Re: Finding Broker/Connection leak

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.

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]
>>
>>