Classic ASP site requests randomly hang in IIS7 - iis-7

I have a new IIS7 box running Windows Server 2008 Web Edition (x64), and I have set up an existing classic ASP site there. The site works fine and super speedy for the most part, but will randomly hang (about 1 out of 20 or so requests). By hanging, I mean I will click a page from the browser, and the browser (Crome on Mac) never responds -- it just continually loads until I finally get the following error after about 3 or so minutes:
Error 7 (net::ERR_TIMED_OUT): The operation timed out.
I'm pretty sure this is a Chrome-specific error, so I'm not too hung up on the actual error, but the cause of the time out. The site connects to a SQL 2005 server on the same network, but I'm pretty sure this isn't a SQL timeout, as that would happen within 30 seconds, and give me a specific error about SQL. I think this is an issue w/ my site, or the server.
Note that often after seeing this, I can simply stop the request and reload the page, and it will load just fine, super speedy again.
I'm not even sure where to begin troubleshooting this. I have to figure this out, otherwise this will mean a new server purchase down the drain.
Thanks in advance for any suggestions.

I've noticed a few more things about this problem. It'll happen more often after I've published files to the server (even static content like js or css files). It'll also happen occasionally on other sites running ASP.NET. Namely I've noticed the timeout on dotnetkicks.com which is also running IIS 7.5. Again, this only occurs in Chrome.
I've also tried uninstalling and re-installing Chrome but the problem continues. My next step is to try this from a couple different computers running Chrome outside my network.
UPDATE (April 29, 2011)
So I moved to Colorado a couple weeks ago and I haven't seen this problem occur even once since I moved. That leads me to conclude that 1.) my internet connection in Dallas was flaky and 2.) Chrome was less forgiving of a poor connection than other browsers. And of course, it basically rules out any possibility of there being a problem at the server's end.

Related

My Windows Azure site is all the sudden incredibly slow?

Basically I've been hosting a website on Windows Azure for a couple of months now.
Previously everything has been running smoothly. However all the sudden my site is loading INCREDIBLY slow (we're talking 20s load time). I have no idea what happend - I was running shared mode and before this point everything was running fine.
Below are my stats for the last 7 days (I don't know what else to upload):
I tried getting support but apparently my plan does not provide technical support.
I decided to upgrade to standard hosting but it's been 30 minutes now and my site is still running just as slow.
Also when I debug it locally everything runs just fine. Furthermore my I'm not connecting to any databases so what could the issue be????
Sometimes the site doesn't even load at all and displays errors such as:
500 - Internal server error
502 - Web server received an invalid response while acting as a gateway or proxy server.
What could be the problem - what am I supposed to do? Apparently Microsoft provide absolutely NO support so I guess I'm simply forced to switch to another hosting provider if I cannot figure out the issue myself?
have you found something that has increased load(on lines of user hits,transactions) on your sites? since you are running shared mode, you are sharing resources with multiple sites on the same server which could be the reason.
It might be an indication for you to go to dedicated mode.

Slow page refresh times during development

We have a reasonably large ASP.NET MVC app that I work on in Visual Studio 2012 on Win 8. I have a strange issue with slow page load times after recompilation. Usually, the actual build time is about 5 seconds, then the browser opens up and it takes 1-2 minutes to load the page.
Some points:
It loads slowly whether I change a view or recompile the project completely
This is not a performance issue, everything else works really well, there is enough RAM etc.
It happens only with IIS Express. When I switch to the default development server, it works fine.
All the other devs in my team use IIS Express, but they do not have this problem.
I tried to re-install IIS and to use v7.5 instead of v8 and recreated all config files. No luck.
I tried to disable all extensions, obviously it didn't affect load times too.
There is nothing abnormal in Task Manager
It's a virtual machine on my Macbook Pro, but again – this is not a performance problem.
What else can I try?
Solved by turning off Windows Defender Service. Everything is a hundred times faster now.
UPDATE: I failed to find a reason why Windows Defender is using lots of CPU power pretty much all the time. I tried to google it and it turns out that many people have a similar problem on Win 8 with no good solution.
If you really want to leave Defender on, you can add the project folder path as an exception, but it still will be slow-ish.
Hope it helps someone.
UPDATE 2: The above still holds true in Windows 10. Especially if you're running it in a virtual machine (I run it in Parallels on Mac). The overall speed increase, not only page refresh times, is very noticeable.
UPDATE 3: Apparently Windows Defender has a habit of silently turning itself back on again. So, be wary of that.
After viewing this question and answer above I found that Windows Defender Service was already turned off for me, however, I was running AVG. I disabled AVG and sure enough the lag went completely away!
So if Windows Defender Service is turned off for you and you are running some sort of system protection like AV try disabling that.

How can I trace an apparent memory leak in an asp.net application?

