presto-main/src/main/java/io/prestosql/execution/QueryStateTimer.java/QueryStateTimer/getElapsedTime
class QueryStateTimer:    public Duration getElapsedTime()
    {
        if (endNanos.get() != null) {
            return succinctNanos(endNanos.get() - createNanos);
        }
        return nanosSince(createNanos, tickerNanos());
    }