HI Clinton:
Have upgraded, and am refactoring some of my iBATIS code. You write:
"Pools handle closing connections, but you still have to call .close (or
some higher level delegating method) to return the connection to the
pool. The rules are always the same... if you open it / start it /
retrieve it, then you must close it / stop it / return it... "
Below is an example Dao method implementation - my understanding (wrong,
it would appear) is that the SqlMapClientDaoSupport takes care of
ope/start/retrieve and close/stop/return.
Do I need to enclose my call to getSqlMapClientTemplate().update(...) in
a try/catch with open/close?
Thanks again - looks like homing in on the issue.
Cheers,
parki...
--- x8 snip
public class AlertDao extends SqlMapClientDaoSupport implements
IAlertDao
{
public Acknowledgement acknowledgeAlert(String thermostatIdentifier,
String acknowledgeRef,
boolean remindMeLater) throws Exception
{
AlertEntry alertEntry = new AlertEntry(thermostatIdentifier,
acknowledgeRef);
getSqlMapClientTemplate().update("AlertMessage.updateByAlertEntry",
alertEntry);
Acknowledgement acknowledgedSet = new Acknowledgement();
acknowledgedSet.setThermostatIdentifier(thermostatIdentifier);
acknowledgedSet.setAcknowledgeRef(acknowledgeRef);
acknowledgedSet.setRemindMeLater(remindMeLater);
return acknowledgedSet;
}
________________________________
From: Clinton Begin [mailto:[EMAIL PROTECTED]
Sent: Wednesday, August 06, 2008 9:52 AM
To: [email protected]
Subject: Re: Thread starvation - pool / Throttle issue?
Pools handle closing connections, but you still have to call .close (or
some higher level delegating method) to return the connection to the
pool. The rules are always the same... if you open it / start it /
retrieve it, then you must close it / stop it / return it...
That said, upgrade to 2.3.3. Then you'll more easily find the true root
cause of your issue, as all of the Throttles have been removed for this
very reason. You'll likely get a complaint about no more connections,
or a DB deadlock.
Clinton
On Wed, Aug 6, 2008 at 7:18 AM, Brian Parkinson <[EMAIL PROTECTED]>
wrote:
HI Nicholoz - looked at that thread - thx.
A key issue seems to be not closing connections, but my
understanding is that the DBCP connection pool handles all that for me
(?).
The Dao implementation is pretty simple - I'm not explicitly
declaring transations, since using Spring transaction stuff and so each
Dao method looks like below.
Should I be explicitly handling transations stuff, and placing
everything inside try/catch/finally blocks? My understaniding was that
the Spring SqlMapClientDaoSupport did that for me.
public class AlertDao extends SqlMapClientDaoSupport implements
IAlertDao
{
public Acknowledgement acknowledgeAlert(String
thermostatIdentifier, String acknowledgeRef,
boolean remindMeLater) throws Exception
{
AlertEntry alertEntry = new AlertEntry(thermostatIdentifier,
acknowledgeRef);
getSqlMapClientTemplate().update("AlertMessage.updateByAlertEntry",
alertEntry);
Acknowledgement acknowledgedSet = new Acknowledgement();
acknowledgedSet.setThermostatIdentifier(thermostatIdentifier);
acknowledgedSet.setAcknowledgeRef(acknowledgeRef);
acknowledgedSet.setRemindMeLater(remindMeLater);
return acknowledgedSet;
}
... ETC ...
}
The Spring declaration:
<bean id="txManager"
class="org.springframework.jdbc.datasource.DataSourceTransactionManager"
>
<property name="dataSource" ref="dataSource"/>
</bean>
<tx:advice id="txAdvice" transaction-manager="txManager">
<tx:attributes>
<tx:method name="get*" read-only="true" />
<tx:method name="*" />
</tx:attributes>
</tx:advice>
<aop:config>
<aop:pointcut id="daoServiceOperation" expression="execution(*
com.ecobee.foundation.dao.ibatis.*.*(..))" />
<aop:advisor advice-ref="txAdvice"
pointcut-ref="daoServiceOperation" />
</aop:config>
Appreciated - regards -
parki...
________________________________
From: Nicholoz Koka Kiknadze [mailto:[EMAIL PROTECTED]
Sent: Wednesday, August 06, 2008 8:56 AM
To: [email protected]
Subject: Re: Thread starvation - pool / Throttle issue?
Have a look at this thread:
http://www.mail-archive.com/[email protected]/msg11828.html
Good luck
On Wed, Aug 6, 2008 at 4:47 PM, Brian Parkinson
<[EMAIL PROTECTED]> wrote:
Hello:
So, I have things up and running under Java and iBATIS,
but running into
some starvation issue, and my server is locking up. When
I dump threads,
I see a bunch that are waiting for the connnection pool
(see output #1
below) and as well, a bunch that are waiting on
Throttle.increment (see
output #2).
Has anyone see anything similar?
I am stumped right now - looking for ANY hints to help
me track down
(and fix :) what is going on - I don't know databases
all that well, so
help appreciated greatly. First up, I'm going to upgrade
to latest
version of iBATIS, but thinking I might have something
wrong in my
thread pool setup.
