hostname, RRDSET *st, RRDDIM *rd, time_t after, time_t before, uint32_t options) {
  59     (void)host;
  60     (void)after;
  61     (void)before;
  62     (void)options;
  63     buffer_sprintf(b, "%s.%s.%s.%s " COLLECTED_NUMBER_FORMAT " %u\n", prefix, hostname, st->id, rd->id, rd->last_collected_value, (uint32_t)rd->last_collected_time.tv_sec);
  64     return 1;
  65 }
  66
  67 static inline int format_dimension_stored_graphite_plaintext(BUFFER *b, const char *prefix, RRDHOST *host, const char *hostname, RRDSET *st, RRDDIM *rd, time_t after, time_t before, uint32_t options) {
  68     (void)host;
  69     calculated_number value = backend_calculate_value_from_stored_data(st, rd, after, before, options);
  70     if(!isnan(value)) {
  71         buffer_sprintf(b, "%s.%s.%s.%s " CALCULATED_NUMBER_FORMAT " %u\n", prefix, hostname, st->id, rd->id, value, (uint32_t) before);
  72         return 1;
  73     }
  74     return 0;
  75 }
  76
  77 static inline int format_dimension_collected_opentsdb_telnet(BUFFER *b, const char *prefix, RRDHOST *host, const char *hostname, RRDSET *st, RRDDIM *rd, time_t after, time_t before, uint32_t options) {
  78     (void)host;
  79     (void)after;
  80     (void)before;
  81     (void)options;
  82     buffer_sprintf(b, "put %s.%s.%s %u " COLLECTED_NUMBER_FORMAT " host=%s\n", prefix, st->id, rd->id, (uint32_t)rd->last_collected_time.tv_sec, rd->last_collected_value, hostname);
  83     return 1;
  84 }
  85
  86 static inline int format_dimension_stored_opentsdb_telnet(BUFFER *b, const char *prefix, RRDHOST *host, const char *hostname, RRDSET *st, RRDDIM *rd, time_t after, time_t before, uint32_t options) {
  87     (void)host;
  88     calculated_number value = backend_calculate_value_from_stored_data(st, rd, after, before, options);
  89     if(!isnan(value)) {
  90         buffer_sprintf(b, "put %s.%s.%s %u " CALCULATED_NUMBER_FORMAT " host=%s\n", prefix, st->id, rd->id, (uint32_t) before, value, hostname);
  91         return 1;
  92     }
  93     return 0;
  94 }
  95
  96 static inline int format_dimension_collected_json_plaintext(BUFFER *b, const char *prefix, RRDHOST *host, const char *hostname, RRDSET *st, RRDDIM *rd, time_t after, time_t before, uint32_t options) {
  97     (void)host;
  98     (void)after;
  99     (void)before;
 100     (void)options;
 101     buffer_sprintf(b, "{"
 102         "\"prefix\":\"%s\","
 103         "\"hostname\":\"%s\","
 104
 105         "\"chart_id\":\"%s\","
 106         "\"chart_name\":\"%s\","
 107         "\"family\":\"%s\","
 108         "\"context\": \"%s\","
 109         "\"type\":\"%s\","
 110         "\"units\": \"%s\","
 111
 112         "\"id\":\"%s\","
 113         "\"name\":\"%s\","
 114         "\"value\":" COLLECTED_NUMBER_FORMAT ","
 115
 116         "\"timestamp\": %u}\n",
 117             prefix,
 118             hostname,
 119
 120             st->id,
 121             st->name,
 122             st->family,
 123             st->context,
 124             st->type,
 125             st->units,
 126
 127             rd->id,
 128             rd->name,
 129             rd->last_collected_value,
 130
 131             (uint32_t)rd->last_collected_time.tv_sec
 132     );
 133
 134     return 1;
 135 }
 136
 137 static inline int format_dimension_stored_json_plaintext(BUFFER *b, const char *prefix, RRDHOST *host, const char *hostname, RRDSET *st, RRDDIM *rd, time_t after, time_t before, uint32_t options) {
 138     (void)host;
 139     calculated_number value = backend_calculate_value_from_stored_data(st, rd, after, before, options);
 140     if(!isnan(value)) {
 141         buffer_sprintf(b, "{"
 142             "\"prefix\":\"%s\","
 143             "\"hostname\":\"%s\","
 144
 145             "\"chart_id\":\"%s\","
 146             "\"chart_name\":\"%s\","
