Status: On Hold
Affects Version/s: 5.7.28-31.41
Fix Version/s: None
A whole cluster gets effectively blocked for writes when a DDL query fails to successfully trigger brute force abort. And this is happening when
So, as a result, we can observe long waiting for MDL lock, which should never happen in PXC/Galera due to priority nature of DDL handling, like:
An example debug level log from affected node in attachment.
Use PXC node member with
In session one start a transaction on a simple table:
In session 2 on the same node, try a DDL on the same table, like:
Confirmed on PXC 5.7.26, .27 and .28.