Andrus,

Correct I did not have access to the JVM on the production server.  Even if I 
did, I could not predict when it was going to happen.  In addition, it *never* 
occurred on the development server.

The choices were not terribly satisfying: either work through the problem and 
determine an explicit cause (which could take many hours of work), or do as 
some middleware-developers suggest and replace your major components with the 
newest stable versions (i.e. eliminate scores of bugs) and 'get back to us if 
you still have a problem'. :)

Thanks again,
Joe



On Jun 23, 2010, at 2:06 AM, Andrus Adamchik wrote:

> Glad you figured it out. Tough to diagnose your apps when you don't even have 
> access to the JVM to check the state of the threads...
> 
> Andrus
> 
> On Jun 22, 2010, at 10:17 PM, Joe Baldwin wrote:
> 
>> RE Previous Excessive Load Times (60+ secs) /so-called  "Cayenne Connection 
>> Pool Errors" /so-called "Memory Management Errors" / etc
>> 
>> I wanted to thank everyone for commenting on the array of problems that is 
>> summarized above.  This is my feedback and what I believe to be the cause of 
>> the problem(s).
>> 
>> A few months ago, I had noticed a recurring and intermittent problem that 
>> showed itself as extremely long load times (sometimes 1-2 mins) even under 
>> very light load.  After reading through the log files and following 
>> suggestions from this forum, there was little change in the problem.  Since 
>> the webapp was hosted on a production server by commercial company, I had to 
>> work closely with the tech support guy who was first convinced that it was a 
>> problem in my ISP, then he was convinced it was Cayenne, then he was 
>> convinced that it was my code, and so on ...
>> 
>> However, this problem never once manifested itself on our development server 
>> under any kind of load.  So I doubted his analysis.
>> 
>> After a long process of testing and elimination, and following increasingly 
>> eccentric suggestions by the webhost tech guy, we fired the webhost and 
>> moved all of our code to a new webhost who had installed the newest stable 
>> versions of Java, Tomcat, and MySQL (something the previous webhost refused 
>> to do).
>> 
>> As a result, we have not experienced the load-time problem or Connection 
>> Pool errors since we changed webhosts.  We are using the same code, the same 
>> Cayenne configuration and version, and the same connector.   It looks like 
>> it was either some configuration parameters the webhost tech guy had 
>> overlooked or it was the 3 year old version of MySQL that they were running 
>> (that I found has documented table locking bugs).
>> 
>> Anyway thanks for helping out, this was a difficult problem to crack.
>> 
>> Joe
>> 
>> 
> 

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