I am having an issue where partial post-backs in ASP.NET cease to work when the IIS AppDomain recycles.
The scenario is this. I have a dashboard type web app that checks for updates at a timed interval through partial ajax post-backs. When I release updates to the web server and the AppDomain recycles the post-backs stop working unless the user refreshes the page. Since this is an app that stays up all day and is being monitored for changes without user input it can be a problem if suddenly it just stops updating.
How do I prevent the partial post-backs from stopping to work without a full page refresh post Session loss? And if that's not possible, how do I detect that the session has been lost from javascript so I can force a full page refresh?
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We have a WEBAPI service running on a windows asp.net MVC solution. There is a load method that takes about 40 minutes to complete and return status on the called page. During that time the browser window is tied up. What design options do we have if we want the web page to come back with submitted and the process to continue to run and complete. I don't care if page never shows complete, we can pull that from another status page.
I've done something similar in the past, even though in my case the delay was shorter - 40-50 seconds of loading of fresh data from multiple backend servers in a VPN. It was also in ASP.NET back then, but I believe that the approach is still feasible and you can get some ideas if I share my experience. I remember an old thread that I had favourited in the past and used the insight from it. You can check it out.
Here are some tips, but in short, because I don't remember the details anymore (excuse my google-assisted memory!):
You should start the task in a new thread and not wait for it in your main thread.
You should also make sure that the task is started only once and cannot be initiated infinite number of times by the user via refresh or via the UI. So, you better persist the state in the database, so at refresh, the new thread is created only if the database says that it has not been executed recently or it is not in progress.
Your page will be loaded and show its contents and you can display a .gif representing a progress bar, a loading wheel or something similar to the user.
The task you started will continue on the server. When it completes you can push and update the UI via ajax from within the code-behind to make the experience even smoother if you like.
On subsequent requests, you can just retrieve the state of your task from the database in order to display something like update completed at hh:mm:ss.
Hope this helps you and I wish you the best of luck!
I'm using the framework Meteor (Node.js).
I get this error message in my web browser when my project page is loaded:
The connection to ws://localhost:3000/sockjs/622/u2zaukpp/websocket was interrupted while the page was loading.
Why is it occuring?
It happens every single time you reload the page or it gets reloaded by the server.
Basically the page is constantly receiving data from the server (collections data, methods, or simply a ping). Since it is constantly open and Meteor forces a reload on code change (or you did force one by reloading the page), your browser freaks out and shows you this error.
It can also happen if the Meteor process is killed.
Thus, expect to see this error a lot during development, you don't have to worry about it.
I have a problem with xPages after rebuild, if a user tries to access a page after a rebuild the webpage starts to make continues requests to server, The application uses extlib and the dyamic content control.
The big problem here is that if you are making interval ajax request in the webpage, the same problem will happend without user actions. So all users having the webpage open after a new design is added will automatically get this problem which could probably kill the server.
I am not sure, but I think this might be a Extension Library problem
There is a youtube video of the problem here:
http://www.youtube.com/watch?v=y15XLtWsq80&feature=youtu.be
I have my site hosted on IIS hosting. Site has feature that needs calling WCF service and then return result. The issue is that site is processing calling to WCF service another web site calling is freezing and not return content fast (this is just static content). I setup two chrome instances with different imacros' scripts, which one is calling page that requests wcf service and another one page is just static content. So here I can just see that when first page that requests wcf services freezes, another one page also freezes and when first is released the second is too.
Do I need reconfigure something in my Web.Config or do should I do something else to get possible to get static content immediately.
I think that there are two seperate problems here:
Why does the page that uses the WCF service freeze
Why does the static content page freeze
On the page that calls the WCF service a common problem is that the WCF client is not closed. By default there are 10 WCF connections with a timeout of 1 min. The first 10 calls go fine (say they execute i 2 secs), then the 11th call comes, there are no free wcf connections it must therefore wait 58 secs for a connection to timeout and become available.
On why your static page freezes. It could be that your client only allows one connection to the site, the request for the static page is not sent untill the request for the page with the wcf services is complete.
You should check the IIS logs to see how must time IIS is reporting that the request is taking.
I would say that this is a threading issue. This MSDN KB article has some suggestions on how to tune your ASP.NET threading behavior:
http://support.microsoft.com/kb/821268
From article - ...you can tune the following parameters in your Machine.config file to best fit your situation:
maxWorkerThreads
minWorkerThreads
maxIoThreads
minFreeThreads
minLocalRequestFreeThreads
maxconnection
executionTimeout
To successfully resolve these problems, do the following:
Limit the number of ASP.NET requests that can execute at the same time to approximately 12 per CPU.
Permit Web service callbacks to freely use threads in the ThreadPool.
Select an appropriate value for the maxconnections parameter. Base your selection on the number of IP addresses and AppDomains that are used.
etc...
Consider such scenario: when you make a request to IIS your app changes, deletes or creates some file outside of App_Data folder. This often tends to be a log file which is mistakenly was put at bin folder of the app. The file system changes lead to AppDomain reloading by IIS as it thinks that app was changed, hence the experienced delay. This may or may not apply to your issue, but it is a common mistake in ASP.NET apps.
Well, maybe there is no problem...
It may be just the browser's same domain simultaneous requests limit.
Until the browser not finished the request to the first page (the WCF page), it won't send the request to the second page (the static).
Try this:
Use different browsers for each page (for example chrome/firefox).
Or open the second page in chrome in incognito window (Ctrl + Shift + N).
Or try to access each page from different computer.
You could try to use AppFabric and see what is wrong with your WCF services http://msdn.microsoft.com/en-us/windowsserver/ee695849
I have an online ClickOnce application that launches from a web page. After the application is closed, I would like the user to return to that page with some results passed from the application. Is this possible?
Right now the only solution I have is for the application to upload the results to my server, and have javascript on the launching webpage to poll the server every 15 seconds as it waits for results.
No. It is not possible to pass information directly back to the client browser from the ClickOnce installed application.
Your intuition is correct that you should have your application upload results to the server (presumably with the help of WCF) for subsequent processing and display via your polling page.
I'll also add, that in terms of your web application linking to data from the ClickOnce application you will need to come up with a common token between the web application and the ClickOnce application. Perhaps via a customised activation URL link that uses a common GUID generated for the client (e.g. http://myserver.com/myapplication.application?id=18c40c3d-183c-4c22-8127-37cac3be6492).