I have an application running on Apache 2.2, tomcat 6 and it uses struts framework, hibernate framework. We use Mysql at back end. We also interact with third party servers to place some requests that are requested by the user. Due to confidentiality constrains I can not tell you exactly what we do but I can assure you that we have not customized any thing and we use the most general builds availaible for Apache, tomcat etc. We use Linux platform. Lots of visitors visit our site, where they first pay using payment gateways, and then buy a product. To buy the product we again have to hit a third party site. Its a simple e-commerce kind of setup. The problem is that some times the server hangs. As in it does not responds and when we click on a link that (I know) is served by the tomcat container, it does not get loaded. Here is what i need help for:
- Since my hosting is on a headless linux platform, please suggest me a good debugging tool.
- We have logging in place and we print stack trace of almost all exception(if they happen), we always monitor catalina.out, but when the server hangs, we dont see any activity on catalina.out. may be this can give some one a clue.
- We have show_sql disabled for hibernate, we tried to enable it but still that was not sufficient to figure out if the application stucks on a query. We also have slow_sql log enabled but that does not show any significant queries. How can we check if my application is stuck on a query?
- If my application is not stuck on a query, how can i know where it is stuck?
- How can I get java stack dump?
- What are possible ways to resolve such a problem.
ANy suggestions are welcome. I thank you all in advance for reading my question and for the time you will devote writing an answer.