Hi, On 09.09.2009 06:56, balakarthik.baska...@wipro.com wrote: > Hi, > In our production envt,we are making use of a configuration of > Apache(2.2.10-1)+Mod_jk(1.2.27)+JBOSS(4.0.5)+ATG 2007.1. > > We are facing a problem where multiple content is being displayed to the > customer.It was observed that the pages were being periodically rendered > or rendered multiple times.The page was rendered with a standard > navigational header showing two times. Depending on the browser, the > duplicate headers was stacked vertically or horizontally. The issue was > further exasperated because a particular fragment was cached at Akamai, > and once this double header was served up by origin, it was then cached > at Akamai and included in customer pages at a very high rate. > > Our Analysis So far > > We did a local setup of the above configuration and we are able to > recreate the multiple content problem.The setup involves apache > configured with mod_jk having two worker nodes balanced by a load > balancer worker.The problem occurs when the app code takes a longer time > than the time defined in the socket_timeout parameter of the worker > nodes. We have set the socket_timeout config of the worker nodes to be 2 > secs for both nodes and the appserver jsp logic is made to sleep for > 3secs. > > The behaviour observed is as follows: > > The first worker node fails after the socket timeout time and the second > worker node is able to retreive the response from the app server.However > while turning on the debug of mod_jk,we are observing that a partial > content has been served by the AJP Connector/Container from the App > server for the node 1.Also,a full content has been served for the > request initiated by node2.The full content follows the partial content > that has been already sent to the client .Hence the browser has a > duplicate/multiple content shown to the customers. > > What are we looking for? > > The open question at this point that we have is how/what configuration > could either limit this partial response (or) send an error response to > the client when the worker node is found to be inactive? (or) handling > the situation of the app server taking a longer time to respond than the > defined timeouts (in mod_jk) and a partial content being writtent into > the socket,received by mod_jk and sent to the client? > > The problem gets aggravated when we akamai comes into picture.
Thanks a lot for your very careful analysis. I usually do not recommend socket_timeout, so that's why I never noticed such behaviour. But of course this is a bug which has to be fixed. Is there a possibility of getting a hand on the part of the debug log, where the problem occurs? I'm pretty sure, we can quickly fix it then. If the problem is easy for you to reproduce, would you mind testing once again using version 1.2.28 of mod_jk? There have been some changes there not directly related to the problem, but it would be good to know, whether you can still reproduce with 1.2.28. I will nevertheless investiaget, what's wrong in 1.2.27 and possibly also 1.2.28. Thanks again and a debug log snippet would be very helpful. Regards, Rainer --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
