Jepsen tested MariaDB Galera Cluster, versions 12.1.2 through 12.2.2, and found two scenarios which led to the loss of committed transactions. First, under the recommended configuration settings it does not flush data to disk before acknowledgement; committed transactions can be lost when nodes crash in quick succession. Second, it occasionally loses committed transactions with process crashes and network partitions. Even without faults, MariaDB Galera Cluster allows P4 (Lost Update), and therefore fails to satisfy its claimed isolation level “between Serializable and Repeatable Read”. It also regularly exhibits Stale Read.