Operating a Java Server on  a VPS requires some tweaking. First of all
you should check the current memory consumption in your scenario using,
for example, jconsole (which is part of the JDK since 1.5). In order to
connect to a running jconsole instance, you should some JMX system
properties, e.g.

-Dcom.sun.management.config.file=management.properties

and put a management.properties file in your ofbiz folder (next to
startofbiz.sh) that looks like this:

com.sun.management.jmxremote=true
com.sun.management.jmxremote.port=7777
com.sun.management.jmxremote.ssl=false
com.sun.management.jmxremote.authenticate=false

(assuming you are using the SUN JDKs). 

Note: this should never be used in production as the JMX access is
completely unsecured this way!

With the config above, you can connect via 

jconsole localhost:7777

Now run your load test or simulate your scenario and check the memory
data in jconsole. Trigger a few GC's.

Check the various memory regions by going to the "Memory" tab or
directly to MBeans --> java.lang --> MemoryPool.

In my experience in particular the CodeCache pool is very much oversized
and the SUN JVM allocates rather large chunks of memory here. Which is
normally not a problem, but VPS's tend to have very tight virtual memory
quotas (which seems really unnecessary). 

Anyway, in order to redruce memory consumption, you should limit heap,
perm space, code cache, using the VM settings

-Xms<heap>M -Xmx<heap>M -XX:ReservedCodeCacheSize=<cc>m
-XX:MaxPermSize=<perm>m

where <heap>,<cc>,<perm> are placeholders for your settings. 

While <perm> and <cc> should not change dramatically after your scenario
has run (so add a little on top of your measurements), the heap size
will also have
to reflect user session memory (so add some more. No idea how big a
session in ofbiz gets in the end).

Good luck,
Henning



Am Samstag, den 25.07.2009, 14:51 +0530 schrieb S K Pradeep Kumar:

> Hi All,
> 
>     We have deployed the ofbiz with tomcat on VPS server.
>    It is creating too many dummy sessions and consuming loot of memory.
>    Could you please help in this.
>     What might be the reason?
>     How can we customize the application to reduce memory consumption?
> 

Reply via email to