Yes, this is a limitation of the current XPages implementation which makes it difficult to use XPages as "XAgents" in order to produce content for a REST API with good response times or stream large attachments to a browser.

Only one XPage can produce content for a user session at the same time.

I wrote an article about this topic for our XPages2Eclipse product documentation:
http://xpages2eclipse.mindoo.de/web/x2ewiki.nsf/dx/JavaScriptServletMode

 

Our product does not have that limitation, it supports writing code in JavaScript and Java that is stored as standard SSJS libraries and can be called via a URL.

As an alternative, you could consider developing your own servlet in Java as an Eclipse plugin. Details can be found in the OpenNTF blog at:
http://www.openntf.org/blogs/openntf.nsf/d6plinks/NHEF-8JB9DN

Hi Karsten ,

 

Is there any configuration in domino server or in xpage app that can override this.

I am absolutely sure before i reconfigure my server, xpages was running concurently with no problems.


regards

Hi,

 

as far as I know there is no switch. I talked to Phil Riand, the XPages architect at IBM, about this topic a few weeks ago. It's a known limitation, which is not a big problem if you are only using XPages for web rendering and fast REST calls. This did not help for our use case, because we were working on a web ui with a lots of (Ext.js) controls that are fed by REST request data and they only loaded one by one in our application, which did not meet our requirements. That's why we added that feature to XPages2Eclipse.

According to Phil, there are some plans to improve this situation for 8.5.3, but probably only with a configuration flag that you can set to disable this HttpSession synchronization for the whole database, which should only be done when you are producing your own content with XPages and are not using those XPages for the web ui. Looks like the code that they added on top of JavaServer Faces is not Thread-safe. Which is a pity if all you are doing is to bypass the XPages code and write something manually to the output stream.

 

My tests were done with 8.5.2. Maybe it was different in 8.5.1.