Tomcat and AIX 5

[Quiks]

Hi,

I'm developping Web Applications in Java. I'm using Tomcat as a Web
Server. Everythings goes well under Linux and Windows. I have a B50
with AIX 5L and the latest Maintenance Package installed. I've also
installed AIX SDK 14. I've then installed Tomcat (4.1.24) from Jakarta
Project.

My problem is when I start using my Web App (which act like a server
for remote clients), the paging file size start to increase. Not
immediately, but after 3/4 hours, my paging file increases by 10 MB
every 30 minutes. I have 256Mb of RAM and I did configure two paging
files (their size is huge for testing purpose : 2.5 GB by file) In
fact, the clients who are contacting the server are producing an heavy
traffic on the server (for testing purpose). Even if I stop this
traffic, the paging file size does'nt decrease.
I've used 'svmon -P' to see which process is exactily causing these
troubles. Of course, I mentionned that it is Tomcat itself (the java
process which handles Tomcat). And when Tomcat increases, so did the
paging file. I read a lot about memory in IBM's website for AIX and,
as far as I know, system's algorithms should normally clean up paging
space after usage. If not, it should be because the program is not
releasing the memory (in our case, it's the JVM). So I ask me the
question if there are already had problems regarding AIX SDK14 and the
memory usage. If not, does someone have an issue to solve my problem ?

Thanks in advance,
quiks.

 

[chlawren]

Hi,

I am also seeing some performance issues when running tomcat.

When I first configured and installed tomcat I added an entry to the inittab and found multiple tomcat processes being spawned, this was due to the tomcat process stopping and being started somewhere in the application. I added nce: to the inittab and that resovled the multiple process issue.

I have continued investigation on why the process is being restarted then also noticed that my 18-way system is showing cpu utilization at around 95% for approx 3-5 secs at this happens every 10 minutes or so.

I have no idea at the moment about what is going on as I dont knwo much about tomcat however reading some performance docs you can run the following commands to investigate the number of threads being spawned from the java process id.


# ps -p <JAVAPID> -m -o THREAD

for cpu stats etc run

# tprof -skex sleep 60

you can investigate cpu utilization from the kernel and identify if there are any issues here.

Do you have any idea's or info on my issue?

Thanks

Chris.