Launch worker process (w3wp.exe) automatically as soon as application pool starts
You can set up an application pool to start automatically but the worker process (w3wp.exe) will actually be launched once a request is made to the web site. However, in some scenarios you may want to have a worker process started automatically whenever an application pool starts. This is useful especially if a worker process launches slow for some reason.
To do that you can set startMode attribute of an application pool to AlwaysRunning in your applicationHost.config. For example:
<applicationPools> <add name="Default App Pool" startMode="AlwaysRunning" /> </applicationPools>
IIS 7.5 or newer.