The pool setup:
<bean id="mapConfig"
class="org.springframework.core.io.ClassPathResource">
<constructor-arg>
<value>com/ecobee/foundation/dao/ibatis/SqlMapConfig.xml</value>
</constructor-arg>
</bean>
<bean id="dataSource"
class="org.apache.commons.dbcp.BasicDataSource"
destroy-method="close">
<property name="driverClassName"
value="com.mysql.jdbc.Driver" />
<property name="url"
value="jdbc:mysql:///ecobee" />
<property name="username" value="XXX" />
<property name="password" value="XXX" />
<property name="initialSize" value="10"
/>
<property name="maxActive" value="100" />
<property name="maxIdle" value="10" />
</bean>
<bean id="sqlMapClient"
class="org.springframework.orm.ibatis.SqlMapClientFactoryBean">
<property name="dataSource"
ref="dataSource" />
<property name="configLocation"
ref="mapConfig" />
</bean>
I currently have no <settings> element in my
SqlMapConfig.xml file, so
running with those defaults.
Any help is greatly appreciated - I am mystified.
I am using iBATIS 2.3.0.667 and commons dbcp 1.2.2, and
running MySQL
5.0.32.
Off to upgrade to latest iBATIS as a start -
Cheers,
parki...
--- x8 snip
Output #1:
Thread: Thread[pool-1-thread-121,5,main]=
-- java.lang.Object.wait(Native Method)
-- java.lang.Object.wait(Object.java:474)
--
org.apache.commons.pool.impl.GenericObjectPool.borrowObject(GenericObjec
tPool.java:810)
--
org.apache.commons.dbcp.PoolingDataSource.getConnection(PoolingDataSourc
e.java:96)
--
org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.ja
va:880)
--
org.springframework.jdbc.datasource.DataSourceTransactionManager.doBegin
(DataSourceTransactionManager.java:200)
--
org.springframework.transaction.support.AbstractPlatformTransactionManag
er.getTransaction(AbstractPlatformTransactionManager.java:377)
--
org.springframework.transaction.interceptor.TransactionAspectSupport.cre
ateTransactionIfNecessary(TransactionAspectSupport.java:261)
--
org.springframework.transaction.interceptor.TransactionInterceptor.invok
e(TransactionInterceptor.java:101)
--
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(Ref
lectiveMethodInvocation.java:171)
--
org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(E
xposeInvocationInterceptor.java:89)
--
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(Ref
lectiveMethodInvocation.java:171)
--
org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAo
pProxy.java:204)
-- $Proxy2.saveLogSet(Unknown Source)
--
com.ecobee.communicator.rest.restlet.LogRestlet.doPost(LogRestlet.java:7
6)
--
com.ecobee.communicator.rest.RestletManager.handleRequest(RestletManager
.java:195)
--
com.ecobee.communicator.engine.EngineRequest.handleRequest(EngineRequest
.java:112)
--
sun.reflect.GeneratedMethodAccessor338.invoke(Unknown Source)
--
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessor
Impl.java:25)
-- java.lang.reflect.Method.invoke(Method.java:585)
--
com.whatevernot.engine.standard.StateRunnable.run(StateRunnable.java:56)
--
java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecuto
r.java:650)
--
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.ja
va:675)
-- java.lang.Thread.run(Thread.java:595)
Output #2:
Thread: Thread[pool-1-thread-613,5,main]=
-- java.lang.Object.wait(Native Method)
-- java.lang.Object.wait(Object.java:474)
--
com.ibatis.common.util.Throttle.increment(Throttle.java:70)
--
com.ibatis.common.util.ThrottledPool.pop(ThrottledPool.java:57)
--
com.ibatis.sqlmap.engine.impl.SqlMapExecutorDelegate.popSession(SqlMapEx
ecutorDelegate.java:933)
--
com.ibatis.sqlmap.engine.impl.SqlMapSessionImpl.<init>(SqlMapSessionImpl
.java:51)
--
com.ibatis.sqlmap.engine.impl.SqlMapClientImpl.getLocalSqlMapSession(Sql
MapClientImpl.java:259)
--
com.ibatis.sqlmap.engine.impl.SqlMapClientImpl.startBatch(SqlMapClientIm
pl.java:161)
--
com.ecobee.foundation.dao.ibatis.LogDao.saveLogSet(LogDao.java:22)
--
sun.reflect.GeneratedMethodAccessor341.invoke(Unknown Source)
--
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessor
Impl.java:25)
-- java.lang.reflect.Method.invoke(Method.java:585)
--
org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(
AopUtils.java:301)
--
org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinp
oint(ReflectiveMethodInvocation.java:182)
--
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(Ref
lectiveMethodInvocation.java:149)
--
org.springframework.transaction.interceptor.TransactionInterceptor.invok
e(TransactionInterceptor.java:106)
--
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(Ref
lectiveMethodInvocation.java:171)
--
org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(E
xposeInvocationInterceptor.java:89)
--
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(Ref
lectiveMethodInvocation.java:171)
--
org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAo
pProxy.java:204)
-- $Proxy2.saveLogSet(Unknown Source)
--
com.ecobee.communicator.rest.restlet.LogRestlet.doPost(LogRestlet.java:7
6)
--
com.ecobee.communicator.rest.RestletManager.handleRequest(RestletManager
.java:195)
--
com.ecobee.communicator.engine.EngineRequest.handleRequest(EngineRequest
.java:112)
--
sun.reflect.GeneratedMethodAccessor338.invoke(Unknown Source)
--
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessor
Impl.java:25)
-- java.lang.reflect.Method.invoke(Method.java:585)
--
com.whatevernot.engine.standard.StateRunnable.run(StateRunnable.java:56)
--
java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecuto
r.java:650)
--
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.ja
va:675)
-- java.lang.Thread.run(Thread.java:595)