 147             "\"family\":\"%s\","
 148             "\"context\": \"%s\","
 149             "\"type\":\"%s\","
 150             "\"units\": \"%s\","
 151
 152             "\"id\":\"%s\","
 153             "\"name\":\"%s\","
 154             "\"value\":" CALCULATED_NUMBER_FORMAT ","
 155
 156             "\"timestamp\": %u}\n",
 157                 prefix,
 158                 hostname,
 159
 160                 st->id,
 161                 st->name,
 162                 st->family,
 163                 st->context,
 164                 st->type,
 165                 st->units,
 166
 167                 rd->id,
 168                 rd->name,
 169                 value,
 170
 171                 (uint32_t)before
 172         );
 173
 174         return 1;
 175     }
 176     return 0;
 177 }
 178
 179 static inline int process_graphite_response(BUFFER *b) {
 180     char sample[1024];
 181     const char *s = buffer_tostring(b);
 182     char *d = sample, *e = &sample[sizeof(sample) - 1];
 183
 184     for(; *s && d < e ;s++) {
 185         char c = *s;
 186         if(unlikely(!isprint(c))) c = ' ';
 187         *d++ = c;
 188     }
 189     *d = '\0';
 190
 191     info("Received %zu bytes from graphite backend. Ignoring them. Sample: '%s'", buffer_strlen(b), sample);
 192     buffer_flush(b);
 193     return 0;
 194 }
 195
 196 static inline int process_json_response(BUFFER *b) {
 197     char sample[1024];
 198     const char *s = buffer_tostring(b);
 199     char *d = sample, *e = &sample[sizeof(sample) - 1];
 200
 201     for(; *s && d < e ;s++) {
 202         char c = *s;
 203         if(unlikely(!isprint(c))) c = ' ';
 204         *d++ = c;
 205     }
 206     *d = '\0';
 207
 208     info("Received %zu bytes from json backend. Ignoring them. Sample: '%s'", buffer_strlen(b), sample);
 209     buffer_flush(b);
 210     return 0;
 211 }
 212
 213 static inline int process_opentsdb_response(BUFFER *b) {
 214     char sample[1024];
 215     const char *s = buffer_tostring(b);
 216     char *d = sample, *e = &sample[sizeof(sample) - 1];
 217
 218     for(; *s && d < e ;s++) {
 219         char c = *s;
 220         if(unlikely(!isprint(c))) c = ' ';
 221         *d++ = c;
 222     }
 223     *d = '\0';
 224
 225     info("Received %zu bytes from opentsdb backend. Ignoring them. Sample: '%s'", buffer_strlen(b), sample);
 226     buffer_flush(b);
 227     return 0;
 228 }
 229
 230 void *backends_main(void *ptr) {
 231     int default_port = 0;
 232     int sock = -1;
 233     struct netdata_static_thread *static_thread = (struct netdata_static_thread *)ptr;
 234
 235     BUFFER *b = buffer_create(1), *response = buffer_create(1);
 236     int (*backend_request_formatter)(BUFFER *, const char *, RRDHOST *, const char *, RRDSET *, RRDDIM *, time_t, time_t, uint32_t) = NULL;
 237     int (*backend_response_checker)(BUFFER *) = NULL;
 238
 239     info("BACKEND thread created with task id %d", gettid());
 240
 241     if(pthread_setcanceltype(PTHREAD_CANCEL_DEFERRED, NULL) != 0)
 242         error("Cannot set pthread cancel type to DEFERRED.");
 243
 244     if(pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL) != 0)
 245         error("Cannot set pthread cancel state to ENABLE.");
 246
 247     // ------------------------------------------------------------------------
 248     // collect configuration options
 249
 250     struct timeval timeout = {
 251             .tv_sec = 0,
 252             .tv_usec = 0
 253     };
 254     uint32_t options;
 255     int enabled             = config_get_boolean(CONFIG_SECTION_BACKEND, "enabled", 0);
 256     const char *source      = config_get(CONFIG_SECTION_BACKEND, "data source", "average");
 257     const char *type        = config_get(CONFIG_SECTION_BACKEND, "type", "graphite");
