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Re: Failed to acquire the pool semaphore in empty pool
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created by <a href="http://community.jboss.org/people/garrydias">Garry Dias</a> in <i>EJB3</i> - <a href="http://community.jboss.org/message/625559#625559">View the full discussion</a>
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<div class="jive-rendered-content"><p>Let me explain better...</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>It´s my stateless bean:</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><pre class="jive-pre"><code class="jive-code">
@Clustered
@Stateless(name = "MyWorkerBean")
@Pool(value = PoolDefaults.POOL_IMPLEMENTATION_STRICTMAX, maxSize = 30)
public class MyWorkerBean implements WorkerInterface {
     public void sleep(boolean flag) throws Exception
     {
          Thread.sleep(60000);
     }
}
</code></pre><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>To stress this bean, I´m using a JMeter test case with 100 concurrent threads. Each thread perform a ejb lookUp for MyWorkerBean.</p><p>Each instance looked up performs a call to sleep() method. So, the first 30 lookups will perform and 70 will "Fail to aquire pool semaphore, strictTimeout=-1". </p><p>Now, I have 30 bean instances filling the pool for 60 seconds and the MBean for MyWorkerBean in jmx-console marks AvailableCount as 30.</p><p>After 60 seconds all 30 instances perform succesfully and I run 100 more jmeter threads, but this time all lookups blows with "Fail to aquire pool semaphore, strictTimeout=-1" and the MBean for MyWorkerBean in jmx-console marks AvailableCount as 0.</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>PS: the look up is performed by:</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><pre class="jive-pre"><code class="jive-code">org.springframework.beans.factory.BeanFactory.getBean("MyWorkerBean")</code></pre><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><h5><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p></h5><p><span></span></p></div>
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