test/core/support/backoff_test.c

/*
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 * in the documentation and/or other materials provided with the
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#include "src/core/lib/support/backoff.h"

#include <grpc/support/log.h>

#include "test/core/util/test_config.h"

static void test_constant_backoff(void) {
  gpr_backoff backoff;
  gpr_backoff_init(&backoff, 1.0, 0.0, 1000, 1000);

  gpr_timespec now = gpr_time_0(GPR_TIMESPAN);
  gpr_timespec next = gpr_backoff_begin(&backoff, now);
  GPR_ASSERT(gpr_time_to_millis(gpr_time_sub(next, now)) == 1000);
  for (int i = 0; i < 10000; i++) {
    next = gpr_backoff_step(&backoff, now);
    GPR_ASSERT(gpr_time_to_millis(gpr_time_sub(next, now)) == 1000);
    now = next;
  }
}

static void test_no_jitter_backoff(void) {
  gpr_backoff backoff;
  gpr_backoff_init(&backoff, 2.0, 0.0, 1, 513);

  gpr_timespec now = gpr_time_0(GPR_TIMESPAN);
  gpr_timespec next = gpr_backoff_begin(&backoff, now);
  GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(1, GPR_TIMESPAN), next) == 0);
  now = next;
  next = gpr_backoff_step(&backoff, now);
  GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(3, GPR_TIMESPAN), next) == 0);
  now = next;
  next = gpr_backoff_step(&backoff, now);
  GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(7, GPR_TIMESPAN), next) == 0);
  now = next;
  next = gpr_backoff_step(&backoff, now);
  GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(15, GPR_TIMESPAN), next) == 0);
  now = next;
  next = gpr_backoff_step(&backoff, now);
  GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(31, GPR_TIMESPAN), next) == 0);
  now = next;
  next = gpr_backoff_step(&backoff, now);
  GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(63, GPR_TIMESPAN), next) == 0);
  now = next;
  next = gpr_backoff_step(&backoff, now);
  GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(127, GPR_TIMESPAN), next) == 0);
  now = next;
  next = gpr_backoff_step(&backoff, now);
  GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(255, GPR_TIMESPAN), next) == 0);
  now = next;
  next = gpr_backoff_step(&backoff, now);
  GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(511, GPR_TIMESPAN), next) == 0);
  now = next;
  next = gpr_backoff_step(&backoff, now);
  GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(1023, GPR_TIMESPAN), next) == 0);
  now = next;
  next = gpr_backoff_step(&backoff, now);
  GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(1536, GPR_TIMESPAN), next) == 0);
  now = next;
  next = gpr_backoff_step(&backoff, now);
  GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(2049, GPR_TIMESPAN), next) == 0);
  now = next;
  next = gpr_backoff_step(&backoff, now);
  GPR_ASSERT(gpr_time_cmp(gpr_time_from_millis(2562, GPR_TIMESPAN), next) == 0);
}

int main(int argc, char **argv) {
  grpc_test_init(argc, argv);
  gpr_time_init();

  test_constant_backoff();
  test_no_jitter_backoff();

  return 0;
}