Some background info:
We have several websites running on a 64-bit machine with IIS6
These websites all have the same core code, but different skins and content
We have a SQL 2005 database which is fairly heavily used throughout the site
Historically we've used SQL stored procs, but have been gradually transitioning to NHibernate. The majority of our code uses NHibernate now, but not all.
These sites have been running fine on our live web server for a while, although we get a few errors a day regarding SQL connectivity / deadlocking.
Last Thursday we noticed the sites going very slow, then checking task manager revealed one of the websites was hogging over 1.6Gb of memory. Ever since then we've been restarting the app and watching it slowly increase in size over the course of the day.
We apparently have a memory leak (or at least, that's the effect), but I'm losing hair trying to work out how to trace it.
It only appears to be happening on this one website, even though as far as I am aware nothing had changed in the code before it started happenning. It is, however, our busiest website so it could be a traffic issue.
Debug Diagnostics hasn't revealed any issues.
Refreshing certain pages very quickly causes the memory to jump up rapidly, then fall slightly, but all the time the gradual progression is upwards.
I cannot replicate the issue on our test servers or locally. Probably because the traffic has something to do with it.
My suspicion is that the problem lies in database connectivity / locking. However, I'm not sure how that would cause the problem specified.
Any ideas?
Edit
Okay so not exactly sure I've found the problem but we're getting closer. It's definately SQL related. The error log reveals lots of errors since last thursday.
It all happened after we ran some windows updates on our servers. One of the updates failed on the SQL server so not sure if this caused some problems.
The warnings we're getting are:
SQL Server has encountered XX occurence(s) of I/O requests taking longer than 15 seconds to complete on file .. tempdb.mdf
Where XX is anything between 17 and 90! Does that sound like a deadlocking issue?
Followed by the following erors:
Unable to complete login process due to delay in opening server connection
These coincide with our log times for when the websites have been "blipping".
We've increased the page file size on SQL server to the recommended size, as it was set to a max of 4Gb, but recommended was 12Gb. I think we may need to roll back the windows updates we did on Thursday if that doesn't fix it.
Unfortunately I can't get into Activity monitor as it tells me Timeout expired!
Edit
Okay after a reboot I'm into Activity monitor. How many sleeping processes would you say would be normal? We have roughly 127 sleeping. That's serving over 10 websites.
If there is a deadlock or timeout issue, will NHibernate not clean up its connections properly?
Okay so in the end it seems it's quite complex. Sql deadlocks and data problems, heightened it seems by anti-virus software that was locking up or choking on a file.
Turning off the anti-virus reduced the problems, but we still need to resolve the underlying data issues.

IIS7 and IE6 ssl issues

I have a newly deployed mvc app on a win2008 server box.
I am trying to troubleshoot some very strange ie6 behaviour when over https. if a ie6 user connects to the webserver over https a simple post back or ajax call takes around 1 minute to complete, no errors are raised on the browser, it just sits there ticking away for about a minute, then completes as expected (both server and client as expected). the same post back or ajax call over http works in < 2 seconds.
There are no errors or events raised on the server, so i am flying blind here.
has anyone experienced this behaviour before, any ideas? with no errors or events to work with im not sure where to start. any other browser over https works fine, just ie6.
cheers
andrew
a quick follow up on this one. on further investigation the issue was only occurring on windows 2000 ie6 machines, xp and ie6 was ok. I guess from these results there must be something in the encryption/decryption framework on windows 2000 conflicting with the iis7 server.
I have managed to convince the windows 2000 ie6 users that its time to upgrade!
This brings up another question, when, if at all, do you think its acceptable to block certain versions of software from your web apps?
andrew

Internet Explorer hanging when debugging ASP.NET app

This problem is beginning to annoy.
After my machine (Vista Ultimate) has been up for a while, running my ASP.NET web site project for debugging in VS2008 results in Internet Explorer "hanging". It doesn't seem to get past the network access stage, you know when it says "Loading web site", or "Waiting for".
I've attached a screenshot of IE. Note the status bar. It stays like that forever. I have to restart it and cross my fingers for it to work the next time. Invariably, it doesn't.
This happened with IE7 and IE8.
I am using the ASP.NET Web Development Server/Cassini. I have tried restarting this each time which seemed ot have got it, but then not so any more.
I'm up to date on patches.
ie screenshot http://img40.imageshack.us/img40/5446/iehanging.png
So thankfully Microsoft have finally released Security Essentials.
This meant I could de-install AVG (Free and paid-for versions) from my machine.
Hey presto, it works!
I would check the following
1) that your not starting IE against the webserver againt the wrong port, if your using the development IIS then it changes ports at times. That combined with you setting up the browser to launch against a the old port could create this problem.
2) Stop the local IIS and restart it (Again make sure your pointing towards the correct port)
3) Make sure you dont have any hung IE in task manager ( this happens to me sometimes ). Basiclly you have a IE in task manager that uses less then 1mb of ram and does not show on the taskbar, if thats the case kill them.
This doesn't sound, strictly speaking, like a hang. Can that tab/other tabs be navigated to other sites? Is your machine configured to use a proxy?
Is the request actually sent? Using Fiddler2 from www.fiddler2.com with the URL http://ipv4.fiddler:56125/ will show you, and help determine where in IE the problem might be.
I just had a similar problem that took about a week to unravel. Using AVG 9 Business Edition.
I'm on a Windows 7 machine with Visual Studio 2010 SP1, debugging ASP.NET sites running in IIS, with the same "hang" behavior you're seeing. Disabling LinkScanner and Online Shield in AVG fixed the problem.

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