休眠启动非常慢

由于某种原因，我的休眠应用程序的启动速度非常慢。（最多 2 分钟）我一直认为c3p0配置是完全错误的（相关问题），但研究日志表明，在与服务器的连接建立后没有任何活动。此外，使用Hibernate的内置轮询功能会显示相同的结果。

以下是日志中的一个片段：

20:06:51,248 DEBUG BasicResourcePool:422 - decremented pending_acquires: 0
20:06:51,248 DEBUG BasicResourcePool:1644 - trace com.mchange.v2.resourcepool.BasicResourcePool@1acaf0ed [managed: 3, unused: 2, excluded: 0] (e.g. com.mchange.v2.c3p0.impl.NewPooledConnection@5f873eb2)
20:06:51,248 DEBUG BasicResourcePool:1644 - trace com.mchange.v2.resourcepool.BasicResourcePool@1acaf0ed [managed: 3, unused: 2, excluded: 0] (e.g. com.mchange.v2.c3p0.impl.NewPooledConnection@5f873eb2)
20:06:51,273 DEBUG JdbcServicesImpl:121 - Database ->
       name : PostgreSQL
    version : 9.1.6
      major : 9
      minor : 1
20:06:51,274 DEBUG JdbcServicesImpl:127 - Driver ->
       name : PostgreSQL Native Driver
    version : PostgreSQL 9.2 JDBC4 (build 1002)
      major : 9
      minor : 2
20:06:51,274 DEBUG JdbcServicesImpl:133 - JDBC version : 4.0 ##### HANGS FOR 2 MINUTES  ON THIS LINE #####
20:08:14,727  INFO Dialect:123 - HHH000400: Using dialect: org.hibernate.dialect.PostgreSQLDialect
20:08:14,736  INFO LobCreatorBuilder:120 - HHH000424: Disabling contextual LOB creation as createClob() method threw error : java.lang.reflect.InvocationTargetException
20:08:14,736 DEBUG GooGooStatementCache:297 - checkinAll(): com.mchange.v2.c3p0.stmt.GlobalMaxOnlyStatementCache stats -- total size: 0; checked out: 0; num connections: 0; num keys: 0
20:08:14,736 DEBUG GooGooStatementCache:297 - checkinAll(): com.mchange.v2.c3p0.stmt.GlobalMaxOnlyStatementCache stats -- total size: 0; checked out: 0; num connections: 0; num keys: 0
20:08:14,883 DEBUG BasicResourcePool:1644 - trace com.mchange.v2.resourcepool.BasicResourcePool@1acaf0ed [managed: 3, unused: 2, excluded: 0] (e.g. com.mchange.v2.c3p0.impl.NewPooledConnection@5f873eb2)
20:08:14,883 DEBUG BasicResourcePool:1644 - trace com.mchange.v2.resourcepool.BasicResourcePool@1acaf0ed [managed: 3, unused: 2, excluded: 0] (e.g. com.mchange.v2.c3p0.impl.NewPooledConnection@5f873eb2)
20:08:14,883 DEBUG GooGooStatementCache:297 - checkinAll(): com.mchange.v2.c3p0.stmt.GlobalMaxOnlyStatementCache stats -- total size: 0; checked out: 0; num connections: 0; num keys: 0

（请注意 #comment#。

我还尝试了一个较旧的Postgres JDBC驱动程序，没有任何运气。

连接到本地数据库工作正常。立即建立连接，我可以查询数据库。此远程数据库是 Heroku 开发实例。我也用另一个遥控器尝试了它。同样的结果。

我不知道我现在可以检查什么来摆脱这种烦恼。任何帮助将不胜感激。

也许我的冬眠.cfg.xml很有帮助：

http://www.hibernate.org/dtd/hibernate-

configuration-3.0.dtd">
<hibernate-configuration>
    <session-factory>
        <property name="connection.driver_class">org.postgresql.Driver</property>
        <property name="connection.url"/>
        <property name="connection.default_schema"/>
        <property name="connection.username"/>
        <property name="connection.password"/> 

        <property name="dialect">org.hibernate.dialect.PostgreSQLDialect</property>
            <property name="cache.provider_class">org.hibernate.cache.internal.NoCacheProvider</property>
        <property name="current_session_context_class">thread</property>            
        <property name="hibernate.c3p0.acquire_increment">3</property>
        <property name="hibernate.c3p0.min_size">3</property>
        <property name="hibernate.c3p0.max_size">10</property>
        <property name="hibernate.c3p0.timeout">300</property>
        <property name="hibernate.c3p0.max_statements">50</property>
        <property name="hibernate.c3p0.idle_test_period">3000</property>
        <property name="hibernate.c3p0.acquireRetryDelay">500</property>

        <property name="show_sql">true</property>
        <property name="format_sql">false</property>

        <property name="hbm2ddl.auto">validate</property>

        <mapping class="core.entities.Exam" />
        <mapping class="core.entities.Examination" />
        ...
    </session-factory>
</hibernate-configuration>

编辑：我试图通过日志和分析找到延迟的原因，但一直没有成功。（不过，我在这方面并不先进。最后，我确实尝试并失败了，并更改了远程MySQL实例的数据库，以检查是否发生任何差异。事实证明，连接几乎是立即建立的。