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https://issues.apache.org/jira/browse/IBATIS-449?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12587977#action_12587977
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Gerhard Kersten commented on IBATIS-449:
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For us it's the same, and it's really mission-critical.

Background: A firewall cuts a TCP connection after some time, but does not 
close it. With "Ping enabled" iBatis waits forever (actually 943 s) for the 
ping. Wihout "Ping enabled" a SQLException is thrown (Time out in rollback), 
also not earlier than after some 900 s. Setting 
"sun.net.client.defaultReadTimeout=60000" does not help. Here an example with a 
simulated TCP delay of 600s (against sun.net.client.defaultReadTimeout=60s):
[EMAIL PROTECTED]:42:03 DEBUG     - Testing connection 27114948...
[EMAIL PROTECTED]:52:03 DEBUG     - Connection 27114948 is GOOD!

Setting maximumIdleConnections=0 as last hope is no option either, as it slows 
down everything significantly.

For Bea Datasources I have observed the same firewall problem, but there the 
ping request returns almost immerdiatly, even for a corrupted TCP connection. 
Maybe some solution with a separate watchguard thread?


> Is there a way to specify a timeout for Pool.PingQuery when using a jdbc 
> SimpleDataSource?
> ------------------------------------------------------------------------------------------
>
>                 Key: IBATIS-449
>                 URL: https://issues.apache.org/jira/browse/IBATIS-449
>             Project: iBatis for Java
>          Issue Type: Improvement
>         Environment: Red Hat Enterprise Linux 4 Update 5 x86-64, JBOSS 4.0.5
>            Reporter: Anton Rothenbacher
>            Priority: Critical
>
> It seems there is no way to specify a timeout when implementing the 
> Pool.PingQuery to test pooled connections before use. We are in an 
> environment that is closing connections on us and when the app is inactive 
> for a long time, the first connection to be tested out of the pool is bad, 
> and it takes 15 minutes before the connection is deemed bad and the 
> connection recycled.
> 2007-08-11 06:38:14,032 DEBUG [com.ibatis.common.jdbc.SimpleDataSource] 
> Checked out connection 2865240 from pool.
> 2007-08-11 06:38:14,032 DEBUG [com.ibatis.common.jdbc.SimpleDataSource] 
> Testing connection 2865240 ...
> .....
> 2007-08-11 06:53:40,695 WARN  [com.ibatis.common.jdbc.SimpleDataSource] 
> Execution of ping query 'select 1 from DUAL' failed: Io exception: Connection 
> timed out
> 2007-08-11 06:53:40,695 DEBUG [com.ibatis.common.jdbc.SimpleDataSource] 
> Connection 2865240 is BAD: Io exception: Connection timed out
> 2007-08-11 06:53:40,696 DEBUG [com.ibatis.common.jdbc.SimpleDataSource] A bad 
> connection (2865240) was returned from the pool, getting another connection.
> 2007-08-11 06:53:40,750 DEBUG [com.ibatis.common.jdbc.SimpleDataSource] 
> Created connection 10545003.
> This is a problem since the app hangs for the time when it is waiting for the 
> connection. We are looking for a way to speed up the PingQuery test so that 
> if it does not respond in x seconds, (it is a very fast query) then recycle 
> the connection right away, not 15min later when the connection times out.
> Here is the relevent section from our SqlMapConfig.xml
>     <!-- Configure a datasource to use with this SQL Map using 
> SimpleDataSource.
>     Notice the use of the properties from the above resource -->
>     <transactionManager type="JDBC" commitRequired="true">
>         <dataSource type="SIMPLE">
>             <property name="JDBC.Driver" value="${driver}"/>
>             <property name="JDBC.ConnectionURL" value="${url}"/>
>             <property name="JDBC.Username" value="${username}"/>
>             <property name="JDBC.Password" value="${password}"/>
>             <property name="JDBC.DefaultAutoCommit" 
> value="${jdbc.default.auto.commit}" />
>             <property name="Pool.MaximumActiveConnections" 
> value="${pool.maximum.active.connections}"/>
>             <property name="Pool.MaximumIdleConnections" 
> value="${pool.maximum.idle.connections}"/>
>             <property name="Pool.MaximumCheckoutTime" 
> value="${pool.maximum.checkout.time}"/>
>             <property name="Pool.TimeToWait" value="${pool.time.to.wait}"/>
>             <property name="Pool.PingQuery" value="select 1 from DUAL"/>
>             <property name="Pool.PingEnabled" value="true"/>
>             <property name="Pool.PingConnectionsOlderThan" value="1"/>
>             <property name="Pool.PingConnectionsNotUsedFor" value="1"/>
>         </dataSource>
>     </transactionManager>
> Is DBCP type connection better for what we wish to accomplish? It seems it 
> can test connections idle connections out of the pool on a regular basis but 
> as far as I can tell SimpleDataSource can only test connections as they are 
> requested out of the pool. Am I correct, does anyone have any suggestions?
> Thanks much for your time!

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