Considerations for configuring application pools in SharePoint

I usually recommend my customers group similar web applications into the same application pool.  Each application pool brings additional server resources like memory.  In addition, the supported boundary for Application Pools is 10. 

Let’s say we have the following web applications.

https://collab

https://intranet

https://extranet

https://paycheck

I would consider the following configuration:

App Pool Name:	SharePoint Shared App Pool
Service Account:	Svc.SPShared
Apps:	https://collab https://intranet

 

App Pool Name:	SharePoint Extranet App Pool
Service Account:	Svc.SPExtranet
Apps:	https://extranet

 

App Pool Name:	SharePoint Paycheck
Service Account:	Svc.SPPaycheck
Apps:	https://paycheck

 

If you can group certain applications you should. However, in the case of payroll if someone managed to run some code as or compromise the SPShared account, they would not automatically have permissions to https://paycheck or https://extranet.

However, since https://collab and https://intranet both have lower impact in this scenario it might make sense for those web applications to share an application pool.

Obviously you would want to take performance into account and the actual content.  However, I would try to share application pools where it makes sense.