Current request spikes every 7 minutes - asp.net-mvc

On our webhomes on a iis 7.5 webserver there is an increase in active request in a cycle of 7 minutes. 5 minutes everything is quite normal then comes an increase in active request for 2 minutes.
While active requests increases, ntoskrnl.exe also has an increase in cpu load.
Are there anybody who can give me any clues to what I shall look for?

One of the things that we did notice, was that the Garbage Collector was going nuts every 5 minuttes.
After a server restart everything is fine again.

Related

Randomly degrading heroku DB performance?

So I am working on a pretty high traffic rails/heroku/postgres app, the backend only, and after running for hours, days, or weeks at times the database will randomly start taking 120 seconds to perform queries that usually take 2-3 seconds, and it clears up as soon as the app is restarted and everyone is essentially "kicked off". What could cause a database to start taking a ridiculously long time to perform all queries? The database is not running out of memory, it is being vacuumed regularly, and it is not running out of connections. There are around 500 users at times, dynos are autoscaling, and the web server is passenger. However this is probably something with PG as it is happening at the query level.

New Relic's pings not improving cold start

There's a similar question about app harbor on StackOverflow, but the user didn't try to use new relic to overcome the problem.
I deployed my ASP.NET MVC project on App Harbor. It's very easy to configure and you can even set automatic deployments from Git. However, as my website is still mainly used only by me, I was getting very long cold starts (over 15 secs). To avoid it, I installed New Relic. The idea was to simultaneously to monitor the application but also to create periodic pings that, according to "a lot of people", would drastically reduce the loading time.
It's not working. I have New Relic correctly pinging my application every minute, but I still get very long cold starts. For instance, 5 min ago, I've got a cold start of 16 seconds. 1 minute after, I got the page loaded in less than a second.
I know I could have used Pingdom or StillAlive to achieve the same result:
How do I improve app performance on AppHarbor?
I wouldn't like to do it because I like New Relic and I don't want to have a lot of add-on's on app harbor as they will slow down my website. Do you have any idea what might be causing it?
I'm not familiar with AppHarbor's setup. But if it's using IIS, the pinging is just keeping the application pool from reaching the idle timeout. But there the default IIS setting for the application pool to be recycled every 29 hours no matter the number of requests. And it's normally in the best interest to let it recycle once in a while, so working around it may not be in your best interest.
Your best bet is to reduce the number of things happening on application start. Precompiling your views is a good place to start. And heck, Stack Exchange/Stack Overflow precompiles views to avoid the application start up cost.

Rails 4 on Heroku extremely slow with loading

I've got Heroku deployment with my Rails 4 app and it's proving to be extremely slow. I'm not sure if my location has a factor as I'm based in Australia
I've got NewRelic addon and below is the problem that I'm seeing.
Category Segment % Time Avg calls Avg Time (ms)
View layouts/users Template 98.4 1.0 16,800
Based on this breakdown, I see that layout users is the problem for the performance (which is nearly 16.8 seconds!).
Is there a good way to profile this to find out exactly what functions are causing this problem and what are the best way to fix those?
Also another important thing to note is that when I go to map report it shows End User of 19.5 seconds which takes up a lot of time.
When an app on Heroku has only one web dyno and that dyno doesn't receive any traffic in 1 hour, the dyno goes to sleep.
When someone accesses the app, the dyno manager will automatically wake up the web dyno to run the web process type. This causing delay for this first request.
Are you noticing similar behaviour?

Pointers to speed up web app startup time

My SaaS ASP.Net MVC web app startup time is about 20 to 30 seconds. The typical usage pattern is tied to business hours. So, when the first user in the morning browses to the home page, the page takes about 20 to 30 seconds to load. Thereafter, performance on subsequent page loads is not a problem.
It's running on cloud-hosted infrastructure...Win2008 R2, quad core Xeon with 6GB RAM.
Any pointers as to what I can do to improve this startup time?
The problem might be that your application is being shutdown during idle periods. Try setting up a service to periodically make a request to your application and keep it alive.

How to improve Website Waiting time?

While website loading speed testing I found that website is sometimes loading very quickly and some times it takes lot of time to start loading. When I checked it in detail, I found on some requests wait time was just in few hundred milliseconds, while on some other request which was slow it was actually taking 5 to 30 seconds in wait time.
What may be the cause of this kind of deviation from few milliseconds to 30 or more seconds. And how to improve it.
The site is build upon ASP.net MVC3 and Microsoft SQL Server database.
What patterns are there i.e. are the same URLs always slow, and other URLs always fast, or does it just appear to be random?
Look at what else is running on the server, is it a dedicated server or a VPS?
Look at the DB performance i.e. is it consistent, which are the queries that are taking the longest time, most CPU, most IO etc.
How busy is the site, do the slowdowns match when the app-pool is being recycled or started up?

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