src/plugin_idlejitter.c

   1 #include "common.h"
   2
   3 #define CPU_IDLEJITTER_SLEEP_TIME_MS 20
   4
   5 void *cpuidlejitter_main(void *ptr) {
   6     struct netdata_static_thread *static_thread = (struct netdata_static_thread *)ptr;
   7
   8     info("IDLEJITTER thread created with task id %d", gettid());
   9
  10     if(pthread_setcanceltype(PTHREAD_CANCEL_DEFERRED, NULL) != 0)
  11         error("Cannot set pthread cancel type to DEFERRED.");
  12
  13     if(pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL) != 0)
  14         error("Cannot set pthread cancel state to ENABLE.");
  15
  16     int sleep_ms = (int) config_get_number("plugin:idlejitter", "loop time in ms", CPU_IDLEJITTER_SLEEP_TIME_MS);
  17     if(sleep_ms <= 0) {
  18         config_set_number("plugin:idlejitter", "loop time in ms", CPU_IDLEJITTER_SLEEP_TIME_MS);
  19         sleep_ms = CPU_IDLEJITTER_SLEEP_TIME_MS;
  20     }
  21
  22     RRDSET *st = rrdset_find_localhost("system.idlejitter");
  23     if(!st) {
  24         st = rrdset_create_localhost("system", "idlejitter", NULL, "processes", NULL, "CPU Idle Jitter"
  25                                      , "microseconds lost/s", 9999, localhost->rrd_update_every, RRDSET_TYPE_LINE);
  26         rrddim_add(st, "jitter", NULL, 1, 1, RRD_ALGORITHM_ABSOLUTE);
  27     }
  28
  29     struct timeval before, after;
  30     unsigned long long counter;
  31     for(counter = 0; 1 ;counter++) {
  32         usec_t usec = 0, susec = 0;
  33
  34         while(susec < (localhost->rrd_update_every * USEC_PER_SEC)) {
  35
  36             now_monotonic_timeval(&before);
  37             sleep_usec(sleep_ms * 1000);
  38             now_monotonic_timeval(&after);
  39
  40             // calculate the time it took for a full loop
  41             usec = dt_usec(&after, &before);
  42             susec += usec;
  43         }
  44         usec -= (sleep_ms * 1000);
  45
  46         if(counter) rrdset_next(st);
  47         rrddim_set(st, "jitter", usec);
  48         rrdset_done(st);
  49     }
  50
  51     info("IDLEJITTER thread exiting");
  52
  53     static_thread->enabled = 0;
  54     pthread_exit(NULL);
  55     return NULL;
  56 }
  57