public static long nanosToMillis(long nanos) {
    return nanos / NANOS_PER_MILLISECOND;
  }
Converts nanoseconds to milliseconds by dividing nanos by {@link #NANOS_PER_MILLISECOND}.

@param nanos value in nanoseconds
@return value converted to milliseconds
geode-core/src/main/java/org/apache/geode/internal/NanoTimer.java