I am using ASP .NET SignalR to create a realtime game in the browser. It seems to run fine, other than occasional stutters on the display output.
I first noticed this when I deployed my application to a virtual PC in the cloud. To rule out bandwidth issues, I then deployed it to another virtual PC running locally.
Even when running the application from a virtual PC locally, I still get the stutters.
This issue does not happen when I run the application on local host using IIS express.
This makes me think that the issue has something to do with IIS, since both the cloud virtual PC and local virtual have this in common and local host does not.
After Googling I found lots of people advising to check certain settings in IIS.
These websocket settings were listed as possible culprits:
I don’t see any issues there though.
Another suggestion was to check the queue length in the advanced settings of the App Pool. Currently it is 1000. I believe that this is enough, as according to Perfmon, the number of requests received peeks at about 100 per second and sent at 80.
Has anyone else got any ideas?
I am using SignalR for ASP .NET 2.4.1 and IIS 10
Thanks
Looks like I blamed IIS wrongly, after further investigation I found the issue is most likely due to high CPU usage.
I ran Perfmon, and looked at the '%Processor Time' counters, and noticed that the application is frequently at 100%.
Related
I deployed node js server to Azure WebApp, and it worked fine. But, I see that sometime the response time is very slow. Also, I see that somewhere above 500 request/second the server start to fail handling request, and I see it use only 15% CPU. Now, I checked and the server return 500 error because the pipe is busy (by the win32 error code). That's why I was wondering if there is something I can change in the IISNode config to improve the server request capacity.
I already enabled the AlwaysOn feature, and also I add a check in Pingdom to keep the site alive. Also, I already changed nodeProcessCountPerApplication to 0 so it use all the available process.
Thank you,
Omer
One thing you can do is enable Always On. Without it, when your site hasn't been visited for 20 minutes the site gets taken down. Then the next time someone makes a request to your site Azure Web Apps warms up (re-sets up) your site but this process takes a few seconds.
Note that Always On is only available for sites in Basic, Standard, or Premium SKUs
Also, check out this page for tips on debugging Node.js apps in Azure Web Apps: https://azure.microsoft.com/en-us/documentation/articles/web-sites-nodejs-debug/
I have a website (orders.cpidealers.com) running on an Azure Virtual Machine currently configured to Basic, A2 (2 cores, 3.5 GB memory) monitoring 3 endpoints.
Every morning since Tuesday, June 24,
The website has been unavailable (the browser just spins, I don't even get a 401 or any error)
I can't RDP into the virtual machine,
The endpoint status shows a warning triangle (although when I click on the link next to it some say Not Available while others give a time, I'm not sure I know how to translate the endpoint status box).
To resolve the problem, I login to Azure and restart the Virtual Machine. So far, everything seems to work fine for the remainder of the day until I arrive to work in the morning at 7:30 (Mountain Time).
Any suggestions on how to troubleshoot this?
Well, it seems to me like your app somehow manages to hang IIS by wasting resources. Cant tell you more without any data. You should enable some performance counters monitoring and see what is going on.
http://azure.microsoft.com/en-us/documentation/articles/cloud-services-dotnet-use-performance-counters/
http://www.codeproject.com/Articles/303686/Windows-Azure-Diagnostics-Performance-Counters-In
It looks like the system was hanging as Rouen mentioned. From that, we found this article which seems to have resolved the problem: IIS: Web Application hangs periodically needs system reboot
Here is everything my developer did:
I changed a few other things on the server. Set the sql server to never auto close, which should help the performance in the morning, set the gupdate to manual ( we did that together ) and then I found this article, which seems an exact case for our problem so I set the Credentials Manager to automatic and restarted.
IIS: Web Application hangs periodically needs system reboot
I have a Website hosted on Windows Azure. This website is a custom ASP.NET MVC 4 site hosted as a shared web site instance. Within the past couple of days, I've started to get large spikes in CPU Time. These spikes have been sustained and have caused my web site to get suspended. However, I'm not sure how to determine the cause of these spikes. Here is what I've done so far:
I attempted to look at the diagnostics via the Windows Azure FTP drop. I did not see anything there.
I reviewed my Google Analytics to see if there was anything out of the ordinary. The site had 20 visitors yesterday. So nothing crazy.
How can I identify the culprit of the the CPU spike? Once it spikes, it just sits there for hours. I'm not sure what would cause this.
Thank you
Have you tried running your site on your local box and simulating your visitor traffic, exercising all your website's features?
Testing locally is 1000's of times easier and more revealing than trying to debug a site that's running live.
If you still can't find anything wrong when running locally, consider using logging and tracing to strategic points in your site so that you can see how often, and how long it takes for your site to execute complex operations.
