Using iFiles in Irule for maintenance page and caching

Hello

I want to handle the maintenance page of a website on my F5. I read and implement it following the instruction in the article of Jason Rahm :

https://devcentral.f5.com/articles/v111-ndashexternal-file-access-from-irules-via-ifiles.U43lX1MYXjE

It's easy to configure and works perfect.

I wonder if each client request will make a disk access to deliver objects or if these objects are upload somewhere in memory. The fact is that i can't succeed to cache these objects in an web-acceleration profile and don't what disk access for each request.

Thanks for your answer.

Regards

Frédéric