Question

在我的应用程序中使用C3P0连接到DB服务器。这里DB服务器在防火墙后面运行。

防火墙有时行为不端，因为TCP连接变得半开，C3P0认为这些是有效的连接，并试图触发查询。 C3P0辅助线程正在进行这些半开放查询，应用程序线程正在挨饿。

`"com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#1" daemon prio=10 tid=0x00007fec0865d000 nid=0xc1fe runnable [0x00007fec4cb66000]
       java.lang.Thread.State: RUNNABLE
        at java.net.SocketInputStream.socketRead0(Native Method)
        at java.net.SocketInputStream.read(SocketInputStream.java:152)
        at java.net.SocketInputStream.read(SocketInputStream.java:122)
        at com.ingres.gcf.dam.IoBuff.fillBuffer(Unknown Source)
        at com.ingres.gcf.dam.IoBuff.next(Unknown Source)
        - locked <0x0000000782455468> (a com.ingres.gcf.dam.InBuff)
        at com.ingres.gcf.dam.InBuff.receive(Unknown Source)
        at com.ingres.gcf.dam.MsgIn.receive(Unknown Source)
        at com.ingres.gcf.dam.MsgConn.receive(Unknown Source)
        at com.ingres.gcf.jdbc.DrvObj.readResults(Unknown Source)
        at com.ingres.gcf.jdbc.JdbcConn.connect(Unknown Source)
        at com.ingres.gcf.jdbc.JdbcConn.<init>(Unknown Source)
        at com.ingres.gcf.jdbc.JdbcDrv.connect(Unknown Source)
        at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:81)
        - locked <0x0000000780025b10> (a com.mchange.v2.c3p0.DriverManagerDataSource)
        at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:96)
        - locked <0x0000000780025b70> (a com.mchange.v2.c3p0.WrapperConnectionPoolDataSource)
        at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1.acquireResource(C3P0PooledConnectionPool.java:89)
        at com.mchange.v2.resourcepool.BasicResourcePool.acquireUntil(BasicResourcePool.java:665)
        at com.mchange.v2.resourcepool.BasicResourcePool.access$500(BasicResourcePool.java:32)
        at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1206)
        at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:368)
    `

有没有可以解决这种情况的工作？

使用的数据库是VECTORWISE数据库。

Answer 1

如果套接字读取，从应用程序的角度来看，无限期挂起 - 既没有成功也没有失败Exception - c3p0唯一可以真正做到的就是把它们抽出来试图打断它们

您在上面显示的失败不在查询中，而是在Connection获取中。您可以尝试设置maxAdministrativeTaskTime来计算时间。显然，如果c3p0无法获取Connections，则尝试使用DataSource仍然会失败。但他们应该（最终，经过大量超时后，请acquireRetryAttempts和acquireRetryDelay）明确地与客户进行Exceptions，而不是仅仅等待

（这取决于挂起对Thread.interrupt()的敏感程度。如果它们无法中断，maxAdministrativeTaskTime无法帮助。）

C3P0半开连接关闭

1 个答案: