presto-main/src/main/java/io/prestosql/transaction/InMemoryTransactionManager.java/InMemoryTransactionManager/scheduleIdleChecks
class InMemoryTransactionManager:    private void scheduleIdleChecks(Duration idleCheckInterval, ScheduledExecutorService idleCheckExecutor)
    {
        idleCheckExecutor.scheduleWithFixedDelay(() -> {
            try {
                cleanUpExpiredTransactions();
            }
            catch (Throwable t) {
                log.error(t, "Unexpected exception while cleaning up expired transactions");
            }
        }, idleCheckInterval.toMillis(), idleCheckInterval.toMillis(), MILLISECONDS);
    }