* Problem is here is CTAS is actually a DDL (cum DML) command that is executed using DML flow.
* Conflicting DDL can cause deadlock as explained above.
As galera protocol goes DDL are serialized so you can't replicate DDL concurrently.
-----------------
With that background and given the problem in PXC-5.7 we have disabled CTAS
but still left it out in 5.6 if user is operating CTAS in controlled fashion.
(to avoid immediate workload incompatibility on upgrade).
-----------------
If you are still hitting this problem then only solution I see is to avoid use of CTAS.
* Problem is here is CTAS is actually a DDL (cum DML) command that is executed using DML flow.
* Conflicting DDL can cause deadlock as explained above.
As galera protocol goes DDL are serialized so you can't replicate DDL concurrently.
-----------------
With that background and given the problem in PXC-5.7 we have disabled CTAS
but still left it out in 5.6 if user is operating CTAS in controlled fashion.
(to avoid immediate workload incompatibility on upgrade).
-----------------
If you are still hitting this problem then only solution I see is to avoid use of CTAS.