Slow performance on AIX

[oravecz]

Running IBM JDK 1.3.1 on AIX/RS6000 box.
jBoss 2.4.6 with Tomcat 4.0.3

Our app is performing about 10x slower than on a P3 700mhz NT box!? Doesn't appear to be specific to database activity, or web page serving. It seems that the overall VM speed is just very slow.

Wondering what performance tweaks may be available. We have already made sure the JIT (jitc) was running, as well as boosting the stack and heap space. Any other suggestions?

[respinola]

I am running JBoss on a IBM Regatta AIX and I am also seeing a dramatic decrease in speed. When performing a simple Bubblesort of 100,000 real numbers, my local machine is done in about 5 minutes. On the IBM Regatta AIX, it takes a little under 30 minutes to finish. Any ideas on what may be causing this?

[oravecz]

Our slow problems were related to the use of very _descriptive_ log4j output. AIX has a very slow implementation of determining the call stack, and thus takes about 100ms for each log statement to output. Note, this is only noticeable when you are logging those fields that require a stack trace to be generated.