 258     const char *destination = config_get(CONFIG_SECTION_BACKEND, "destination", "localhost");
 259     const char *prefix      = config_get(CONFIG_SECTION_BACKEND, "prefix", "netdata");
 260     const char *hostname    = config_get(CONFIG_SECTION_BACKEND, "hostname", localhost->hostname);
 261     int frequency           = (int)config_get_number(CONFIG_SECTION_BACKEND, "update every", 10);
 262     int buffer_on_failures  = (int)config_get_number(CONFIG_SECTION_BACKEND, "buffer on failures", 10);
 263     long timeoutms          = config_get_number(CONFIG_SECTION_BACKEND, "timeout ms", frequency * 2 * 1000);
 264
 265     // ------------------------------------------------------------------------
 266     // validate configuration options
 267     // and prepare for sending data to our backend
 268
 269     if(!enabled || frequency < 1)
 270         goto cleanup;
 271
 272     if(!strcmp(source, "as collected")) {
 273         options = BACKEND_SOURCE_DATA_AS_COLLECTED;
 274     }
 275     else if(!strcmp(source, "average")) {
 276         options = BACKEND_SOURCE_DATA_AVERAGE;
 277     }
 278     else if(!strcmp(source, "sum") || !strcmp(source, "volume")) {
 279         options = BACKEND_SOURCE_DATA_SUM;
 280     }
 281     else {
 282         error("Invalid data source method '%s' for backend given. Disabling backed.", source);
 283         goto cleanup;
 284     }
 285
 286     if(timeoutms < 1) {
 287         error("BACKED invalid timeout %ld ms given. Assuming %d ms.", timeoutms, frequency * 2 * 1000);
 288         timeoutms = frequency * 2 * 1000;
 289     }
 290     timeout.tv_sec  = (timeoutms * 1000) / 1000000;
 291     timeout.tv_usec = (timeoutms * 1000) % 1000000;
 292
 293
 294     // ------------------------------------------------------------------------
 295     // select the backend type
 296
 297     if(!strcmp(type, "graphite") || !strcmp(type, "graphite:plaintext")) {
 298         default_port = 2003;
 299         if(options == BACKEND_SOURCE_DATA_AS_COLLECTED)
 300             backend_request_formatter = format_dimension_collected_graphite_plaintext;
 301         else
 302             backend_request_formatter = format_dimension_stored_graphite_plaintext;
 303
 304         backend_response_checker = process_graphite_response;
 305     }
 306     else if(!strcmp(type, "opentsdb") || !strcmp(type, "opentsdb:telnet")) {
 307         default_port = 4242;
 308         if(options == BACKEND_SOURCE_DATA_AS_COLLECTED)
 309             backend_request_formatter = format_dimension_collected_opentsdb_telnet;
 310         else
 311             backend_request_formatter = format_dimension_stored_opentsdb_telnet;
 312
 313         backend_response_checker = process_opentsdb_response;
 314     }
 315     else if (!strcmp(type, "json") || !strcmp(type, "json:plaintext"))
 316     {
 317         default_port = 5448;
 318
 319         if (options == BACKEND_SOURCE_DATA_AS_COLLECTED)
 320         {
 321             backend_request_formatter = format_dimension_collected_json_plaintext;
 322         }
 323         else
 324         {
 325             backend_request_formatter = format_dimension_stored_json_plaintext;
 326         }
 327
 328         backend_response_checker = process_json_response;
 329     }
 330     else {
 331         error("Unknown backend type '%s'", type);
 332         goto cleanup;
 333     }
 334
 335     if(backend_request_formatter == NULL || backend_response_checker == NULL) {
 336         error("backend is misconfigured - disabling it.");
 337         goto cleanup;
 338     }
 339
 340
 341     // ------------------------------------------------------------------------
 342     // prepare the charts for monitoring the backend operation
 343
 344     struct rusage thread;
 345
 346     collected_number
 347             chart_buffered_metrics = 0,
