From the MySQL v6 manual:
When using transactional tables, Maria supports a single writer and
multiple readers. The single writer supports both
All issued SELECT's are running concurrently. While a SELECT is running,
all writers (INSERT, DELETE, UPDATE) are blocked from using any of the used
tables (ie, they wait for the table to be free before continuing).
If it does support a single writer and multiple readers, why are the
writers blocked when a Select is running? Shouldn't a single writer be able
to run with concurrent Selects?