Delete failed, several errors

Hi, I installed MariaDB ColumnStore 1.0.8. I use 1 PM and the storage is internal. I'm dealing with bulk data. For instance, 'test_log' table has 100,000,000 rows.

It succeeded to delete 100,000 rows.

MariaDB [input_test]> delete from test_log where stime < '2017-03-31 00:00:00' limit 100000;
Query OK, 100000 rows affected (9.67 sec)

However, when I tried deleting 1,000,000 rows from test_log table, it shows an error as follows:

MariaDB [input_test]> delete from test_log where stime < '2017-03-31 00:00:00' limit 1000000;
ERROR 1815 (HY000): Internal error: ClientRotator caught exception: InetStreamSocket::write error: Broken pipe -- write from InetStreamSocket: sd: 19 inet: 127.0.0.1 port: 8601

I performed the same query again, it succeeded!

MariaDB [input_test]> delete from test_log where stime < '2017-03-31 00:00:00' limit 1000000;
Query OK, 1000000 rows affected (1 min 28.25 sec)

Once I deleted 10,000,000 rows, another error occurred.

MariaDB [input_test]> delete from test_log where stime < '2017-03-31 00:00:00' limit 10000000;
ERROR 2013 (HY000): Lost connection to MySQL server during query

After the error occurred, I couldn't perform other queries with the table because it's locked.

MariaDB [input_test]> delete from test_log where stime < '2017-03-31 00:00:00' limit 10000000;
ERROR 1815 (HY000): Internal error: IDB-2009: Unable to perform the delete operation because DMLProc with PID 21714 is currently holding the table lock for session 2.

MariaDB [input_test]> truncate table test_log;
ERROR 1815 (HY000): Internal error: CAL0009: Truncate table failed:  IDB-2009: Unable to perform the DMLProc operation because 21714 with PID 2 is currently holding the table lock for session .

Could you let me know what the problem is? Why do these errors occur? And how can I fix it?

Thank you.