 348             chart_lost_metrics = 0,
 349             chart_sent_metrics = 0,
 350             chart_buffered_bytes = 0,
 351             chart_received_bytes = 0,
 352             chart_sent_bytes = 0,
 353             chart_receptions = 0,
 354             chart_transmission_successes = 0,
 355             chart_transmission_failures = 0,
 356             chart_data_lost_events = 0,
 357             chart_lost_bytes = 0,
 358             chart_backend_reconnects = 0,
 359             chart_backend_latency = 0;
 360
 361     RRDSET *chart_metrics = rrdset_create_localhost("netdata", "backend_metrics", NULL, "backend", NULL, "Netdata Buffered Metrics", "metrics", 130600, frequency, RRDSET_TYPE_LINE);
 362     rrddim_add(chart_metrics, "buffered", NULL,  1, 1, RRD_ALGORITHM_ABSOLUTE);
 363     rrddim_add(chart_metrics, "lost",     NULL,  1, 1, RRD_ALGORITHM_ABSOLUTE);
 364     rrddim_add(chart_metrics, "sent",     NULL,  1, 1, RRD_ALGORITHM_ABSOLUTE);
 365
 366     RRDSET *chart_bytes = rrdset_create_localhost("netdata", "backend_bytes", NULL, "backend", NULL, "Netdata Backend Data Size", "KB", 130610, frequency, RRDSET_TYPE_AREA);
 367     rrddim_add(chart_bytes, "buffered", NULL, 1, 1024, RRD_ALGORITHM_ABSOLUTE);
 368     rrddim_add(chart_bytes, "lost",     NULL, 1, 1024, RRD_ALGORITHM_ABSOLUTE);
 369     rrddim_add(chart_bytes, "sent",     NULL, 1, 1024, RRD_ALGORITHM_ABSOLUTE);
 370     rrddim_add(chart_bytes, "received", NULL, 1, 1024, RRD_ALGORITHM_ABSOLUTE);
 371
 372     RRDSET *chart_ops = rrdset_create_localhost("netdata", "backend_ops", NULL, "backend", NULL, "Netdata Backend Operations", "operations", 130630, frequency, RRDSET_TYPE_LINE);
 373     rrddim_add(chart_ops, "write",     NULL, 1, 1, RRD_ALGORITHM_ABSOLUTE);
 374     rrddim_add(chart_ops, "discard",   NULL, 1, 1, RRD_ALGORITHM_ABSOLUTE);
 375     rrddim_add(chart_ops, "reconnect", NULL, 1, 1, RRD_ALGORITHM_ABSOLUTE);
 376     rrddim_add(chart_ops, "failure",   NULL, 1, 1, RRD_ALGORITHM_ABSOLUTE);
 377     rrddim_add(chart_ops, "read",      NULL, 1, 1, RRD_ALGORITHM_ABSOLUTE);
 378
 379     /*
 380      * this is misleading - we can only measure the time we need to send data
 381      * this time is not related to the time required for the data to travel to
 382      * the backend database and the time that server needed to process them
 383      *
 384      * issue #1432 and https://www.softlab.ntua.gr/facilities/documentation/unix/unix-socket-faq/unix-socket-faq-2.html
 385      *
 386     RRDSET *chart_latency = rrdset_create_localhost("netdata", "backend_latency", NULL, "backend", NULL, "Netdata Backend Latency", "ms", 130620, frequency, RRDSET_TYPE_AREA);
 387     rrddim_add(chart_latency, "latency",   NULL,  1, 1000, RRD_ALGORITHM_ABSOLUTE);
 388     */
 389
 390     RRDSET *chart_rusage = rrdset_create_localhost("netdata", "backend_thread_cpu", NULL, "backend", NULL, "NetData Backend Thread CPU usage", "milliseconds/s", 130630, frequency, RRDSET_TYPE_STACKED);
 391     rrddim_add(chart_rusage, "user",   NULL, 1, 1000, RRD_ALGORITHM_INCREMENTAL);
 392     rrddim_add(chart_rusage, "system", NULL, 1, 1000, RRD_ALGORITHM_INCREMENTAL);
 393
 394
 395     // ------------------------------------------------------------------------
 396     // prepare the backend main loop
 397
 398     info("BACKEND configured ('%s' on '%s' sending '%s' data, every %d seconds, as host '%s', with prefix '%s')", type, destination, source, frequency, hostname, prefix);
 399
 400     usec_t step_ut = frequency * USEC_PER_SEC;
 401     time_t after = now_realtime_sec();
 402     int failures = 0;
 403     heartbeat_t hb;
 404     heartbeat_init(&hb);
 405
 406     for(;;) {
 407
 408         // ------------------------------------------------------------------------
 409         // Wait for the next iteration point.
