src/plugin_idlejitter.c

   1 #include <pthread.h>
   2 #include <sys/time.h>
   3 #include <sys/resource.h>
   4 #include <strings.h>
   5 #include <unistd.h>
   6
   7 #include "global_statistics.h"
   8 #include "common.h"
   9 #include "config.h"
  10 #include "log.h"
  11 #include "rrd.h"
  12 #include "plugin_idlejitter.h"
  13
  14 #define CPU_IDLEJITTER_SLEEP_TIME_MS 20
  15
  16 void *cpuidlejitter_main(void *ptr)
  17 {
  18         if(ptr) { ; }
  19
  20         info("CPU Idle Jitter thread created with task id %d", gettid());
  21
  22         if(pthread_setcanceltype(PTHREAD_CANCEL_DEFERRED, NULL) != 0)
  23                 error("Cannot set pthread cancel type to DEFERRED.");
  24
  25         if(pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL) != 0)
  26                 error("Cannot set pthread cancel state to ENABLE.");
  27
  28         int sleep_ms = config_get_number("plugin:idlejitter", "loop time in ms", CPU_IDLEJITTER_SLEEP_TIME_MS);
  29         if(sleep_ms <= 0) {
  30                 config_set_number("plugin:idlejitter", "loop time in ms", CPU_IDLEJITTER_SLEEP_TIME_MS);
  31                 sleep_ms = CPU_IDLEJITTER_SLEEP_TIME_MS;
  32         }
  33
  34         RRDSET *st = rrdset_find("system.idlejitter");
  35         if(!st) {
  36                 st = rrdset_create("system", "idlejitter", NULL, "cpu", "CPU Idle Jitter", "microseconds lost/s", 9999, rrd_update_every, RRDSET_TYPE_LINE);
  37                 rrddim_add(st, "jitter", NULL, 1, 1, RRDDIM_ABSOLUTE);
  38         }
  39
  40         struct timeval before, after;
  41         unsigned long long counter;
  42         for(counter = 0; 1 ;counter++) {
  43                 unsigned long long usec = 0, susec = 0;
  44
  45                 while(susec < (rrd_update_every * 1000000ULL)) {
  46
  47                         gettimeofday(&before, NULL);
  48                         usleep(sleep_ms * 1000);
  49                         gettimeofday(&after, NULL);
  50
  51                         // calculate the time it took for a full loop
  52                         usec = usecdiff(&after, &before);
  53                         susec += usec;
  54                 }
  55                 usec -= (sleep_ms * 1000);
  56
  57                 if(counter) rrdset_next_usec(st, susec);
  58                 rrddim_set(st, "jitter", usec);
  59                 rrdset_done(st);
  60         }
  61
  62         return NULL;
  63 }
  64