I have created a web application with struts 1.3.5 It is deployed on Tomcat 5.5.25 I am presently running stress tests and I am seeing a pretty weird behavior, it goes like this...
I start the test, and response times are acceptable, around 300 ms in average. What is strange is that about 0.03% of requests have a ridiculous response time, over 500000 ms ( yes, 500 thousand milliseconds !! ). Whatever the number of threads I use, from 5 to 50, the same behavior occurs sooner or later... for exaclty the same http requests. The application connects to a postgresql server, with the apache commons connection pool.
Could it be that postgres is accepting the connection although it's too busy to answer it ? FYI, postgres has 250 available connections, and uses 4 or 5 at the same time at peak traffic simulations.
My tomcat configuration is close to default, 500 threads available ... 2 Gb for the jvm ...
I am also wondering if connection timeout configurations could be a plausible issue, since connections to tomcat don't seem to die at all ?
Thanks for your assistance, very appreciated.
ps .. feel free to ask about other configuration parameters, I'll provide more info if needed.