We're just upgrading from 5.7 to 5.12 and received the same warning. In our case Hive metastore heap size is 12G so the  max message size will be set to 1.2 G . That appears bit scary to me. What are the risks of setting the value such high ?  How can we handle large metastore updates in case that happens ? Do we need to prepare the metastore server i.e. mysql to do somethign differently ? What happens if we don't follow this recommandation ?   Thanks, Sunil ... View more