presto-raptor-legacy/src/main/java/io/prestosql/plugin/raptor/legacy/storage/BucketBalancer.java/BucketBalancer/runBalanceJob
class BucketBalancer:    private void runBalanceJob()
    {
        try {
            balance();
        }
        catch (Throwable t) {
            log.error(t, "Error balancing buckets");
            jobErrors.update(1);
        }
    }