src/share/vm/gc/shared/genCollectedHeap.cpp

*** 1254,1278 ****
      _time = MIN2(_time, gen->time_of_last_gc(_now));
    }
  };
  
  jlong GenCollectedHeap::millis_since_last_gc() {
!   // We need a monotonically non-decreasing time in ms but
!   // os::javaTimeMillis() does not guarantee monotonicity.
    jlong now = os::javaTimeNanos() / NANOSECS_PER_MILLISEC;
    GenTimeOfLastGCClosure tolgc_cl(now);
    // iterate over generations getting the oldest
    // time that a generation was collected
    generation_iterate(&tolgc_cl, false);
  
-   // javaTimeNanos() is guaranteed to be monotonically non-decreasing
-   // provided the underlying platform provides such a time source
-   // (and it is bug free). So we still have to guard against getting
-   // back a time later than 'now'.
    jlong retVal = now - tolgc_cl.time();
    if (retVal < 0) {
!     NOT_PRODUCT(log_warning(gc)("time warp: " JLONG_FORMAT, retVal);)
      return 0;
    }
    return retVal;
  }
  
--- 1254,1277 ----
      _time = MIN2(_time, gen->time_of_last_gc(_now));
    }
  };
  
  jlong GenCollectedHeap::millis_since_last_gc() {
!   // javaTimeNanos() is guaranteed to be monotonically non-decreasing
!   // provided the underlying platform provides such a time source
!   // (and it is bug free). So we still have to guard against getting
!   // back a time later than 'now'.
    jlong now = os::javaTimeNanos() / NANOSECS_PER_MILLISEC;
    GenTimeOfLastGCClosure tolgc_cl(now);
    // iterate over generations getting the oldest
    // time that a generation was collected
    generation_iterate(&tolgc_cl, false);
  
    jlong retVal = now - tolgc_cl.time();
    if (retVal < 0) {
!     log_warning(gc)("millis_since_last_gc() would return : " JLONG_FORMAT
!        ". returning zero instead.", retVal);
      return 0;
    }
    return retVal;
  }