使用Heroku Postgres的C3P0连接池停顿

Question

这与之前未解决的一个帖子有关：这里C3P0似乎在Heroku上初始化连接池后立即进入死锁。这个问题不会发生在我的本地邮件上。

 <property name="hibernate.dialect">org.hibernate.dialect.PostgreSQLDialect</property>



    <!-- Enable Hibernate's automatic session context management -->
    <property name="current_session_context_class">thread</property>


    <property name="hibernate.connection.url">jdbc:postgresql://myurl:5432/mydb?user=myusername&amp;password=myoassword&amp;sslfactory=org.postgresql.ssl.NonValidatingFactory&amp;ssl=true</property>
    <property name="hibernate.connection.driver_class">org.postgresql.Driver</property>
    <property name="hibernate.connection.username">myusername</property>
    <property name="hibernate.connection.password">mypassword</property>
    <property name="hibernate.archive.autodetection">class</property>
    <property name="hibernate.show_sql">true</property>
    <property name="hibernate.format_sql">true</property>
    <property name="hbm2ddl.auto">create</property>

    <!-- c3p0 connection pool settings -->
    <property name="hibernate.connection.provider_class">org.hibernate.service.jdbc.connections.internal.C3P0ConnectionProvider</property>
    <property name="hibernate.c3p0.min_size">1</property>
    <property name="hibernate.c3p0.max_size">2</property>
    <property name="hibernate.c3p0.timeout">1800</property>

[DEBUG]“com.mchange.v2.resourcepool.basicresourcepool”2015-07-05 07:12:59,132:成功终止获取系列。递减的pending_acquires 1,Attests_Retailing：30

[DEBUG]“com.mchange.v2.resourcepool.basicresourcepool”2015-07-05 07:12:59,132:跟踪com.mchange.v2.resourcepool.basicresourcepool@6293abcc[已管理：2,未使用：1,已排除：0]（例如com.mchange.v2.c3p0.impl.newpooledconnection@576ddf03)

[DEBUG]“com.mchange.v2.resourcepool.basicresourcepool”2015-07-05 07:12:59,132:递减的挂起_acquires：0

[DEBUG]“com.mchange.v2.resourcepool.basicresourcepool”2015-07-05 07:12:59,132:成功终止获取系列。递减的pending_acquires[0],Attests_Rething:30

[DEBUG]“com.mchange.v2.resourcepool.basicresourcepool”2015-07-05 07:12:59,132:跟踪com.mchange.v2.resourcepool.basicresourcepool@6293abcc[已管理：2,未使用：1,已排除：0]（例如com.mchange.v2.c3p0.impl.newpooledconnection@576ddf03)

[DEBUG]“com.mchange.v2.async.ThreadPoolAsynchronousRunner”2015-07-05 07:13:07,841:com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadLockDetector@45912FB9--正在运行DeadLockDetector[正在退出。没有挂起的任务。]

[DEBUG]“com.mchange.v2.async.ThreadPoolAsynchronousRunner”2015-07-05 07:13:55,576:com.mchange.v2.async.ThreadPoolAsynchronousRunner@6a01e23:将任务添加到队列--com.mchange.v2.resourcePool.basicResourcePool$1RevurbishCheckinResourceTask@55b699ef

Answer 1

答案其实已经贴出并在这里作了很好的解释：

我在hibernate.hbm.xml中添加了以下内容

<property name="temp.use_jdbc_metadata_defaults">false</property>