c3p0 connection management problems

[eborix13]

Hi,

I'm using Spring 3.0.2, Hibernate 3.5.0 and c3p0 0.9.1.2 and I'm having a ton of errors when it comes down to retrieving connections and commiting transactions. Here's my configuration of c3p0:

<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close">
        <property name="driverClass" value="${jdbc.driverClassName}"/>
        <property name="jdbcUrl" value="${jdbc.url}"/>
        <property name="properties">
            <props>
                <prop key="c3p0.acquireIncrement">5</prop>
                <prop key="c3p0.maxIdleTime">30</prop>
                <prop key="c3p0.idleConnectionTestPeriod">20</prop>
                <prop key="c3p0.maxPoolSize">100</prop>
                <prop key="c3p0.maxStatements">0</prop>
                <prop key="c3p0.minPoolSize">1</prop>
                <prop key="user">${jdbc.username}</prop>
                <prop key="password">${jdbc.password}</prop>
            </props>
        </property>
    </bean>

Up until recently I got this error pretty often:

com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
Last packet sent to the server was 0 ms ago.

Recently I also get these:

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Connection.close() has already been called. Invalid operation in this state.
java.sql.SQLException: Connections could not be acquired from the underlying database!

Any suggestions?

[bhumir81]

<bean id="dataSource"
class="com.mchange.v2.c3p0.ComboPooledDataSource"
destroy-method="close">

<property name="driverClass"><value>${jdbc.driverClassName}</value></property>
<property name="jdbcUrl"><value>${jdbc.url}</value></property>
<property name="user"><value>${jdbc.username}</value></property>
<property name="password"><value>${jdbc.password}</value></property>

<property name="initialPoolSize"><value>3</value></property>
<property name="minPoolSize"><value>3</value></property>
<property name="maxPoolSize"><value>50</value></property>
<!-- <property name="timeout"><value>0</value></property> --> <!-- 0 means: no timeout -->
<property name="idleConnectionTestPeriod"><value>200</value></property>
<property name="acquireIncrement"><value>1</value></property>
<property name="maxStatements"><value>0</value></property> <!-- 0 means: statement caching is turned off. -->
<property name="numHelperThreads"><value>3</value></property> <!-- 3 is default -->

</bean>