test-timers.c 3.8 KB

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  1. /* Copyright 2016-2018, The Tor Project, Inc. */
  2. /* See LICENSE for licensing information */
  3. #include "orconfig.h"
  4. #include <math.h>
  5. #include <stdio.h>
  6. #include <string.h>
  7. #include "common/compat.h"
  8. #include "common/compat_libevent.h"
  9. #include "common/crypto_rand.h"
  10. #include "common/timers.h"
  11. #include "common/util.h"
  12. #define N_TIMERS 1000
  13. #define MAX_DURATION 30
  14. #define N_DISABLE 5
  15. static struct timeval fire_at[N_TIMERS] = { {0,0} };
  16. static int is_disabled[N_TIMERS] = {0};
  17. static int fired[N_TIMERS] = {0};
  18. static struct timeval difference[N_TIMERS] = { {0,0} };
  19. static tor_timer_t *timers[N_TIMERS] = {NULL};
  20. static int n_active_timers = 0;
  21. static int n_fired = 0;
  22. static monotime_t started_at;
  23. static int64_t delay_usec[N_TIMERS];
  24. static int64_t diffs_mono_usec[N_TIMERS];
  25. static void
  26. timer_cb(tor_timer_t *t, void *arg, const monotime_t *now_mono)
  27. {
  28. struct timeval now;
  29. tor_gettimeofday(&now);
  30. tor_timer_t **t_ptr = arg;
  31. tor_assert(*t_ptr == t);
  32. int idx = (int) (t_ptr - timers);
  33. ++fired[idx];
  34. timersub(&now, &fire_at[idx], &difference[idx]);
  35. diffs_mono_usec[idx] =
  36. monotime_diff_usec(&started_at, now_mono) -
  37. delay_usec[idx];
  38. ++n_fired;
  39. // printf("%d / %d\n",n_fired, N_TIMERS);
  40. if (n_fired == n_active_timers) {
  41. tor_libevent_exit_loop_after_callback(tor_libevent_get_base());
  42. }
  43. }
  44. int
  45. main(int argc, char **argv)
  46. {
  47. (void)argc;
  48. (void)argv;
  49. tor_libevent_cfg cfg;
  50. memset(&cfg, 0, sizeof(cfg));
  51. tor_libevent_initialize(&cfg);
  52. timers_initialize();
  53. int i;
  54. int ret;
  55. struct timeval now;
  56. tor_gettimeofday(&now);
  57. monotime_get(&started_at);
  58. for (i = 0; i < N_TIMERS; ++i) {
  59. struct timeval delay;
  60. delay.tv_sec = crypto_rand_int_range(0,MAX_DURATION);
  61. delay.tv_usec = crypto_rand_int_range(0,1000000);
  62. delay_usec[i] = delay.tv_sec * 1000000 + delay.tv_usec;
  63. timeradd(&now, &delay, &fire_at[i]);
  64. timers[i] = timer_new(timer_cb, &timers[i]);
  65. timer_schedule(timers[i], &delay);
  66. ++n_active_timers;
  67. }
  68. /* Disable some; we'll make sure they don't trigger. */
  69. for (i = 0; i < N_DISABLE; ++i) {
  70. int idx = crypto_rand_int_range(0, N_TIMERS);
  71. if (is_disabled[idx])
  72. continue;
  73. is_disabled[idx] = 1;
  74. timer_disable(timers[idx]);
  75. --n_active_timers;
  76. }
  77. tor_libevent_run_event_loop(tor_libevent_get_base(), 0);
  78. int64_t total_difference = 0;
  79. uint64_t total_square_difference = 0;
  80. tor_assert(n_fired == n_active_timers);
  81. for (i = 0; i < N_TIMERS; ++i) {
  82. if (is_disabled[i]) {
  83. tor_assert(fired[i] == 0);
  84. continue;
  85. }
  86. tor_assert(fired[i] == 1);
  87. //int64_t diff = difference[i].tv_usec + difference[i].tv_sec * 1000000;
  88. int64_t diff = diffs_mono_usec[i];
  89. total_difference += diff;
  90. total_square_difference += diff*diff;
  91. }
  92. const int64_t mean_diff = total_difference / n_active_timers;
  93. printf("mean difference: "I64_FORMAT" usec\n",
  94. I64_PRINTF_ARG(mean_diff));
  95. const double mean_sq = ((double)total_square_difference)/ n_active_timers;
  96. const double sq_mean = mean_diff * mean_diff;
  97. const double stddev = sqrt(mean_sq - sq_mean);
  98. printf("standard deviation: %lf usec\n", stddev);
  99. #define MAX_DIFF_USEC (500*1000)
  100. #define MAX_STDDEV_USEC (500*1000)
  101. #define ODD_DIFF_USEC (2000)
  102. #define ODD_STDDEV_USEC (2000)
  103. if (mean_diff < 0 || mean_diff > MAX_DIFF_USEC || stddev > MAX_STDDEV_USEC) {
  104. printf("Either your system is under ridiculous load, or the "
  105. "timer backend is broken.\n");
  106. ret = 1;
  107. } else if (mean_diff > ODD_DIFF_USEC || stddev > ODD_STDDEV_USEC) {
  108. printf("Either your system is a bit slow or the "
  109. "timer backend is odd.\n");
  110. ret = 0;
  111. } else {
  112. printf("Looks good enough.\n");
  113. ret = 0;
  114. }
  115. timer_free_(NULL);
  116. for (i = 0; i < N_TIMERS; ++i) {
  117. timer_free(timers[i]);
  118. }
  119. timers_shutdown();
  120. return ret;
  121. }