Very suddenly without any changes or recent access my Azure virtual server is no longer available for RDP or web...I have logged into the azure control panel and everything appears to running without issue but it is not working.
I have checked the end points and they are present for both RDP and Web, totally weird.
I have 2 virtual servers and the other one is working fine and responding.
Anyone ever experience this? Just when my client wants to view his website as well...
http://cn-web-02.cloudapp.net is the URL
TIA
As I just answered for this question, Virtual Machines are in Preview and not in Production yet. There are several reasons why your Virtual Machines became unavailable (see other answer). Given that this is the second reported incident here today, it's a good guess it's related to the underlying Host OS being updated, which would take your Virtual Machine offline for a short period of time.
I tried your URL and it's available again. Just remember about this being in Preview, especially since you mention having a client that wants to view his website. If you put a production website in Virtual Machines, then you'll have to absorb the risk of not having an SLA.
Having said that: You can mitigate downtime risk by running two Virtual Machines, listening on a load-balanced input endpoint. Be sure to have both Virtual Machines in the same Availability Set. Doing that ensures that the Windows Azure fabric controller will not take both Virtual Machines offline at the same time when doing things like Host OS updates. If this were in Production, you'd then have a very high availability scenario. Even in Preview, you'll improve availability by taking advantage of Availability Sets. Note: You'll need to use some type of shared session cache, since visitors will now be sent to either one of your Virtual Machines.
I had same experience on it! We had 2 instances and all of its were re-imaged without any notified. I known it since we made some local change via RDP.
Reboot or Reimage may help! You may try!
Turns out it was an outage from Microsoft...for over 22 hours but everything is back up and running. This is the 2nd time in 6 months this has happened for long stretches...makes me a little nervous to say the least.
Thanks for the input everyone and for anyone that's interested MS have a good site that tracks the service levels on Azure. Windows Azure Service Dashboard
S
This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
App pool timeout for azure web sites
I am working on an asp.net mvc 4 app that is hosted in Windows Azure. This app will not have a lot of traffic as people will intermittently (once an hour) use it. I wanted to try using Windows Azure.
My app is currently set to use the FREE web site mode. I noticed that after 30 minutes, the site takes a long-time (> 5 seconds) to load. After that initial load, its fast. Then, if someone doesn't use it for another 30 minutes, it takes >5 seconds to load again.
I then tried upping the web site mode to a SHARED instance. I experienced the same problem there.
I then tried upping the web site mode to a RESERVED instance. The problem then goes away.
While I'd like to use Windows Azure, paying $50+ a month for a RESERVED instance is pretty expensive for a site that few have used up to this point. However, I can't have the initial lag. That will just defer the few users I have. You could say you get what you pay for. At the same time, I have a hard time believing others are experiencing this problem and not complaining. There has to be something I'm missing.
I figure the problem has to deal with the application pool resetting. However, I can't seem to figure a way around this. Is anyone familiar with this issue? Is there a way to fix it on a FREE or SHARED instance?
Thank you!
This is expected behavior based on how Windows Azure Web Sites work. The app pool they live in is spun up "on demand" and then hangs around for a time period.
For a detailed (and shameless plug) you can check out my article on this: http://www.simple-talk.com/dotnet/.net-framework/windows-azure-websites-%e2%80%93-a-new-hosting-model-for-windows-azure/
In summary:
Web Sites are hosted in a process on a farm of machines running IIS. If a site is idle for some time then the process is torn down automatically. Also, if the box is seeing a lot of pressure due to the other sites on the box the idle timeout may come down quite a bit (even as low as five minutes). When the next call comes in you'll see the process spun up again (likely on a completely different server). This is because you are in a shared environment (and is similar to how Heroku works). Once you move to reserved then you are the ONLY person on that virtual machine and if you suffer from noisy neighbor issues in processing its' because of your own stuff.
There are ways to keep your site "up", such as having a job that pings the url frequently; however, given that the idle timeout is somewhat fluid it may not solve every case. You can check out a recent post by Sandrino on how to use Azure Mobile Services as a job scheduler: http://fabriccontroller.net/blog/posts/job-scheduling-in-windows-azure/ . There are also 3rd party services available that can do the ping for you automatically.
To be honest, the web sites are a great feature for quick development and test, or even relatively low traffic sites as you are talking about. If you need a high level of uptime and better performance then you'll want to look at Reserved, or another option if the cost isn't in line with expectations.
This isn't an Azure problem. It is a "feature" of any web site hosted in IIS. The default time-out for app pools is 20 minutes. Read about App Pool timeouts here - http://technet.microsoft.com/en-us/library/cc771956(v=ws.10).aspx - one method is to create a keep alive page and ping the page every 10 minutes or so.