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From "Abdullah Kauchali" <abdullah.kauch...@isanusi.com>
Subject RE: What is RequestScope used for?
Date Tue, 06 Mar 2007 17:22:26 GMT
Notwithstanding the OP's issue .  is there any sensible way of preventing
this?  Ie. how to detect connections are being returned to the pool without
them properly ending transactions?


Is it even possible?




From: Clinton Begin [mailto:clinton.begin@gmail.com] 
Sent: Tuesday, March 06, 2007 6:40 PM
To: user-java@ibatis.apache.org
Subject: Re: What is RequestScope used for?


Yep, you have a leak and it is RequestScope related...but it's likely not an
ibatis bug...

It's more likely that you're not ending transactions properly.

try {
  ///... do work
} finally {


On 3/6/07, Kalcevich, Daniel < dkalcevich@firstam.com
<mailto:dkalcevich@firstam.com> > wrote:

OK, upon looking at the Yourkit, I am showing the number of objects in
memory as the following:


-          com.ibatis.sqlmap.engine.impl.SqlMapClientImpl - 212 objects with
a total retained size in memory of 31.38MB

-          com.ibatis.sqlmap.engine.scope.RequestScope - 108, 544 objects
with a total retained size in memory of 16.49MB.

-          com.ibatis.sqlmap.engine.scope.SessionScope - 27,136 objects with
a total retained size in memory of 3.03 MB.


Do those numbers make sense?  I only question it because with every snapshot
of the memory I have taken along the way, the RequestScope/SessionScope
objects keep increasing.





From: Kalcevich, Daniel 
Sent: Tuesday, March 06, 2007 7:04 AM
To: 'user-java@ibatis.apache.org'
Subject: RE: What is RequestScope used for?


I found about this RequestScope through the profiler YourKit.  Here is the
trail that references the IBatis objects.


map of com.ibatis.sqlmap.engine.scope.RequestScope 

--[121] of java.lang.Object[513] 

---elementData of java.util.ArrayList 

----list of java.util.Collections$SynchronizedRandomAccessList 

-----pool of com.ibatis.common.util.ThrottledPool 

------requestPool of com.ibatis.sqlmap.engine.impl.SqlMapExecutorDelega te 

------delegate of com.ibatis.sqlmap.engine.impl.SqlMapClientImpl 

-------client of com.ibatis.dao.engine.transaction.sqlmap.SqlMapDao

--------transactionManager of com.ibatis.dao.engine.impl.DaoContext 

---------[0] of java.lang.Object[11] 

----------elementData of java.util.ArrayList 

-----------value of java.lang.ThreadLocal$ThreadLocalMap$Entry 

------------[1442] of java.lang.ThreadLocal$ThreadLocalMap$Entry[2049] 

-------------table of java.lang.ThreadLocal$ThreadLocalMap 

--------------threadLocals of java.lang.Thread [Stack Local, Thread]



The reason I thought it might be contributing to a memory leak was the fact
that at every snapshot I take, the number of HashMaps continues to increase
without going down.  Then when I look at what it is referring to, it points
to the RequestScope.


While looking in the trace, I saw that it was referencing the DaoContext's
transaction Manager.  Could the Transaction Manager be playing a part in
this?  My application uses Spring with SQL Maps, but a library we wrote uses
the DAO Framework specifically.  The Spring application does not use it.  I
think that is worth looking into, given what I see in the profiler.






From: Kalcevich, Daniel 
Sent: Monday, March 05, 2007 11:37 AM
To: 'user-java@ibatis.apache.org'
Subject: What is RequestScope used for?




I have a Spring, Struts, SQL Map application that runs on JBoss/Tomcat.  And
while going through a profiler, I am seeing that there are several instances
of "com.ibatis.sqlmap.engine.scope.RequestScope".  What is that object used
for?  The reason I ask is that I am trying to track down a memory leak and
am wondering if this class is possibly part of the cause?  Any help is
greatly appreciated.  Thank you.




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