The first real-life test
In order to be able to analyze the behaviour of the Sun T2000, we decided to launch it directly in the production environment. So we switched it online parallel to the Opteron machine, also in order to have a direct comparison.
Our test scenario:
Tier 1: 1 instance of Apache with mod_jk as loadbalancer (on the Sun E420R)
Tier 2: 1 instance of Tomcat (on the AMD Opteron machine) and
1 instance of Tomcat (on the Sun Fire T2000)
Tier 3: 1 instance of MySQL (on the Xeon machine)
The first impression:
During the test, the load average went up on all machines (Opteron machine from 1.4 to 12, Sun T2000 from 2.5 to over 20 and even the Sun E420R from 0.5 to about 5) compared to a situation with the same amount of requests! Something must be wrong... but what is it?
There are too many possible reasons: the mod_jk configuration, the Tomcat configuration, the MySQL configuration? We have to try!