 410         heartbeat_next(&hb, step_ut);
 411         time_t before = now_realtime_sec();
 412
 413
 414         // ------------------------------------------------------------------------
 415         // add to the buffer the data we need to send to the backend
 416
 417         int pthreadoldcancelstate;
 418
 419         if(unlikely(pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &pthreadoldcancelstate) != 0))
 420             error("Cannot set pthread cancel state to DISABLE.");
 421
 422         rrd_rdlock();
 423         RRDHOST *host;
 424         rrdhost_foreach_read(host) {
 425             if(host->rrd_memory_mode == RRD_MEMORY_MODE_NONE)
 426                 continue;
 427
 428             rrdhost_rdlock(host);
 429
 430             RRDSET *st;
 431             rrdset_foreach_read(st, host) {
 432                 rrdset_rdlock(st);
 433
 434                 RRDDIM *rd;
 435                 rrddim_foreach_read(rd, st) {
 436                     if(rd->last_collected_time.tv_sec >= after)
 437                         chart_buffered_metrics += backend_request_formatter(b, prefix, host, (host == localhost)?hostname:host->hostname, st, rd, after, before, options);
 438                 }
 439                 rrdset_unlock(st);
 440             }
 441             rrdhost_unlock(host);
 442         }
 443         rrd_unlock();
 444
 445         if(unlikely(pthread_setcancelstate(pthreadoldcancelstate, NULL) != 0))
 446             error("Cannot set pthread cancel state to RESTORE (%d).", pthreadoldcancelstate);
 447
 448         // ------------------------------------------------------------------------
 449
 450         chart_buffered_bytes = (collected_number)buffer_strlen(b);
 451
 452         // reset the monitoring chart counters
 453         chart_received_bytes =
 454         chart_sent_bytes =
 455         chart_sent_metrics =
 456         chart_lost_metrics =
 457         chart_transmission_successes =
 458         chart_transmission_failures =
 459         chart_data_lost_events =
 460         chart_lost_bytes =
 461         chart_backend_reconnects =
 462         chart_backend_latency = 0;
 463
 464         if(unlikely(netdata_exit)) break;
 465
 466         //fprintf(stderr, "\nBACKEND BEGIN:\n%s\nBACKEND END\n", buffer_tostring(b)); // FIXME
 467         //fprintf(stderr, "after = %lu, before = %lu\n", after, before);
 468
 469         // prepare for the next iteration
 470         // to add incrementally data to buffer
 471         after = before;
 472
 473         // ------------------------------------------------------------------------
 474         // if we are connected, receive a response, without blocking
 475
 476         if(likely(sock != -1)) {
 477             errno = 0;
 478
 479             // loop through to collect all data
 480             while(sock != -1 && errno != EWOULDBLOCK) {
 481                 buffer_need_bytes(response, 4096);
 482
 483                 ssize_t r = recv(sock, &response->buffer[response->len], response->size - response->len, MSG_DONTWAIT);
 484                 if(likely(r > 0)) {
 485                     // we received some data
 486                     response->len += r;
 487                     chart_received_bytes += r;
 488                     chart_receptions++;
 489                 }
 490                 else if(r == 0) {
 491                     error("Backend '%s' closed the socket", destination);
 492                     close(sock);
 493                     sock = -1;
 494                 }
 495                 else {
 496                     // failed to receive data
 497                     if(errno != EAGAIN && errno != EWOULDBLOCK) {
 498                         error("Cannot receive data from backend '%s'.", destination);
 499                     }
 500                 }
 501             }
 502
 503             // if we received data, process them
 504             if(buffer_strlen(response))
 505                 backend_response_checker(response);
 506         }
 507
 508         // ------------------------------------------------------------------------
 509         // if we are not connected, connect to a backend server
 510
 511         if(unlikely(sock == -1)) {
 512             usec_t start_ut = now_monotonic_usec();
 513             size_t reconnects = 0;
 514
 515             sock = connect_to_one_of(destination, default_port, &timeout, &reconnects, NULL, 0);
 516
 517             chart_backend_reconnects += reconnects;
 518             chart_backend_latency += now_monotonic_usec() - start_ut;
 519         }
 520
 521         if(unlikely(netdata_exit)) break;
 522
 523         // ------------------------------------------------------------------------
 524         // if we are connected, send our buffer to the backend server
 525
 526         if(likely(sock != -1)) {
