Do people still use J2SE platforms? Of course. Does batch processing still happen? Does Legacy processing still happen even when people only want to do the new things. You betca.

We are running the HP HotSpot JVM 1.6. Cool in that with the HPJmeter (Free from HP) we can see inside the JVM and they did not have to do anything other than use Java 1.6. HPJmeter will see all the JVMs running Java 1.6 on that system. Using x-windows and the hpjmeter java app and a java connector that the install of HPJmeter starts up as root. That enables dynamic connections to the JVM to do the simple stuff.

This is not Wily or Dynatrace or other special products, but it is simple insight into what is happening. What are the threads that are started, what their stack is like, Heap sizes, (all of them). Lock contention is also seen.

The application team sent through some 5,000 MQ messages and we watched how it handled them. This is a very old applicaiton so they don’t want to spend much money on fixing it up. They set the MQ threads and DB threads along time ago. They follow the old standard, if it is not broken so that someone notices, don’t tell me about it. Or don’t expect me to fix it now. At one time they must have increased the number of MQ handles without knowing that the inside DB activity also needed to be adjusted. The increased MQ handles made the MQ Queue notices go away, so end of story. Now it uses more memory and waits inside the JVM where as before it waited outside the JVM.

If we need to come back to this module again, we will need to find a reason to also upgrade the INI fields to change a few other things. Until then – we are happy that at least it is not 100% in error recovery like it was the other week when it caused all the CPUs to be pegged at 100% and then caused major problems for everyone else.

Till next time.

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