Re: Finding Broker/Connection leak

Tino Schöllhorn wrote:
> Dear Armin,
> 
> thanks for your reply. I will try to integrate the finalize()-code in 
> our PB.
> 
> Is there somewhere a document of the history of changes of OJB 1.0.1 to 
> the current released version? I'm asking because we are thinking of 
> moving to the current version and I want to estimate the impact to our 
> system.
>

Normally all changes are documented in the release-notes.
http://db.apache.org/ojb/release-notes.txt

There is only one fault in 1.0.4 release notes section. I forget to 
document a change in sequence/identity handling (if you force 
computation of unique values).
http://www.mail-archive.com/ojb-user%40db.apache.org/msg15405.html

To get an impression of the changes made for the upcoming version (OJB 
1.0.5, SVN OJB_1_0_RELEASE branch) have a look here
http://svn.apache.org/viewvc/db/ojb/branches/OJB_1_0_RELEASE/release-notes.txt?revision=421042&view=markup

regards
Armin


> With regards
> Tino
> 
> Armin Waibel wrote:
>> Hi Tino,
>>
>> Tino Schöllhorn wrote:
>>> Hi,
>>>
>>> I have a situation where we are running out of PersistenceBrokers 
>>> (using 1.0.1). We have a web application which so far runs fine - but 
>>> somehow some requests are causing the application not to close its PB.
>>>
>>> We can see this when we are monitoring the used connections of mysql 
>>> which are slowly growing - even if we are using ConnectionPooling. 
>>> These  connection are on the state SLEEP for quite a long time and 
>>> seem never to be closed.
>>>
>>> At some point the application runs out of PB (we are using size 100 
>>> of the PB-Pool).
>>>
>>> So it seems (quite obviously) that some PBs are not cleanly handled.
>>>
>>> Do you have any advice for us finding those leaks?
>>>
>>
>> In current versions there is no PB leak detection. Such a feature will
>> be part of the next version (or try latest from SVN OJB_1_0_RELEASE 
>> branch).
>> It would be possible to modify your 1.0.1 version to support broker 
>> leak detection. Have a look in latest PBImpl (OJB_1_0_RELEASE branch) 
>> and port the detection part in method PBimpl#setClosed and 
>> PBImpl#finalize to your class.
>> http://svn.apache.org/viewvc/db/ojb/branches/OJB_1_0_RELEASE/src/java/org/apache/ojb/broker/core/PersistenceBrokerImpl.java?revision=398752&view=markup 
>>
>>
>>
>>> Does it do any good when we "tune" mysql that it discards connections 
>>> which are quite old (via property "max_timeout")? Is OJB discaring 
>>> those PBs whose connections have died ?
>>
>> If you correctly use the PB instances (lookup PB instance when needed, 
>> close it after use) the connection pool should handle connections in a 
>> correct way.
>> But if you don't close PB instances after a query, the connection will 
>> still be associated with the PB instance, please see
>>
>> http://www.mail-archive.com/ojb-user%40db.apache.org/msg15389.html
>>
>> regards,
>> Armin
>>
>>>
>>> I am glad for any suggestions.
>>>
>>> Tino
>>>
>>>
>>> ---------------------------------------------------------------------
>>> To unsubscribe, e-mail: [email protected]
>>> For additional commands, e-mail: [email protected]
>>>
>>>
> 
> 
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: [email protected]
> For additional commands, e-mail: [email protected]
> 
>