 527             size_t len = buffer_strlen(b);
 528             usec_t start_ut = now_monotonic_usec();
 529             int flags = 0;
 530 #ifdef MSG_NOSIGNAL
 531             flags += MSG_NOSIGNAL;
 532 #endif
 533
 534             ssize_t written = send(sock, buffer_tostring(b), len, flags);
 535             chart_backend_latency += now_monotonic_usec() - start_ut;
 536             if(written != -1 && (size_t)written == len) {
 537                 // we sent the data successfully
 538                 chart_transmission_successes++;
 539                 chart_sent_bytes += written;
 540                 chart_sent_metrics = chart_buffered_metrics;
 541
 542                 // reset the failures count
 543                 failures = 0;
 544
 545                 // empty the buffer
 546                 buffer_flush(b);
 547             }
 548             else {
 549                 // oops! we couldn't send (all or some of the) data
 550                 error("Failed to write data to database backend '%s'. Willing to write %zu bytes, wrote %zd bytes. Will re-connect.", destination, len, written);
 551                 chart_transmission_failures++;
 552
 553                 if(written != -1)
 554                     chart_sent_bytes += written;
 555
 556                 // increment the counter we check for data loss
 557                 failures++;
 558
 559                 // close the socket - we will re-open it next time
 560                 close(sock);
 561                 sock = -1;
 562             }
 563         }
 564         else {
 565             error("Failed to update database backend '%s'", destination);
 566             chart_transmission_failures++;
 567
 568             // increment the counter we check for data loss
 569             failures++;
 570         }
 571
 572         if(failures > buffer_on_failures) {
 573             // too bad! we are going to lose data
 574             chart_lost_bytes += buffer_strlen(b);
 575             error("Reached %d backend failures. Flushing buffers to protect this host - this results in data loss on back-end server '%s'", failures, destination);
 576             buffer_flush(b);
 577             failures = 0;
 578             chart_data_lost_events++;
 579             chart_lost_metrics = chart_buffered_metrics;
 580         }
 581
 582         if(unlikely(netdata_exit)) break;
 583
 584         // ------------------------------------------------------------------------
 585         // update the monitoring charts
 586
 587         if(likely(chart_ops->counter_done)) rrdset_next(chart_ops);
 588         rrddim_set(chart_ops, "read",         chart_receptions);
 589         rrddim_set(chart_ops, "write",        chart_transmission_successes);
 590         rrddim_set(chart_ops, "discard",      chart_data_lost_events);
 591         rrddim_set(chart_ops, "failure",      chart_transmission_failures);
 592         rrddim_set(chart_ops, "reconnect",    chart_backend_reconnects);
 593         rrdset_done(chart_ops);
 594
 595         if(likely(chart_metrics->counter_done)) rrdset_next(chart_metrics);
 596         rrddim_set(chart_metrics, "buffered", chart_buffered_metrics);
 597         rrddim_set(chart_metrics, "lost",     chart_lost_metrics);
 598         rrddim_set(chart_metrics, "sent",     chart_sent_metrics);
 599         rrdset_done(chart_metrics);
 600
 601         if(likely(chart_bytes->counter_done)) rrdset_next(chart_bytes);
 602         rrddim_set(chart_bytes, "buffered",   chart_buffered_bytes);
 603         rrddim_set(chart_bytes, "lost",       chart_lost_bytes);
 604         rrddim_set(chart_bytes, "sent",       chart_sent_bytes);
 605         rrddim_set(chart_bytes, "received",   chart_received_bytes);
 606         rrdset_done(chart_bytes);
 607
 608         /*
 609         if(likely(chart_latency->counter_done)) rrdset_next(chart_latency);
 610         rrddim_set(chart_latency, "latency",  chart_backend_latency);
 611         rrdset_done(chart_latency);
 612         */
 613
 614         getrusage(RUSAGE_THREAD, &thread);
 615         if(likely(chart_rusage->counter_done)) rrdset_next(chart_rusage);
 616         rrddim_set(chart_rusage, "user",   thread.ru_utime.tv_sec * 1000000ULL + thread.ru_utime.tv_usec);
 617         rrddim_set(chart_rusage, "system", thread.ru_stime.tv_sec * 1000000ULL + thread.ru_stime.tv_usec);
 618         rrdset_done(chart_rusage);
 619
 620         if(likely(buffer_strlen(b) == 0))
 621             chart_buffered_metrics = 0;
 622
 623         if(unlikely(netdata_exit)) break;
 624     }
 625
 626 cleanup:
 627     if(sock != -1)
 628         close(sock);
 629
 630     buffer_free(b);
 631     buffer_free(response);
 632
 633     info("BACKEND thread exiting");
 634
 635     static_thread->enabled = 0;
 636     pthread_exit(NULL);
 637     return NULL;
 638 }