v8::base::anonymous_namespace{time-unittest.cc} Namespace Reference

Functions
template<typename T >
static void	ResolutionTest (T(*Now)(), TimeDelta target_granularity)

Function Documentation

ResolutionTest()

template<typename T >

static void v8::base::anonymous_namespace{time-unittest.cc}::ResolutionTest ( T(*)()  Now, TimeDelta  target_granularity  )

static

Definition at line 116 of file time-unittest.cc.

                                                                     {
  // We're trying to measure that intervals increment in a VERY small amount
  // of time -- according to the specified target granularity. Unfortunately,
  // if we happen to have a context switch in the middle of our test, the
  // context switch could easily exceed our limit. So, we iterate on this
  // several times. As long as we're able to detect the fine-granularity
  // timers at least once, then the test has succeeded.
  static const TimeDelta kExpirationTimeout = TimeDelta::FromSeconds(1);
  ElapsedTimer timer;
  timer.Start();
  TimeDelta delta;
  do {
    T start = Now();
    T now = start;
    // Loop until we can detect that the clock has changed. Non-HighRes timers
    // will increment in chunks, i.e. 15ms. By spinning until we see a clock
    // change, we detect the minimum time between measurements.
    do {
      now = Now();
      delta = now - start;
    } while (now <= start);
    EXPECT_NE(static_cast<int64_t>(0), delta.InMicroseconds());
  } while (delta > target_granularity && !timer.HasExpired(kExpirationTimeout));
  EXPECT_LE(delta, target_granularity);
}

References T.