What starts first Application_Start or WebRole's OnStart?

Question

I have MVC project on Windows Azure. This project has WebRole with method OnStart. And I want to know what starts first Application_Start of Global.asax or WebRole's OnStart?

score 5 · Accepted Answer · answered Jul 15 '11 at 15:24

Pretty sure this is non-deteministic after SDK 1.3. Trying to time something from one to the other will just end in a race condition.

Prior to 1.3, the Hosted Worker Core (HWC) was hosted in the RoleEntryPoint, so there was a deterministic startup (OnStart, Application_OnStart, IIRC). However, with IIS hosting the web now, it is the IISConfigurator.exe that creates the app pool, etc, and eventually w3wp.exe hosts your web site. This is a different process than your RoleEntryPoint, so either one could start first.

score 3 · Answer 2 · edited Jul 19 '12 at 23:32

3

I can't find any 100% complete references on this (about the best I've seen is http://blog.syntaxc4.net/?p=271), but I believe the sequence is:

Any startup tasks are run
WebRole OnStart method is called
The WebRole Run() method is called - and at the same time IIS starts the websites - so at this point Application_Start will get called for the first time.

edited Jul 19 '12 at 23:32

cory-fowler

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answered Jul 15 '11 at 09:42

Stuart

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score 0 · Answer 3 · answered Oct 30 '17 at 20:03

0

According to Microsoft's documentation, the Application_Start method is called after the OnStart method.

answered Oct 30 '17 at 20:03

Brendan L

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What starts first Application_Start or WebRole's OnStart?

3 Answers3

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