Users timing out in Oracle AS 10.1.3

Question

I am trying to figure out why the load tests running in the target environment (large and very secure corporate network) against a Spring MVC/EJB3 application running in Orcale AS 10.1.3 fail. The application is deployed on a server running on a Solaris Sparc 440 machine.
The tests are run from LoadRunner application, which simulates multiple users sending HTTP requests to perform a use case in the system under test. The use case involves transitioning between 4 different pages with the application sending a number (relatively small, 5-6 pr use case) of queries to the Oracle database running on a different machine (using JPA/TopLink) and doing a single insert.
The LoadRunner shows that after a few minutes after the test starts the users start timing out. The HTTP request sent to the application server (with timeout value of two minutes) do not get fulfilled.
I have looked at various performance metrics: CPU and memory utilization on the Solaris machine, metrics provided by the Oracle AS admin console (JVM Heap memory usage, number of EJB methods per second, number of servlet requests per second and request processing time. Nothing indicates a bottleneck. The application uses much less memory than is allocated (100MB out of 2GB allowed), the CPU and memory utilization on the machine are within norm. The EJB methods execute in a fraction of a second (nothing to justify a two-minute delay).
An interesting aspect of the test is the effect of the static resources on the performance. About two thirds of HTTP request in the test are for static resources (GIFs and CSS). They are not being cached by the HTTP server. Two similar LoadRunner tests were performed. In one, all HTTP requests were submitted (20 users running 10 iterations each). In the second, LoadRunner itself cached the static resources, thus submitting only the requests processed by Spring MVC portion of the Java application (the same number of users and iterations). The second tests produced a much lower timeout rate. (Out of 218 transactions, 34 timed out in the first test and 2 in the second).
I am trying to understand what may cause the timeouts in these tests. The most obvious culprit is the Java application being tested, but if the bottleneck was in Java, then caching static resources would have almost no effect on the performance results (since static resources do not go to the Java application).
I tested the same application using Apache JMeter in the development environment (a small company network) with Oracle AS running on Solaris VM (itself running on a Windows machine, which is less powerful than the Sparc 440 machine). The test running exactly the same use case with 20 users running 200 iterations each went without a single hiccup. Not a single HTTP request timed out and the mean request time was 69 ms.
I am looking for help in finding the causes for the performance issues in the target environment and why they cannot be replicated in the development environment. What may be causing the simulated users to time out?
Thank you,
Michael

Answer 1

Yes OHS (Oracle HTTP Server) comes with PHP pre-installed and ready to use. Refer following for details:
http://download.oracle.com/docs/cd/B32110_01/web.1013/b28948/php.htm#BABIGCFB
Thanks
Shail