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<a href="http://community.jboss.org/index.jspa" style="text-decoration: none; color: #E1E1E1">Community</a></h1>
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How can you turn of EJB 3 invocation statistics
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reply from <a href="http://community.jboss.org/people/andy.miller%40jboss.com">Andrig Miller</a> in <i>EJB 3.0</i> - <a href="http://community.jboss.org/message/544086#544086">View the full discussion</a>
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<div class="jive-rendered-content"><blockquote class="jive-quote"><p>Carlo de Wolf wrote:</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>First I want to see some measurements to know the extend of the problem and to have a base of comparison.</p></blockquote><p>Well, I did measurements.  I ran a test with 5 stateless session beans that did nothing but call each other and return.  I did this on a 8 core system with Hyperthreading (16 virtual cores), at 600 users with no think times.  Just hammer the server.</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>In that test, I could only measure an average of 1.33% difference between running with the statistics, and running with a patched server with all statistics completely removed from the container.</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>After going through the trouble to remove the statistics competely from the container, the results make sense to me know.  The reason I thought this might be an issue is a customer had e-mailed me saying he thought it was a bottleneck.  I need to get back to him, and see why he thinks that is true, and what he is seeing.  My tests simply don't back that up.  In the code, we are already using volatiles for all the counters, and a ConcurrentReaderHashMap to store the instances of the InvocationStatistics object (which makes complete sense in that you only create the instance once and store it once, and the rest of the time is spend getting from the HashMap).  The only synchronization, that seemed problematic, is in the "concurrent calls" code (callIn, callOut methods), but my test proves its not a real issue.</p><p style="min-height: 8pt; height: 8pt; padding: 0px;"> </p><p>So, I'll turn my attention elsewhere.</p></div>
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<p style="margin: 0;">Reply to this message by <a href="http://community.jboss.org/message/544086#544086">going to Community</a></p>
<p style="margin: 0;">Start a new discussion in EJB 3.0 at <a href="http://community.jboss.org/choose-container!input.jspa?contentType=1&containerType=14&container=2029">Community</a></p>
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