ADVERTÊNCIA: Name = GaiaDataBase Property maxActive is not used in DBCP2, use maxTotal instead. maxTotal default value is 8. You have set value of "40" for "maxActive" property, which is being ignored.

<Resource auth="Container" driverClassName="org.postgresql.Driver" maxActive="40" name="jdbc/GaiaDataBase" password="blablabla" type="javax.sql.DataSource" url="jdbc:postgresql://192.168.1.78/MeuBanco" username="user_desenv"/>