Hello,
I've been tasked (for my sins, which must have been huge!) with performance testing an application framework that sits on top of Tomcat and uses Axis as the soap server. My initial testing slams the server as hard as possible with 10 - 500 users stepping up 10 ever 60 seconds, each running an identical script in an endless loop. The purpose being to identify any points where synchronization was occurring. I'm seeing a response time that is almost linear with load (97% correlation) which implies, too me, a synchronization issue. I started to localize the problem by isolating components. Currently I have the soap method proxy turning the response around without calling the application framework, so the only components under test is Axis, ignoring the infrastructure which is a 4CPU 2Gb blade server running Tomcat & the 1.4.1 JVM on RedHat Advanced Server.
I'm still seeing the linear response time change with increasing load. Further investigation with JProbe (under XP) pointed the finger at javax.xml.parsers.DocumentBuilderFactory. A JVM level thread dump with 10 users hitting the server showed org.apache.xerces.DocumentBuilderFactoryImpl holding a lock and 3 other threads waiting on the lock.
That's the background, now the question.
Has anybody encountered a similar problem and could give me some pointers on possible configuration options or other any other suggestion that might help remove this bottleneck.
If there's a well documented solution to this then, firstly I'd love a pointer to it as a 30min search on Google failed to find anything that seemed relevant. Secondly I apologize for wasting people's time, web-services/soap is a new area for me & I'm under some time pressure on this task so it's quite possible I've missed the obvious.
Ray Sutton
Systems Engineer
The information in this electronic mail message is sender's business Confidential and may be legally privileged. It is intended solely for the addressee(s). Access to this Internet electronic mail message by anyone else is unauthorized. If you are not the intended recipient, any disclosure, copying, distribution or any action taken or omitted to be taken in reliance on it is prohibited and may be unlawful.
The sender believes that this E-mail and any attachments were free of any virus, worm, Trojan horse, and/or malicious code when sent. This message and its attachments could have been infected during transmission. By reading the message and opening any attachments, the recipient accepts full responsibility for taking protective and remedial action about viruses and other defects. Galileo International is not liable for any loss or damage arising in any way from this message or its attachments.
